rot.js

/*
	This is rot.js, the ROguelike Toolkit in JavaScript.
	Version 0.5~dev, generated on Sat Apr 26 10:24:50 PDT 2014.
*/
/**
 * @namespace Top-level ROT namespace
 */
var ROT = {
	/**
	 * @returns {bool} Is rot.js supported by this browser?
	 */
	isSupported: function() {
		return !!(document.createElement("canvas").getContext && Function.prototype.bind);
	},

	/** Default with for display and map generators */
	DEFAULT_WIDTH: 80,
	/** Default height for display and map generators */
	DEFAULT_HEIGHT: 25,

	/** Directional constants. Ordering is important! */
	DIRS: {
		"4": [
			[ 0, -1],
			[ 1,  0],
			[ 0,  1],
			[-1,  0]
		],
		"8": [
			[ 0, -1],
			[ 1, -1],
			[ 1,  0],
			[ 1,  1],
			[ 0,  1],
			[-1,  1],
			[-1,  0],
			[-1, -1]
		],
		"6": [
			[-1, -1],
			[ 1, -1],
			[ 2,  0],
			[ 1,  1],
			[-1,  1],
			[-2,  0]
		]
	},

	/** Cancel key. */
	VK_CANCEL: 3, 
	/** Help key. */
	VK_HELP: 6, 
	/** Backspace key. */
	VK_BACK_SPACE: 8, 
	/** Tab key. */
	VK_TAB: 9, 
	/** 5 key on Numpad when NumLock is unlocked. Or on Mac, clear key which is positioned at NumLock key. */
	VK_CLEAR: 12, 
	/** Return/enter key on the main keyboard. */
	VK_RETURN: 13, 
	/** Reserved, but not used. */
	VK_ENTER: 14, 
	/** Shift key. */
	VK_SHIFT: 16, 
	/** Control key. */
	VK_CONTROL: 17, 
	/** Alt (Option on Mac) key. */
	VK_ALT: 18, 
	/** Pause key. */
	VK_PAUSE: 19, 
	/** Caps lock. */
	VK_CAPS_LOCK: 20, 
	/** Escape key. */
	VK_ESCAPE: 27, 
	/** Space bar. */
	VK_SPACE: 32, 
	/** Page Up key. */
	VK_PAGE_UP: 33, 
	/** Page Down key. */
	VK_PAGE_DOWN: 34, 
	/** End key. */
	VK_END: 35, 
	/** Home key. */
	VK_HOME: 36, 
	/** Left arrow. */
	VK_LEFT: 37, 
	/** Up arrow. */
	VK_UP: 38, 
	/** Right arrow. */
	VK_RIGHT: 39, 
	/** Down arrow. */
	VK_DOWN: 40, 
	/** Print Screen key. */
	VK_PRINTSCREEN: 44, 
	/** Ins(ert) key. */
	VK_INSERT: 45, 
	/** Del(ete) key. */
	VK_DELETE: 46, 
	/***/
	VK_0: 48,
	/***/
	VK_1: 49,
	/***/
	VK_2: 50,
	/***/
	VK_3: 51,
	/***/
	VK_4: 52,
	/***/
	VK_5: 53,
	/***/
	VK_6: 54,
	/***/
	VK_7: 55,
	/***/
	VK_8: 56,
	/***/
	VK_9: 57,
	/** Colon (:) key. Requires Gecko 15.0 */
	VK_COLON: 58, 
	/** Semicolon (;) key. */
	VK_SEMICOLON: 59, 
	/** Less-than (<) key. Requires Gecko 15.0 */
	VK_LESS_THAN: 60, 
	/** Equals (=) key. */
	VK_EQUALS: 61, 
	/** Greater-than (>) key. Requires Gecko 15.0 */
	VK_GREATER_THAN: 62, 
	/** Question mark (?) key. Requires Gecko 15.0 */
	VK_QUESTION_MARK: 63, 
	/** Atmark (@) key. Requires Gecko 15.0 */
	VK_AT: 64, 
	/***/
	VK_A: 65,
	/***/
	VK_B: 66,
	/***/
	VK_C: 67,
	/***/
	VK_D: 68,
	/***/
	VK_E: 69,
	/***/
	VK_F: 70,
	/***/
	VK_G: 71,
	/***/
	VK_H: 72,
	/***/
	VK_I: 73,
	/***/
	VK_J: 74,
	/***/
	VK_K: 75,
	/***/
	VK_L: 76,
	/***/
	VK_M: 77,
	/***/
	VK_N: 78,
	/***/
	VK_O: 79,
	/***/
	VK_P: 80,
	/***/
	VK_Q: 81,
	/***/
	VK_R: 82,
	/***/
	VK_S: 83,
	/***/
	VK_T: 84,
	/***/
	VK_U: 85,
	/***/
	VK_V: 86,
	/***/
	VK_W: 87,
	/***/
	VK_X: 88,
	/***/
	VK_Y: 89,
	/***/
	VK_Z: 90,
	/***/
	VK_CONTEXT_MENU: 93,
	/** 0 on the numeric keypad. */
	VK_NUMPAD0: 96, 
	/** 1 on the numeric keypad. */
	VK_NUMPAD1: 97, 
	/** 2 on the numeric keypad. */
	VK_NUMPAD2: 98, 
	/** 3 on the numeric keypad. */
	VK_NUMPAD3: 99, 
	/** 4 on the numeric keypad. */
	VK_NUMPAD4: 100, 
	/** 5 on the numeric keypad. */
	VK_NUMPAD5: 101, 
	/** 6 on the numeric keypad. */
	VK_NUMPAD6: 102, 
	/** 7 on the numeric keypad. */
	VK_NUMPAD7: 103, 
	/** 8 on the numeric keypad. */
	VK_NUMPAD8: 104, 
	/** 9 on the numeric keypad. */
	VK_NUMPAD9: 105, 
	/** * on the numeric keypad. */
	VK_MULTIPLY: 106,
	/** + on the numeric keypad. */
	VK_ADD: 107, 
	/***/
	VK_SEPARATOR: 108,
	/** - on the numeric keypad. */
	VK_SUBTRACT: 109, 
	/** Decimal point on the numeric keypad. */
	VK_DECIMAL: 110, 
	/** / on the numeric keypad. */
	VK_DIVIDE: 111, 
	/** F1 key. */
	VK_F1: 112, 
	/** F2 key. */
	VK_F2: 113, 
	/** F3 key. */
	VK_F3: 114, 
	/** F4 key. */
	VK_F4: 115, 
	/** F5 key. */
	VK_F5: 116, 
	/** F6 key. */
	VK_F6: 117, 
	/** F7 key. */
	VK_F7: 118, 
	/** F8 key. */
	VK_F8: 119, 
	/** F9 key. */
	VK_F9: 120, 
	/** F10 key. */
	VK_F10: 121, 
	/** F11 key. */
	VK_F11: 122, 
	/** F12 key. */
	VK_F12: 123, 
	/** F13 key. */
	VK_F13: 124, 
	/** F14 key. */
	VK_F14: 125, 
	/** F15 key. */
	VK_F15: 126, 
	/** F16 key. */
	VK_F16: 127, 
	/** F17 key. */
	VK_F17: 128, 
	/** F18 key. */
	VK_F18: 129, 
	/** F19 key. */
	VK_F19: 130, 
	/** F20 key. */
	VK_F20: 131, 
	/** F21 key. */
	VK_F21: 132, 
	/** F22 key. */
	VK_F22: 133, 
	/** F23 key. */
	VK_F23: 134, 
	/** F24 key. */
	VK_F24: 135, 
	/** Num Lock key. */
	VK_NUM_LOCK: 144, 
	/** Scroll Lock key. */
	VK_SCROLL_LOCK: 145, 
	/** Circumflex (^) key. Requires Gecko 15.0 */
	VK_CIRCUMFLEX: 160, 
	/** Exclamation (!) key. Requires Gecko 15.0 */
	VK_EXCLAMATION: 161, 
	/** Double quote () key. Requires Gecko 15.0 */
	VK_DOUBLE_QUOTE: 162, 
	/** Hash (#) key. Requires Gecko 15.0 */
	VK_HASH: 163, 
	/** Dollar sign ($) key. Requires Gecko 15.0 */
	VK_DOLLAR: 164, 
	/** Percent (%) key. Requires Gecko 15.0 */
	VK_PERCENT: 165, 
	/** Ampersand (&) key. Requires Gecko 15.0 */
	VK_AMPERSAND: 166, 
	/** Underscore (_) key. Requires Gecko 15.0 */
	VK_UNDERSCORE: 167, 
	/** Open parenthesis (() key. Requires Gecko 15.0 */
	VK_OPEN_PAREN: 168, 
	/** Close parenthesis ()) key. Requires Gecko 15.0 */
	VK_CLOSE_PAREN: 169, 
	/* Asterisk (*) key. Requires Gecko 15.0 */
	VK_ASTERISK: 170,
	/** Plus (+) key. Requires Gecko 15.0 */
	VK_PLUS: 171, 
	/** Pipe (|) key. Requires Gecko 15.0 */
	VK_PIPE: 172, 
	/** Hyphen-US/docs/Minus (-) key. Requires Gecko 15.0 */
	VK_HYPHEN_MINUS: 173, 
	/** Open curly bracket ({) key. Requires Gecko 15.0 */
	VK_OPEN_CURLY_BRACKET: 174, 
	/** Close curly bracket (}) key. Requires Gecko 15.0 */
	VK_CLOSE_CURLY_BRACKET: 175, 
	/** Tilde (~) key. Requires Gecko 15.0 */
	VK_TILDE: 176, 
	/** Comma (,) key. */
	VK_COMMA: 188, 
	/** Period (.) key. */
	VK_PERIOD: 190, 
	/** Slash (/) key. */
	VK_SLASH: 191, 
	/** Back tick (`) key. */
	VK_BACK_QUOTE: 192, 
	/** Open square bracket ([) key. */
	VK_OPEN_BRACKET: 219, 
	/** Back slash (\) key. */
	VK_BACK_SLASH: 220, 
	/** Close square bracket (]) key. */
	VK_CLOSE_BRACKET: 221, 
	/** Quote (''') key. */
	VK_QUOTE: 222, 
	/** Meta key on Linux, Command key on Mac. */
	VK_META: 224, 
	/** AltGr key on Linux. Requires Gecko 15.0 */
	VK_ALTGR: 225, 
	/** Windows logo key on Windows. Or Super or Hyper key on Linux. Requires Gecko 15.0 */
	VK_WIN: 91, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_KANA: 21, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_HANGUL: 21, 
	/** 英数 key on Japanese Mac keyboard. Requires Gecko 15.0 */
	VK_EISU: 22, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_JUNJA: 23, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_FINAL: 24, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_HANJA: 25, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_KANJI: 25, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_CONVERT: 28, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_NONCONVERT: 29, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_ACCEPT: 30, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_MODECHANGE: 31, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_SELECT: 41, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_PRINT: 42, 
	/** Linux support for this keycode was added in Gecko 4.0. */
	VK_EXECUTE: 43, 
	/** Linux support for this keycode was added in Gecko 4.0.	 */
	VK_SLEEP: 95 
};
/**
 * @namespace
 * Contains text tokenization and breaking routines
 */
ROT.Text = {
	RE_COLORS: /%([bc]){([^}]*)}/g,

	/* token types */
	TYPE_TEXT:		0,
	TYPE_NEWLINE:	1,
	TYPE_FG:		2,
	TYPE_BG:		3,

	/**
	 * Measure size of a resulting text block
	 */
	measure: function(str, maxWidth) {
		var result = {width:0, height:1};
		var tokens = this.tokenize(str, maxWidth);
		var lineWidth = 0;

		for (var i=0;i<tokens.length;i++) {
			var token = tokens[i];
			switch (token.type) {
				case this.TYPE_TEXT:
					lineWidth += token.value.length;
				break;

				case this.TYPE_NEWLINE:
					result.height++;
					result.width = Math.max(result.width, lineWidth);
					lineWidth = 0;
				break;
			}
		}
		result.width = Math.max(result.width, lineWidth);

		return result;
	},

	/**
	 * Convert string to a series of a formatting commands
	 */
	tokenize: function(str, maxWidth) {
		var result = [];

		/* first tokenization pass - split texts and color formatting commands */
		var offset = 0;
		str.replace(this.RE_COLORS, function(match, type, name, index) {
			/* string before */
			var part = str.substring(offset, index);
			if (part.length) {
				result.push({
					type: ROT.Text.TYPE_TEXT,
					value: part
				});
			}

			/* color command */
			result.push({
				type: (type == "c" ? ROT.Text.TYPE_FG : ROT.Text.TYPE_BG),
				value: name.trim()
			});

			offset = index + match.length;
			return "";
		});

		/* last remaining part */
		var part = str.substring(offset);
		if (part.length) {
			result.push({
				type: ROT.Text.TYPE_TEXT,
				value: part
			});
		}

		return this._breakLines(result, maxWidth);
	},

	/* insert line breaks into first-pass tokenized data */
	_breakLines: function(tokens, maxWidth) {
		if (!maxWidth) { maxWidth = Infinity; };

		var i = 0;
		var lineLength = 0;
		var lastTokenWithSpace = -1;

		while (i < tokens.length) { /* take all text tokens, remove space, apply linebreaks */
			var token = tokens[i];
			if (token.type == ROT.Text.TYPE_NEWLINE) { /* reset */
				lineLength = 0; 
				lastTokenWithSpace = -1;
			}
			if (token.type != ROT.Text.TYPE_TEXT) { /* skip non-text tokens */
				i++;
				continue; 
			}

			/* remove spaces at the beginning of line */
			while (lineLength == 0 && token.value.charAt(0) == " ") { token.value = token.value.substring(1); }

			/* forced newline? insert two new tokens after this one */
			var index = token.value.indexOf("\n");
			if (index != -1) { 
				token.value = this._breakInsideToken(tokens, i, index, true); 

				/* if there are spaces at the end, we must remove them (we do not want the line too long) */
				var arr = token.value.split("");
				while (arr[arr.length-1] == " ") { arr.pop(); }
				token.value = arr.join("");
			}

			/* token degenerated? */
			if (!token.value.length) {
				tokens.splice(i, 1);
				continue;
			}

			if (lineLength + token.value.length > maxWidth) { /* line too long, find a suitable breaking spot */

				/* is it possible to break within this token? */
				var index = -1;
				while (1) {
					var nextIndex = token.value.indexOf(" ", index+1);
					if (nextIndex == -1) { break; }
					if (lineLength + nextIndex > maxWidth) { break; }
					index = nextIndex;
				}

				if (index != -1) { /* break at space within this one */
					token.value = this._breakInsideToken(tokens, i, index, true);
				} else if (lastTokenWithSpace != -1) { /* is there a previous token where a break can occur? */
					var token = tokens[lastTokenWithSpace];
					var breakIndex = token.value.lastIndexOf(" ");
					token.value = this._breakInsideToken(tokens, lastTokenWithSpace, breakIndex, true);
					i = lastTokenWithSpace;
				} else { /* force break in this token */
					token.value = this._breakInsideToken(tokens, i, maxWidth-lineLength, false);
				}

			} else { /* line not long, continue */
				lineLength += token.value.length;
				if (token.value.indexOf(" ") != -1) { lastTokenWithSpace = i; }
			}
			
			i++; /* advance to next token */
		}


		tokens.push({type: ROT.Text.TYPE_NEWLINE}); /* insert fake newline to fix the last text line */

		/* remove trailing space from text tokens before newlines */
		var lastTextToken = null;
		for (var i=0;i<tokens.length;i++) {
			var token = tokens[i];
			switch (token.type) {
				case ROT.Text.TYPE_TEXT: lastTextToken = token; break;
				case ROT.Text.TYPE_NEWLINE: 
					if (lastTextToken) { /* remove trailing space */
						var arr = lastTextToken.value.split("");
						while (arr[arr.length-1] == " ") { arr.pop(); }
						lastTextToken.value = arr.join("");
					}
					lastTextToken = null;
				break;
			}
		}

		tokens.pop(); /* remove fake token */

		return tokens;
	},

	/**
	 * Create new tokens and insert them into the stream
	 * @param {object[]} tokens
	 * @param {int} tokenIndex Token being processed
	 * @param {int} breakIndex Index within current token's value
	 * @param {bool} removeBreakChar Do we want to remove the breaking character?
	 * @returns {string} remaining unbroken token value
	 */
	_breakInsideToken: function(tokens, tokenIndex, breakIndex, removeBreakChar) {
		var newBreakToken = {
			type: ROT.Text.TYPE_NEWLINE
		}
		var newTextToken = {
			type: ROT.Text.TYPE_TEXT,
			value: tokens[tokenIndex].value.substring(breakIndex + (removeBreakChar ? 1 : 0))
		}
		tokens.splice(tokenIndex+1, 0, newBreakToken, newTextToken);
		return tokens[tokenIndex].value.substring(0, breakIndex);
	}
}
/**
 * @returns {any} Randomly picked item, null when length=0
 */
Array.prototype.random = function() {
	if (!this.length) { return null; }
	return this[Math.floor(ROT.RNG.getUniform() * this.length)];
}

/**
 * @returns {array} New array with randomized items
 * FIXME destroys this!
 */
Array.prototype.randomize = function() {
	var result = [];
	while (this.length) {
		var index = this.indexOf(this.random());
		result.push(this.splice(index, 1)[0]);
	}
	return result;
}
/**
 * Always positive modulus
 * @param {int} n Modulus
 * @returns {int} this modulo n
 */
Number.prototype.mod = function(n) {
	return ((this%n)+n)%n;
}
/**
 * @returns {string} First letter capitalized
 */
String.prototype.capitalize = function() {
	return this.charAt(0).toUpperCase() + this.substring(1);
}

/** 
 * Left pad
 * @param {string} [character="0"]
 * @param {int} [count=2]
 */
String.prototype.lpad = function(character, count) {
	var ch = character || "0";
	var cnt = count || 2;

	var s = "";
	while (s.length < (cnt - this.length)) { s += ch; }
	s = s.substring(0, cnt-this.length);
	return s+this;
}

/** 
 * Right pad
 * @param {string} [character="0"]
 * @param {int} [count=2]
 */
String.prototype.rpad = function(character, count) {
	var ch = character || "0";
	var cnt = count || 2;

	var s = "";
	while (s.length < (cnt - this.length)) { s += ch; }
	s = s.substring(0, cnt-this.length);
	return this+s;
}

/**
 * Format a string in a flexible way. Scans for %s strings and replaces them with arguments. List of patterns is modifiable via String.format.map.
 * @param {string} template
 * @param {any} [argv]
 */
String.format = function(template) {
	var map = String.format.map;
	var args = Array.prototype.slice.call(arguments, 1);

	var replacer = function(match, group1, group2, index) {
		if (template.charAt(index-1) == "%") { return match.substring(1); }
		if (!args.length) { return match; }
		var obj = args[0];

		var group = group1 || group2;
		var parts = group.split(",");
		var name = parts.shift();
		var method = map[name.toLowerCase()];
		if (!method) { return match; }

		var obj = args.shift();
		var replaced = obj[method].apply(obj, parts);

		var first = name.charAt(0);
		if (first != first.toLowerCase()) { replaced = replaced.capitalize(); }

		return replaced;
	}
	return template.replace(/%(?:([a-z]+)|(?:{([^}]+)}))/gi, replacer);
}

String.format.map = {
	"s": "toString"
}

/**
 * Convenience shortcut to String.format(this)
 */
String.prototype.format = function() {
	var args = Array.prototype.slice.call(arguments);
	args.unshift(this);
	return String.format.apply(String, args);
}

if (!Object.create) {  
	/**
	 * ES5 Object.create
	 */
	Object.create = function(o) {  
		var tmp = function() {};
		tmp.prototype = o;
		return new tmp();
	};  
}  
/**
 * Sets prototype of this function to an instance of parent function
 * @param {function} parent
 */
Function.prototype.extend = function(parent) {
	this.prototype = Object.create(parent.prototype);
	this.prototype.constructor = this;
	return this;
}
window.requestAnimationFrame =
	window.requestAnimationFrame
	|| window.mozRequestAnimationFrame
	|| window.webkitRequestAnimationFrame
	|| window.oRequestAnimationFrame
	|| window.msRequestAnimationFrame
	|| function(cb) { return setTimeout(cb, 1000/60); };

window.cancelAnimationFrame =
	window.cancelAnimationFrame
	|| window.mozCancelAnimationFrame
	|| window.webkitCancelAnimationFrame
	|| window.oCancelAnimationFrame
	|| window.msCancelAnimationFrame
	|| function(id) { return clearTimeout(id); };
/**
 * @class Visual map display
 * @param {object} [options]
 * @param {int} [options.width=ROT.DEFAULT_WIDTH]
 * @param {int} [options.height=ROT.DEFAULT_HEIGHT]
 * @param {int} [options.fontSize=15]
 * @param {string} [options.fontFamily="monospace"]
 * @param {string} [options.fontStyle=""] bold/italic/none/both
 * @param {string} [options.fg="#ccc"]
 * @param {string} [options.bg="#000"]
 * @param {float} [options.spacing=1]
 * @param {float} [options.border=0]
 * @param {string} [options.layout="rect"]
 * @param {int} [options.tileWidth=32]
 * @param {int} [options.tileHeight=32]
 * @param {object} [options.tileMap={}]
 * @param {image} [options.tileSet=null]
 */
ROT.Display = function(options) {
	var canvas = document.createElement("canvas");
	this._context = canvas.getContext("2d");
	this._data = {};
	this._dirty = false; /* false = nothing, true = all, object = dirty cells */
	this._options = {};
	this._backend = null;
	
	var defaultOptions = {
		width: ROT.DEFAULT_WIDTH,
		height: ROT.DEFAULT_HEIGHT,
		layout: "rect",
		fontSize: 15,
		spacing: 1,
		border: 0,
		fontFamily: "monospace",
		fontStyle: "",
		fg: "#ccc",
		bg: "#000",
		tileWidth: 32,
		tileHeight: 32,
		tileMap: {},
		tileSet: null
	};
	for (var p in options) { defaultOptions[p] = options[p]; }
	this.setOptions(defaultOptions);
	this.DEBUG = this.DEBUG.bind(this);

	this._tick = this._tick.bind(this);
	requestAnimationFrame(this._tick);
}

/**
 * Debug helper, ideal as a map generator callback. Always bound to this.
 * @param {int} x
 * @param {int} y
 * @param {int} what
 */
ROT.Display.prototype.DEBUG = function(x, y, what) {
	var colors = [this._options.bg, this._options.fg];
	this.draw(x, y, null, null, colors[what % colors.length]);
}

/**
 * Clear the whole display (cover it with background color)
 */
ROT.Display.prototype.clear = function() {
	this._data = {};
	this._dirty = true;
}

/**
 * @see ROT.Display
 */
ROT.Display.prototype.setOptions = function(options) {
	for (var p in options) { this._options[p] = options[p]; }
	if (options.width || options.height || options.fontSize || options.fontFamily || options.spacing || options.layout) {
		if (options.layout) { 
			this._backend = new ROT.Display[options.layout.capitalize()](this._context);
		}

		var font = (this._options.fontStyle ? this._options.fontStyle + " " : "") + this._options.fontSize + "px " + this._options.fontFamily;
		this._context.font = font;
		this._backend.compute(this._options);
		this._context.font = font;
		this._context.textAlign = "center";
		this._context.textBaseline = "middle";
		this._dirty = true;
	}
	return this;
}

/**
 * Returns currently set options
 * @returns {object} Current options object 
 */
ROT.Display.prototype.getOptions = function() {
	return this._options;
}

/**
 * Returns the DOM node of this display
 * @returns {node} DOM node
 */
ROT.Display.prototype.getContainer = function() {
	return this._context.canvas;
}

/**
 * Compute the maximum width/height to fit into a set of given constraints
 * @param {int} availWidth Maximum allowed pixel width
 * @param {int} availHeight Maximum allowed pixel height
 * @returns {int[2]} cellWidth,cellHeight
 */
ROT.Display.prototype.computeSize = function(availWidth, availHeight) {
	return this._backend.computeSize(availWidth, availHeight, this._options);
}

/**
 * Compute the maximum font size to fit into a set of given constraints
 * @param {int} availWidth Maximum allowed pixel width
 * @param {int} availHeight Maximum allowed pixel height
 * @returns {int} fontSize
 */
ROT.Display.prototype.computeFontSize = function(availWidth, availHeight) {
	return this._backend.computeFontSize(availWidth, availHeight, this._options);
}

/**
 * Convert a DOM event (mouse or touch) to map coordinates. Uses first touch for multi-touch.
 * @param {Event} e event
 * @returns {int[2]} -1 for values outside of the canvas
 */
ROT.Display.prototype.eventToPosition = function(e) {
	if (e.touches) {
		var x = e.touches[0].clientX;
		var y = e.touches[0].clientY;
	} else {
		var x = e.clientX;
		var y = e.clientY;
	}

	var rect = this._context.canvas.getBoundingClientRect();
	x -= rect.left;
	y -= rect.top;
	
	if (x < 0 || y < 0 || x >= this._context.canvas.width || y >= this._context.canvas.height) { return [-1, -1]; }

	return this._backend.eventToPosition(x, y);
}

/**
 * @param {int} x
 * @param {int} y
 * @param {string || string[]} ch One or more chars (will be overlapping themselves)
 * @param {string} [fg] foreground color
 * @param {string} [bg] background color
 */
ROT.Display.prototype.draw = function(x, y, ch, fg, bg) {
	if (!fg) { fg = this._options.fg; }
	if (!bg) { bg = this._options.bg; }
	this._data[x+","+y] = [x, y, ch, fg, bg];
	
	if (this._dirty === true) { return; } /* will already redraw everything */
	if (!this._dirty) { this._dirty = {}; } /* first! */
	this._dirty[x+","+y] = true;
}

/**
 * Draws a text at given position. Optionally wraps at a maximum length. Currently does not work with hex layout.
 * @param {int} x
 * @param {int} y
 * @param {string} text May contain color/background format specifiers, %c{name}/%b{name}, both optional. %c{}/%b{} resets to default.
 * @param {int} [maxWidth] wrap at what width?
 * @returns {int} lines drawn
 */
ROT.Display.prototype.drawText = function(x, y, text, maxWidth) {
	var fg = null;
	var bg = null;
	var cx = x;
	var cy = y;
	var lines = 1;
	if (!maxWidth) { maxWidth = this._options.width-x; }

	var tokens = ROT.Text.tokenize(text, maxWidth);

	while (tokens.length) { /* interpret tokenized opcode stream */
		var token = tokens.shift();
		switch (token.type) {
			case ROT.Text.TYPE_TEXT:
				for (var i=0;i<token.value.length;i++) {
					this.draw(cx++, cy, token.value.charAt(i), fg, bg);
				}
			break;

			case ROT.Text.TYPE_FG:
				fg = token.value || null;
			break;

			case ROT.Text.TYPE_BG:
				bg = token.value || null;
			break;

			case ROT.Text.TYPE_NEWLINE:
				cx = x;
				cy++;
				lines++
			break;
		}
	}

	return lines;
}

/**
 * Timer tick: update dirty parts
 */
ROT.Display.prototype._tick = function() {
	requestAnimationFrame(this._tick);

	if (!this._dirty) { return; }

	if (this._dirty === true) { /* draw all */
		this._context.fillStyle = this._options.bg;
		this._context.fillRect(0, 0, this._context.canvas.width, this._context.canvas.height);

		for (var id in this._data) { /* redraw cached data */
			this._draw(id, false);
		}

	} else { /* draw only dirty */
		for (var key in this._dirty) {
			this._draw(key, true);
		}
	}

	this._dirty = false;
}

/**
 * @param {string} key What to draw
 * @param {bool} clearBefore Is it necessary to clean before?
 */
ROT.Display.prototype._draw = function(key, clearBefore) {
	var data = this._data[key];
	if (data[4] != this._options.bg) { clearBefore = true; }

	this._backend.draw(data, clearBefore);
}
/**
 * @class Abstract display backend module
 * @private
 */
ROT.Display.Backend = function(context) {
	this._context = context;
}

ROT.Display.Backend.prototype.compute = function(options) {
}

ROT.Display.Backend.prototype.draw = function(data, clearBefore) {
}

ROT.Display.Backend.prototype.computeSize = function(availWidth, availHeight) {
}

ROT.Display.Backend.prototype.computeFontSize = function(availWidth, availHeight) {
}

ROT.Display.Backend.prototype.eventToPosition = function(x, y) {
}
/**
 * @class Rectangular backend
 * @private
 */
ROT.Display.Rect = function(context) {
	ROT.Display.Backend.call(this, context);
	
	this._spacingX = 0;
	this._spacingY = 0;
	this._canvasCache = {};
	this._options = {};
}
ROT.Display.Rect.extend(ROT.Display.Backend);

ROT.Display.Rect.cache = false;

ROT.Display.Rect.prototype.compute = function(options) {
	this._canvasCache = {};
	this._options = options;

	var charWidth = Math.ceil(this._context.measureText("W").width);
	this._spacingX = Math.ceil(options.spacing * charWidth);
	this._spacingY = Math.ceil(options.spacing * options.fontSize);
	this._context.canvas.width = options.width * this._spacingX;
	this._context.canvas.height = options.height * this._spacingY;
}

ROT.Display.Rect.prototype.draw = function(data, clearBefore) {
	if (this.constructor.cache) {
		this._drawWithCache(data, clearBefore);
	} else {
		this._drawNoCache(data, clearBefore);
	}
}

ROT.Display.Rect.prototype._drawWithCache = function(data, clearBefore) {
	var x = data[0];
	var y = data[1];
	var ch = data[2];
	var fg = data[3];
	var bg = data[4];

	var hash = ""+ch+fg+bg;
	if (hash in this._canvasCache) {
		var canvas = this._canvasCache[hash];
	} else {
		var b = this._options.border;
		var canvas = document.createElement("canvas");
		var ctx = canvas.getContext("2d");
		canvas.width = this._spacingX;
		canvas.height = this._spacingY;
		ctx.fillStyle = bg;
		ctx.fillRect(b, b, canvas.width-b, canvas.height-b);
		
		if (ch) {
			ctx.fillStyle = fg;
			ctx.font = this._context.font;
			ctx.textAlign = "center";
			ctx.textBaseline = "middle";

			var chars = [].concat(ch);
			for (var i=0;i<chars.length;i++) {
				ctx.fillText(chars[i], this._spacingX/2, this._spacingY/2);
			}
		}
		this._canvasCache[hash] = canvas;
	}
	
	this._context.drawImage(canvas, x*this._spacingX, y*this._spacingY);
}

ROT.Display.Rect.prototype._drawNoCache = function(data, clearBefore) {
	var x = data[0];
	var y = data[1];
	var ch = data[2];
	var fg = data[3];
	var bg = data[4];

	if (clearBefore) { 
		var b = this._options.border;
		this._context.fillStyle = bg;
		this._context.fillRect(x*this._spacingX + b, y*this._spacingY + b, this._spacingX - b, this._spacingY - b);
	}
	
	if (!ch) { return; }

	this._context.fillStyle = fg;

	var chars = [].concat(ch);
	for (var i=0;i<chars.length;i++) {
		this._context.fillText(chars[i], (x+0.5) * this._spacingX, (y+0.5) * this._spacingY);
	}
}

ROT.Display.Rect.prototype.computeSize = function(availWidth, availHeight) {
	var width = Math.floor(availWidth / this._spacingX);
	var height = Math.floor(availHeight / this._spacingY);
	return [width, height];
}

ROT.Display.Rect.prototype.computeFontSize = function(availWidth, availHeight) {
	var boxWidth = Math.floor(availWidth / this._options.width);
	var boxHeight = Math.floor(availHeight / this._options.height);

	/* compute char ratio */
	var oldFont = this._context.font;
	this._context.font = "100px " + this._options.fontFamily;
	var width = Math.ceil(this._context.measureText("W").width);
	this._context.font = oldFont;
	var ratio = width / 100;
		
	var widthFraction = ratio * boxHeight / boxWidth;
	if (widthFraction > 1) { /* too wide with current aspect ratio */
		boxHeight = Math.floor(boxHeight / widthFraction);
	}
	return Math.floor(boxHeight / this._options.spacing);
}

ROT.Display.Rect.prototype.eventToPosition = function(x, y) {
	return [Math.floor(x/this._spacingX), Math.floor(y/this._spacingY)];
}
/**
 * @class Hexagonal backend
 * @private
 */
ROT.Display.Hex = function(context) {
	ROT.Display.Backend.call(this, context);

	this._spacingX = 0;
	this._spacingY = 0;
	this._hexSize = 0;
	this._options = {};
}
ROT.Display.Hex.extend(ROT.Display.Backend);

ROT.Display.Hex.prototype.compute = function(options) {
	this._options = options;

	var charWidth = Math.ceil(this._context.measureText("W").width);
	this._hexSize = Math.floor(options.spacing * (options.fontSize + charWidth/Math.sqrt(3)) / 2);
	this._spacingX = this._hexSize * Math.sqrt(3) / 2;
	this._spacingY = this._hexSize * 1.5;
	this._context.canvas.width = Math.ceil( (options.width + 1) * this._spacingX );
	this._context.canvas.height = Math.ceil( (options.height - 1) * this._spacingY + 2*this._hexSize );
}

ROT.Display.Hex.prototype.draw = function(data, clearBefore) {
	var x = data[0];
	var y = data[1];
	var ch = data[2];
	var fg = data[3];
	var bg = data[4];

	var cx = (x+1) * this._spacingX;
	var cy = y * this._spacingY + this._hexSize;

	if (clearBefore) { 
		this._context.fillStyle = bg;
		this._fill(cx, cy);
	}
	
	if (!ch) { return; }

	this._context.fillStyle = fg;

	var chars = [].concat(ch);
	for (var i=0;i<chars.length;i++) {
		this._context.fillText(chars[i], cx, cy);
	}
}


ROT.Display.Hex.prototype.computeSize = function(availWidth, availHeight) {
	var width = Math.floor(availWidth / this._spacingX) - 1;
	var height = Math.floor((availHeight - 2*this._hexSize) / this._spacingY + 1);
	return [width, height];
}

ROT.Display.Hex.prototype.computeFontSize = function(availWidth, availHeight) {
	var hexSizeWidth = 2*availWidth / ((this._options.width+1) * Math.sqrt(3)) - 1;
	var hexSizeHeight = availHeight / (2 + 1.5*(this._options.height-1));
	var hexSize = Math.min(hexSizeWidth, hexSizeHeight);

	/* compute char ratio */
	var oldFont = this._context.font;
	this._context.font = "100px " + this._options.fontFamily;
	var width = Math.ceil(this._context.measureText("W").width);
	this._context.font = oldFont;
	var ratio = width / 100;

	hexSize = Math.floor(hexSize)+1; /* closest larger hexSize */

	var fontSize = 2*hexSize / (this._options.spacing * (1 + ratio / Math.sqrt(3)));

	/* closest smaller fontSize */
	return Math.ceil(fontSize)-1;
}

ROT.Display.Hex.prototype.eventToPosition = function(x, y) {
	var height = this._context.canvas.height / this._options.height;
	y = Math.floor(y/height);
	
	if (y.mod(2)) { /* odd row */
		x -= this._spacingX;
		x = 1 + 2*Math.floor(x/(2*this._spacingX));
	} else {
		x = 2*Math.floor(x/(2*this._spacingX));
	}
	
	return [x, y];
}

ROT.Display.Hex.prototype._fill = function(cx, cy) {
	var a = this._hexSize;
	var b = this._options.border;
	
	this._context.beginPath();
	this._context.moveTo(cx, cy-a+b);
	this._context.lineTo(cx + this._spacingX - b, cy-a/2+b);
	this._context.lineTo(cx + this._spacingX - b, cy+a/2-b);
	this._context.lineTo(cx, cy+a-b);
	this._context.lineTo(cx - this._spacingX + b, cy+a/2-b);
	this._context.lineTo(cx - this._spacingX + b, cy-a/2+b);
	this._context.lineTo(cx, cy-a+b);
	this._context.fill();
}
/**
 * @class Tile backend
 * @private
 */
ROT.Display.Tile = function(context) {
	ROT.Display.Rect.call(this, context);
	
	this._options = {};
}
ROT.Display.Tile.extend(ROT.Display.Rect);

ROT.Display.Tile.prototype.compute = function(options) {
	this._options = options;
	this._context.canvas.width = options.width * options.tileWidth;
	this._context.canvas.height = options.height * options.tileHeight;
}

ROT.Display.Tile.prototype.draw = function(data, clearBefore) {
	var x = data[0];
	var y = data[1];
	var ch = data[2];
	var fg = data[3];
	var bg = data[4];

	var tileWidth = this._options.tileWidth;
	var tileHeight = this._options.tileHeight;

	if (clearBefore) {
		var b = this._options.border;
		this._context.fillStyle = bg;
		this._context.fillRect(x*tileWidth, y*tileHeight, tileWidth, tileHeight);
	}

	if (!ch) { return; }

	var chars = [].concat(ch);
	for (var i=0;i<chars.length;i++) {
		var tile = this._options.tileMap[chars[i]];
		if (!tile) { throw new Error("Char '" + chars[i] + "' not found in tileMap"); }
		
		this._context.drawImage(
			this._options.tileSet,
			tile[0], tile[1], tileWidth, tileHeight,
			x*tileWidth, y*tileHeight, tileWidth, tileHeight
		);
	}
}

ROT.Display.Tile.prototype.computeSize = function(availWidth, availHeight) {
	var width = Math.floor(availWidth / this._options.tileWidth);
	var height = Math.floor(availHeight / this._options.tileHeight);
	return [width, height];
}

ROT.Display.Tile.prototype.computeFontSize = function(availWidth, availHeight) {
	var width = Math.floor(availWidth / this._options.width);
	var height = Math.floor(availHeight / this._options.height);
	return [width, height];
}
/**
 * @namespace
 * This code is an implementation of Alea algorithm; (C) 2010 Johannes Baagøe.
 * Alea is licensed according to the http://en.wikipedia.org/wiki/MIT_License.
 */
ROT.RNG = {
	/**
	 * @returns {number} 
	 */
	getSeed: function() {
		return this._seed;
	},

	/**
	 * @param {number} seed Seed the number generator
	 */
	setSeed: function(seed) {
		seed = (seed < 1 ? 1/seed : seed);

		this._seed = seed;
		this._s0 = (seed >>> 0) * this._frac;

		seed = (seed*69069 + 1) >>> 0;
		this._s1 = seed * this._frac;

		seed = (seed*69069 + 1) >>> 0;
		this._s2 = seed * this._frac;

		this._c = 1;
		return this;
	},

	/**
	 * @returns {float} Pseudorandom value [0,1), uniformly distributed
	 */
	getUniform: function() {
		var t = 2091639 * this._s0 + this._c * this._frac;
		this._s0 = this._s1;
		this._s1 = this._s2;
		this._c = t | 0;
		this._s2 = t - this._c;
		return this._s2;
	},

	/**
	 * @param {int} lowerBound The lower end of the range to return a value from, inclusive
	 * @param {int} upperBound The upper end of the range to return a value from, inclusive
	 * @returns {int} Pseudorandom value [lowerBound, upperBound], using ROT.RNG.getUniform() to distribute the value
	 */
	getUniformInt: function(lowerBound, upperBound) {
		var max = Math.max(lowerBound, upperBound);
		var min = Math.min(lowerBound, upperBound);
		return Math.floor(this.getUniform() * (max - min + 1)) + min;
	},

	/**
	 * @param {float} [mean=0] Mean value
	 * @param {float} [stddev=1] Standard deviation. ~95% of the absolute values will be lower than 2*stddev.
	 * @returns {float} A normally distributed pseudorandom value
	 */
	getNormal: function(mean, stddev) {
		do {
			var u = 2*this.getUniform()-1;
			var v = 2*this.getUniform()-1;
			var r = u*u + v*v;
		} while (r > 1 || r == 0);

		var gauss = u * Math.sqrt(-2*Math.log(r)/r);
		return (mean || 0) + gauss*(stddev || 1);
	},

	/**
	 * @returns {int} Pseudorandom value [1,100] inclusive, uniformly distributed
	 */
	getPercentage: function() {
		return 1 + Math.floor(this.getUniform()*100);
	},
	
	/**
	 * @param {object} data key=whatever, value=weight (relative probability)
	 * @returns {string} whatever
	 */
	getWeightedValue: function(data) {
		var avail = [];
		var total = 0;
		
		for (var id in data) {
			total += data[id];
		}
		var random = Math.floor(this.getUniform()*total);
		
		var part = 0;
		for (var id in data) {
			part += data[id];
			if (random < part) { return id; }
		}
		
		return null;
	},

	/**
	 * Get RNG state. Useful for storing the state and re-setting it via setState.
	 * @returns {?} Internal state
	 */
	getState: function() {
		return [this._s0, this._s1, this._s2, this._c];
	},

	/**
	 * Set a previously retrieved state.
	 * @param {?} state
	 */
	setState: function(state) {
		this._s0 = state[0];
		this._s1 = state[1];
		this._s2 = state[2];
		this._c  = state[3];
		return this;
	},

	_s0: 0,
	_s1: 0,
	_s2: 0,
	_c: 0,
	_frac: 2.3283064365386963e-10 /* 2^-32 */
}

ROT.RNG.setSeed(Date.now());
/**
 * @class (Markov process)-based string generator. 
 * Copied from a <a href="http://www.roguebasin.roguelikedevelopment.org/index.php?title=Names_from_a_high_order_Markov_Process_and_a_simplified_Katz_back-off_scheme">RogueBasin article</a>. 
 * Offers configurable order and prior.
 * @param {object} [options]
 * @param {bool} [options.words=false] Use word mode?
 * @param {int} [options.order=3]
 * @param {float} [options.prior=0.001]
 */
ROT.StringGenerator = function(options) {
	this._options = {
		words: false,
		order: 3,
		prior: 0.001
	}
	for (var p in options) { this._options[p] = options[p]; }

	this._boundary = String.fromCharCode(0);
	this._suffix = this._boundary;
	this._prefix = [];
	for (var i=0;i<this._options.order;i++) { this._prefix.push(this._boundary); }

	this._priorValues = {};
	this._priorValues[this._boundary] = this._options.prior;

	this._data = {};
}

/**
 * Remove all learning data
 */
ROT.StringGenerator.prototype.clear = function() {
	this._data = {};
	this._priorValues = {};
}

/**
 * @returns {string} Generated string
 */
ROT.StringGenerator.prototype.generate = function() {
	var result = [this._sample(this._prefix)];
	while (result[result.length-1] != this._boundary) {
		result.push(this._sample(result));
	}
	return this._join(result.slice(0, -1));
}

/**
 * Observe (learn) a string from a training set
 */
ROT.StringGenerator.prototype.observe = function(string) {
	var tokens = this._split(string);

	for (var i=0; i<tokens.length; i++) {
		this._priorValues[tokens[i]] = this._options.prior;
	}

	tokens = this._prefix.concat(tokens).concat(this._suffix); /* add boundary symbols */

	for (var i=this._options.order; i<tokens.length; i++) {
		var context = tokens.slice(i-this._options.order, i);
		var event = tokens[i];
		for (var j=0; j<context.length; j++) {
			var subcontext = context.slice(j);
			this._observeEvent(subcontext, event);
		}
	}
}

ROT.StringGenerator.prototype.getStats = function() {
	var parts = [];

	var priorCount = 0;
	for (var p in this._priorValues) { priorCount++; }
	priorCount--; /* boundary */
	parts.push("distinct samples: " + priorCount);

	var dataCount = 0;
	var eventCount = 0;
	for (var p in this._data) { 
		dataCount++; 
		for (var key in this._data[p]) {
			eventCount++;
		}
	}
	parts.push("dictionary size (contexts): " + dataCount);
	parts.push("dictionary size (events): " + eventCount);

	return parts.join(", ");
}

/**
 * @param {string}
 * @returns {string[]}
 */
ROT.StringGenerator.prototype._split = function(str) {
	return str.split(this._options.words ? /\s+/ : "");
}

/**
 * @param {string[]}
 * @returns {string} 
 */
ROT.StringGenerator.prototype._join = function(arr) {
	return arr.join(this._options.words ? " " : "");
}

/**
 * @param {string[]} context
 * @param {string} event
 */
ROT.StringGenerator.prototype._observeEvent = function(context, event) {
	var key = this._join(context);
	if (!(key in this._data)) { this._data[key] = {}; }
	var data = this._data[key];

	if (!(event in data)) { data[event] = 0; }
	data[event]++;
}

/**
 * @param {string[]}
 * @returns {string}
 */
ROT.StringGenerator.prototype._sample = function(context) {
	context = this._backoff(context);
	var key = this._join(context);
	var data = this._data[key];

	var available = {};

	if (this._options.prior) {
		for (var event in this._priorValues) { available[event] = this._priorValues[event]; }
		for (var event in data) { available[event] += data[event]; }
	} else { 
		available = data;
	}

	return this._pickRandom(available);
}

/**
 * @param {string[]}
 * @returns {string[]}
 */
ROT.StringGenerator.prototype._backoff = function(context) {
	if (context.length > this._options.order) {
		context = context.slice(-this._options.order);
	} else if (context.length < this._options.order) {
		context = this._prefix.slice(0, this._options.order - context.length).concat(context);
	}

	while (!(this._join(context) in this._data) && context.length > 0) { context = context.slice(1); }

	return context;
}


ROT.StringGenerator.prototype._pickRandom = function(data) {
	var total = 0;
	
	for (var id in data) {
		total += data[id];
	}
	var random = ROT.RNG.getUniform()*total;
	
	var part = 0;
	for (var id in data) {
		part += data[id];
		if (random < part) { return id; }
	}
}
/**
 * @class Generic event queue: stores events and retrieves them based on their time
 */
ROT.EventQueue = function() {
	this._time = 0;
	this._events = [];
	this._eventTimes = [];
}

/**
 * @returns {number} Elapsed time
 */
ROT.EventQueue.prototype.getTime = function() {
	return this._time;
}

/**
 * Clear all scheduled events
 */
ROT.EventQueue.prototype.clear = function() {
	this._events = [];
	this._eventTimes = [];
	return this;
}

/**
 * @param {?} event
 * @param {number} time
 */
ROT.EventQueue.prototype.add = function(event, time) {
	var index = this._events.length;
	for (var i=0;i<this._eventTimes.length;i++) {
		if (this._eventTimes[i] > time) {
			index = i;
			break;
		}
	}

	this._events.splice(index, 0, event);
	this._eventTimes.splice(index, 0, time);
}

/**
 * Locates the nearest event, advances time if necessary. Returns that event and removes it from the queue.
 * @returns {? || null} The event previously added by addEvent, null if no event available
 */
ROT.EventQueue.prototype.get = function() {
	if (!this._events.length) { return null; }

	var time = this._eventTimes.splice(0, 1)[0];
	if (time > 0) { /* advance */
		this._time += time;
		for (var i=0;i<this._eventTimes.length;i++) { this._eventTimes[i] -= time; }
	}

	return this._events.splice(0, 1)[0];
}

/**
 * Remove an event from the queue
 * @param {?} event
 * @returns {bool} success?
 */
ROT.EventQueue.prototype.remove = function(event) {
	var index = this._events.indexOf(event);
	if (index == -1) { return false }
	this._remove(index);
	return true;
}

/**
 * Remove an event from the queue
 * @param {int} index
 */
ROT.EventQueue.prototype._remove = function(index) {
	this._events.splice(index, 1);
	this._eventTimes.splice(index, 1);
}
/**
 * @class Abstract scheduler
 */
ROT.Scheduler = function() {
	this._queue = new ROT.EventQueue();
	this._repeat = [];
	this._current = null;
}

/**
 * @see ROT.EventQueue#getTime
 */
ROT.Scheduler.prototype.getTime = function() {
	return this._queue.getTime();
}

/**
 * @param {?} item
 * @param {bool} repeat
 */
ROT.Scheduler.prototype.add = function(item, repeat) {
	if (repeat) { this._repeat.push(item); }
	return this;
}

/**
 * Clear all items
 */
ROT.Scheduler.prototype.clear = function() {
	this._queue.clear();
	this._repeat = [];
	this._current = null;
	return this;
}

/**
 * Remove a previously added item
 * @param {?} item
 * @returns {bool} successful?
 */
ROT.Scheduler.prototype.remove = function(item) {
	var result = this._queue.remove(item);

	var index = this._repeat.indexOf(item);
	if (index != -1) { this._repeat.splice(index, 1); }

	if (this._current == item) { this._current = null; }

	return result;
}

/**
 * Schedule next item
 * @returns {?}
 */
ROT.Scheduler.prototype.next = function() {
	this._current = this._queue.get();
	return this._current;
}
/**
 * @class Simple fair scheduler (round-robin style)
 * @augments ROT.Scheduler
 */
ROT.Scheduler.Simple = function() {
	ROT.Scheduler.call(this);
}
ROT.Scheduler.Simple.extend(ROT.Scheduler);

/**
 * @see ROT.Scheduler#add
 */
ROT.Scheduler.Simple.prototype.add = function(item, repeat) {
	this._queue.add(item, 0);
	return ROT.Scheduler.prototype.add.call(this, item, repeat);
}

/**
 * @see ROT.Scheduler#next
 */
ROT.Scheduler.Simple.prototype.next = function() {
	if (this._current && this._repeat.indexOf(this._current) != -1) {
		this._queue.add(this._current, 0);
	}
	return ROT.Scheduler.prototype.next.call(this);
}
/**
 * @class Speed-based scheduler
 * @augments ROT.Scheduler
 */
ROT.Scheduler.Speed = function() {
	ROT.Scheduler.call(this);
}
ROT.Scheduler.Speed.extend(ROT.Scheduler);

/**
 * @param {object} item anything with "getSpeed" method
 * @param {bool} repeat
 * @see ROT.Scheduler#add
 */
ROT.Scheduler.Speed.prototype.add = function(item, repeat) {
	this._queue.add(item, 1/item.getSpeed());
	return ROT.Scheduler.prototype.add.call(this, item, repeat);
}

/**
 * @see ROT.Scheduler#next
 */
ROT.Scheduler.Speed.prototype.next = function() {
	if (this._current && this._repeat.indexOf(this._current) != -1) {
		this._queue.add(this._current, 1/this._current.getSpeed());
	}
	return ROT.Scheduler.prototype.next.call(this);
}
/**
 * @class Action-based scheduler
 * @augments ROT.Scheduler
 */
ROT.Scheduler.Action = function() {
	ROT.Scheduler.call(this);
	this._defaultDuration = 1; /* for newly added */
	this._duration = this._defaultDuration; /* for this._current */
}
ROT.Scheduler.Action.extend(ROT.Scheduler);

/**
 * @param {object} item
 * @param {bool} repeat
 * @param {number} [time=1]
 * @see ROT.Scheduler#add
 */
ROT.Scheduler.Action.prototype.add = function(item, repeat, time) {
	this._queue.add(item, time || this._defaultDuration);
	return ROT.Scheduler.prototype.add.call(this, item, repeat);
}

ROT.Scheduler.Action.prototype.clear = function() {
	this._duration = this._defaultDuration;
	return ROT.Scheduler.prototype.clear.call(this);
}

ROT.Scheduler.Action.prototype.remove = function(item) {
	if (item == this._current) { this._duration = this._defaultDuration; }
	return ROT.Scheduler.prototype.remove.call(this, item);
}

/**
 * @see ROT.Scheduler#next
 */
ROT.Scheduler.Action.prototype.next = function() {
	if (this._current && this._repeat.indexOf(this._current) != -1) {
		this._queue.add(this._current, this._duration || this._defaultDuration);
		this._duration = this._defaultDuration;
	}
	return ROT.Scheduler.prototype.next.call(this);
}

/**
 * Set duration for the active item
 */
ROT.Scheduler.Action.prototype.setDuration = function(time) {
	if (this._current) { this._duration = time; }
	return this;
}
/**
 * @class Asynchronous main loop
 * @param {ROT.Scheduler} scheduler
 */
ROT.Engine = function(scheduler) {
	this._scheduler = scheduler;
	this._lock = 1;
}

/**
 * Start the main loop. When this call returns, the loop is locked.
 */
ROT.Engine.prototype.start = function() {
	return this.unlock();
}

/**
 * Interrupt the engine by an asynchronous action
 */
ROT.Engine.prototype.lock = function() {
	this._lock++;
	return this;
}

/**
 * Resume execution (paused by a previous lock)
 */
ROT.Engine.prototype.unlock = function() {
	if (!this._lock) { throw new Error("Cannot unlock unlocked engine"); }
	this._lock--;

	while (!this._lock) {
		var actor = this._scheduler.next();
		if (!actor) { return this.lock(); } /* no actors */
		var result = actor.act();
		if (result && result.then) { /* actor returned a "thenable", looks like a Promise */
			this.lock();
			result.then(this.unlock.bind(this));
		}
	}

	return this;
}
/**
 * @class Base map generator
 * @param {int} [width=ROT.DEFAULT_WIDTH]
 * @param {int} [height=ROT.DEFAULT_HEIGHT]
 */
ROT.Map = function(width, height) {
	this._width = width || ROT.DEFAULT_WIDTH;
	this._height = height || ROT.DEFAULT_HEIGHT;
};

ROT.Map.prototype.create = function(callback) {}

ROT.Map.prototype._fillMap = function(value) {
	var map = [];
	for (var i=0;i<this._width;i++) {
		map.push([]);
		for (var j=0;j<this._height;j++) { map[i].push(value); }
	}
	return map;
}
/**
 * @class Simple empty rectangular room
 * @augments ROT.Map
 */
ROT.Map.Arena = function(width, height) {
	ROT.Map.call(this, width, height);
}
ROT.Map.Arena.extend(ROT.Map);

ROT.Map.Arena.prototype.create = function(callback) {
	var w = this._width-1;
	var h = this._height-1;
	for (var i=0;i<=w;i++) {
		for (var j=0;j<=h;j++) {
			var empty = (i && j && i<w && j<h);
			callback(i, j, empty ? 0 : 1);
		}
	}
	return this;
}
/**
 * @class Recursively divided maze, http://en.wikipedia.org/wiki/Maze_generation_algorithm#Recursive_division_method
 * @augments ROT.Map
 */
ROT.Map.DividedMaze = function(width, height) {
	ROT.Map.call(this, width, height);
	this._stack = [];
}
ROT.Map.DividedMaze.extend(ROT.Map);

ROT.Map.DividedMaze.prototype.create = function(callback) {
	var w = this._width;
	var h = this._height;
	
	this._map = [];
	
	for (var i=0;i<w;i++) {
		this._map.push([]);
		for (var j=0;j<h;j++) {
			var border = (i == 0 || j == 0 || i+1 == w || j+1 == h);
			this._map[i].push(border ? 1 : 0);
		}
	}
	
	this._stack = [
		[1, 1, w-2, h-2]
	];
	this._process();
	
	for (var i=0;i<w;i++) {
		for (var j=0;j<h;j++) {
			callback(i, j, this._map[i][j]);
		}
	}
	this._map = null;
	return this;
}

ROT.Map.DividedMaze.prototype._process = function() {
	while (this._stack.length) {
		var room = this._stack.shift(); /* [left, top, right, bottom] */
		this._partitionRoom(room);
	}
}

ROT.Map.DividedMaze.prototype._partitionRoom = function(room) {
	var availX = [];
	var availY = [];
	
	for (var i=room[0]+1;i<room[2];i++) {
		var top = this._map[i][room[1]-1];
		var bottom = this._map[i][room[3]+1];
		if (top && bottom && !(i % 2)) { availX.push(i); }
	}
	
	for (var j=room[1]+1;j<room[3];j++) {
		var left = this._map[room[0]-1][j];
		var right = this._map[room[2]+1][j];
		if (left && right && !(j % 2)) { availY.push(j); }
	}

	if (!availX.length || !availY.length) { return; }

	var x = availX.random();
	var y = availY.random();
	
	this._map[x][y] = 1;
	
	var walls = [];
	
	var w = []; walls.push(w); /* left part */
	for (var i=room[0]; i<x; i++) { 
		this._map[i][y] = 1;
		w.push([i, y]); 
	}
	
	var w = []; walls.push(w); /* right part */
	for (var i=x+1; i<=room[2]; i++) { 
		this._map[i][y] = 1;
		w.push([i, y]); 
	}

	var w = []; walls.push(w); /* top part */
	for (var j=room[1]; j<y; j++) { 
		this._map[x][j] = 1;
		w.push([x, j]); 
	}
	
	var w = []; walls.push(w); /* bottom part */
	for (var j=y+1; j<=room[3]; j++) { 
		this._map[x][j] = 1;
		w.push([x, j]); 
	}
		
	var solid = walls.random();
	for (var i=0;i<walls.length;i++) {
		var w = walls[i];
		if (w == solid) { continue; }
		
		var hole = w.random();
		this._map[hole[0]][hole[1]] = 0;
	}

	this._stack.push([room[0], room[1], x-1, y-1]); /* left top */
	this._stack.push([x+1, room[1], room[2], y-1]); /* right top */
	this._stack.push([room[0], y+1, x-1, room[3]]); /* left bottom */
	this._stack.push([x+1, y+1, room[2], room[3]]); /* right bottom */
}
/**
 * @class Icey's Maze generator
 * See http://www.roguebasin.roguelikedevelopment.org/index.php?title=Simple_maze for explanation
 * @augments ROT.Map
 */
ROT.Map.IceyMaze = function(width, height, regularity) {
	ROT.Map.call(this, width, height);
	this._regularity = regularity || 0;
}
ROT.Map.IceyMaze.extend(ROT.Map);

ROT.Map.IceyMaze.prototype.create = function(callback) {
	var width = this._width;
	var height = this._height;
	
	var map = this._fillMap(1);
	
	width -= (width % 2 ? 1 : 2);
	height -= (height % 2 ? 1 : 2);

	var cx = 0;
	var cy = 0;
	var nx = 0;
	var ny = 0;

	var done = 0;
	var blocked = false;
	var dirs = [
		[0, 0],
		[0, 0],
		[0, 0],
		[0, 0]
	];
	do {
		cx = 1 + 2*Math.floor(ROT.RNG.getUniform()*(width-1) / 2);
		cy = 1 + 2*Math.floor(ROT.RNG.getUniform()*(height-1) / 2);

		if (!done) { map[cx][cy] = 0; }
		
		if (!map[cx][cy]) {
			this._randomize(dirs);
			do {
				if (Math.floor(ROT.RNG.getUniform()*(this._regularity+1)) == 0) { this._randomize(dirs); }
				blocked = true;
				for (var i=0;i<4;i++) {
					nx = cx + dirs[i][0]*2;
					ny = cy + dirs[i][1]*2;
					if (this._isFree(map, nx, ny, width, height)) {
						map[nx][ny] = 0;
						map[cx + dirs[i][0]][cy + dirs[i][1]] = 0;
						
						cx = nx;
						cy = ny;
						blocked = false;
						done++;
						break;
					}
				}
			} while (!blocked);
		}
	} while (done+1 < width*height/4);
	
	for (var i=0;i<this._width;i++) {
		for (var j=0;j<this._height;j++) {
			callback(i, j, map[i][j]);
		}
	}
	this._map = null;
	return this;
}

ROT.Map.IceyMaze.prototype._randomize = function(dirs) {
	for (var i=0;i<4;i++) {
		dirs[i][0] = 0;
		dirs[i][1] = 0;
	}
	
	switch (Math.floor(ROT.RNG.getUniform()*4)) {
		case 0:
			dirs[0][0] = -1; dirs[1][0] = 1;
			dirs[2][1] = -1; dirs[3][1] = 1;
		break;
		case 1:
			dirs[3][0] = -1; dirs[2][0] = 1;
			dirs[1][1] = -1; dirs[0][1] = 1;
		break;
		case 2:
			dirs[2][0] = -1; dirs[3][0] = 1;
			dirs[0][1] = -1; dirs[1][1] = 1;
		break;
		case 3:
			dirs[1][0] = -1; dirs[0][0] = 1;
			dirs[3][1] = -1; dirs[2][1] = 1;
		break;
	}
}

ROT.Map.IceyMaze.prototype._isFree = function(map, x, y, width, height) {
	if (x < 1 || y < 1 || x >= width || y >= height) { return false; }
	return map[x][y];
}
/**
 * @class Maze generator - Eller's algorithm
 * See http://homepages.cwi.nl/~tromp/maze.html for explanation
 * @augments ROT.Map
 */
ROT.Map.EllerMaze = function(width, height) {
	ROT.Map.call(this, width, height);
}
ROT.Map.EllerMaze.extend(ROT.Map);

ROT.Map.EllerMaze.prototype.create = function(callback) {
	var map = this._fillMap(1);
	var w = Math.ceil((this._width-2)/2);
	
	var rand = 9/24;
	
	var L = [];
	var R = [];
	
	for (var i=0;i<w;i++) {
		L.push(i);
		R.push(i);
	}
	L.push(w-1); /* fake stop-block at the right side */

	for (var j=1;j+3<this._height;j+=2) {
		/* one row */
		for (var i=0;i<w;i++) {
			/* cell coords (will be always empty) */
			var x = 2*i+1;
			var y = j;
			map[x][y] = 0;
			
			/* right connection */
			if (i != L[i+1] && ROT.RNG.getUniform() > rand) {
				this._addToList(i, L, R);
				map[x+1][y] = 0;
			}
			
			/* bottom connection */
			if (i != L[i] && ROT.RNG.getUniform() > rand) {
				/* remove connection */
				this._removeFromList(i, L, R);
			} else {
				/* create connection */
				map[x][y+1] = 0;
			}
		}
	}

	/* last row */
	for (var i=0;i<w;i++) {
		/* cell coords (will be always empty) */
		var x = 2*i+1;
		var y = j;
		map[x][y] = 0;
		
		/* right connection */
		if (i != L[i+1] && (i == L[i] || ROT.RNG.getUniform() > rand)) {
			/* dig right also if the cell is separated, so it gets connected to the rest of maze */
			this._addToList(i, L, R);
			map[x+1][y] = 0;
		}
		
		this._removeFromList(i, L, R);
	}
	
	for (var i=0;i<this._width;i++) {
		for (var j=0;j<this._height;j++) {
			callback(i, j, map[i][j]);
		}
	}
	
	return this;
}

/**
 * Remove "i" from its list
 */
ROT.Map.EllerMaze.prototype._removeFromList = function(i, L, R) {
	R[L[i]] = R[i];
	L[R[i]] = L[i];
	R[i] = i;
	L[i] = i;
}

/**
 * Join lists with "i" and "i+1"
 */
ROT.Map.EllerMaze.prototype._addToList = function(i, L, R) {
	R[L[i+1]] = R[i];
	L[R[i]] = L[i+1];
	R[i] = i+1;
	L[i+1] = i;
}
/**
 * @class Cellular automaton map generator
 * @augments ROT.Map
 * @param {int} [width=ROT.DEFAULT_WIDTH]
 * @param {int} [height=ROT.DEFAULT_HEIGHT]
 * @param {object} [options] Options
 * @param {int[]} [options.born] List of neighbor counts for a new cell to be born in empty space
 * @param {int[]} [options.survive] List of neighbor counts for an existing  cell to survive
 * @param {int} [options.topology] Topology 4 or 6 or 8
 */
ROT.Map.Cellular = function(width, height, options) {
	ROT.Map.call(this, width, height);
	this._options = {
		born: [5, 6, 7, 8],
		survive: [4, 5, 6, 7, 8],
		topology: 8,
		connected: false
	};
	this.setOptions(options);
	
	this._dirs = ROT.DIRS[this._options.topology];
	this._map = this._fillMap(0);
}
ROT.Map.Cellular.extend(ROT.Map);

/**
 * Fill the map with random values
 * @param {float} probability Probability for a cell to become alive; 0 = all empty, 1 = all full
 */
ROT.Map.Cellular.prototype.randomize = function(probability) {
	for (var i=0;i<this._width;i++) {
		for (var j=0;j<this._height;j++) {
			this._map[i][j] = (ROT.RNG.getUniform() < probability ? 1 : 0);
		}
	}
	return this;
}

/**
 * Change options.
 * @see ROT.Map.Cellular
 */
ROT.Map.Cellular.prototype.setOptions = function(options) {
	for (var p in options) { this._options[p] = options[p]; }
}

ROT.Map.Cellular.prototype.set = function(x, y, value) {
	this._map[x][y] = value;
}

ROT.Map.Cellular.prototype.create = function(callback) {
	var newMap = this._fillMap(0);
	var born = this._options.born;
	var survive = this._options.survive;


	for (var j=0;j<this._height;j++) {
		var widthStep = 1;
		var widthStart = 0;
		if (this._options.topology == 6) { 
			widthStep = 2;
			widthStart = j%2;
		}

		for (var i=widthStart; i<this._width; i+=widthStep) {

			var cur = this._map[i][j];
			var ncount = this._getNeighbors(i, j);
			
			if (cur && survive.indexOf(ncount) != -1) { /* survive */
				newMap[i][j] = 1;
			} else if (!cur && born.indexOf(ncount) != -1) { /* born */
				newMap[i][j] = 1;
			}			
		}
	}
	
	this._map = newMap;

	// optinially connect every space
	if (this._options.connected) {
		this._completeMaze();	
	}

	if (callback) { 
		for (var i = 0; i < this._width; i++) {
			for (var j = 0; j < this._height; j++) {
				callback(i, j, newMap[i][j]);
			}
		}
	}
}

/**
 * Get neighbor count at [i,j] in this._map
 */
ROT.Map.Cellular.prototype._getNeighbors = function(cx, cy) {
	var result = 0;
	for (var i=0;i<this._dirs.length;i++) {
		var dir = this._dirs[i];
		var x = cx + dir[0];
		var y = cy + dir[1];
		
		if (x < 0 || x >= this._width || x < 0 || y >= this._width) { continue; }
		result += (this._map[x][y] == 1 ? 1 : 0);
	}
	
	return result;
}

/**
 * Make sure every non-wall space is accessible.
 */
ROT.Map.Cellular.prototype._completeMaze = function() {
	var allFreeSpace = [];
	var notConnected = {};
	// find all free space
	for (var x = 0; x < this._width; x++) {
		for (var y = 0; y < this._height; y++) {
			if (this._freeSpace(x, y)) {
				var p = [x, y];
				notConnected[this._pointKey(p)] = p;
				allFreeSpace.push([x, y]);
			}
		}
	}
	var start = allFreeSpace[ROT.RNG.getUniformInt(0, allFreeSpace.length - 1)];

	var key = this._pointKey(start);
	var connected = {};
	connected[key] = start;
	delete notConnected[key]

	// find what's connected to the starting point
	this._findConnected(connected, notConnected, [start]);

	while(Object.keys(notConnected).length > 0) {

		// find two points from notConnected to connected
		var p = this._getFromTo(connected, notConnected);
		var from = p[0]; // notConnected
		var to = p[1]; // connected

		// find everything connected to the starting point
		var local = {};
		local[this._pointKey(from)] = from;
		this._findConnected(local, notConnected, [from], true);

		// connect to a connected square
		this._tunnelToConnected(to, from, connected, notConnected);

		// now all of local is connected
		for (var k in local) {
			var pp = local[k];
			this._map[pp[0]][pp[1]] = 0;
			connected[k] = pp;
			delete notConnected[k];
		}
	}
}

/**
 * Find random points to connect. Search for the closest point in the larger space. 
 * This is to minimize the length of the passage while maintaining good performance.
 */
ROT.Map.Cellular.prototype._getFromTo = function(connected, notConnected) {
	var from, to, d;
	var connectedKeys = Object.keys(connected);
	var notConnectedKeys = Object.keys(notConnected);
	for (var i = 0; i < 5; i++) {
		if (connectedKeys.length < notConnectedKeys.length) {
			var keys = connectedKeys;
			to = connected[keys[ROT.RNG.getUniformInt(0, keys.length - 1)]]
			from = this._getClosest(to, notConnected);
		} else {
			var keys = notConnectedKeys;
			from = notConnected[keys[ROT.RNG.getUniformInt(0, keys.length - 1)]]
			to = this._getClosest(from, connected);
		}
		d = (from[0] - to[0]) * (from[0] - to[0]) + (from[1] - to[1]) * (from[1] - to[1]);
		if (d < 64) {
			break;
		}
	}
	// console.log(">>> connected=" + to + " notConnected=" + from + " dist=" + d);
	return [from, to];
}

ROT.Map.Cellular.prototype._getClosest = function(point, space) {
	var minPoint = null;
	var minDist = null;
	for (k in space) {
		var p = space[k];
		var d = (p[0] - point[0]) * (p[0] - point[0]) + (p[1] - point[1]) * (p[1] - point[1]);
		if (minDist == null || d < minDist) {
			minDist = d;
			minPoint = p;
		}
	}
	return minPoint;
}

ROT.Map.Cellular.prototype._findConnected = function(connected, notConnected, stack, keepNotConnected) {
	while(stack.length > 0) {
		var p = stack.splice(0, 1)[0];
		var tests = [
			[p[0] + 1, p[1]],
			[p[0] - 1, p[1]],
			[p[0],     p[1] + 1],
			[p[0],     p[1] - 1]
		];
		for (var i = 0; i < tests.length; i++) {
			var key = this._pointKey(tests[i]);
			if (connected[key] == null && this._freeSpace(tests[i][0], tests[i][1])) {
				connected[key] = tests[i];
				if (!keepNotConnected) {
					delete notConnected[key];
				}
				stack.push(tests[i]);
			}
		}
	}
}

ROT.Map.Cellular.prototype._tunnelToConnected = function(to, from, connected, notConnected) {
	var key = this._pointKey(from);
	var a, b;
	if (from[0] < to[0]) {
		a = from;
		b = to;
	} else {
		a = to;
		b = from;
	}
	for (var xx = a[0]; xx <= b[0]; xx++) {
		this._map[xx][a[1]] = 0;
		var p = [xx, a[1]];
		var pkey = this._pointKey(p);
		connected[pkey] = p;
		delete notConnected[pkey];
	}

	// x is now fixed
	var x = b[0];

	if (from[1] < to[1]) {
		a = from;
		b = to;
	} else {
		a = to;
		b = from;
	}
	for (var yy = a[1]; yy < b[1]; yy++) {
		this._map[x][yy] = 0;
		var p = [x, yy];
		var pkey = this._pointKey(p);
		connected[pkey] = p;
		delete notConnected[pkey];
	}
}

ROT.Map.Cellular.prototype._freeSpace = function(x, y) {
	return x >= 0 && x < this._width && y >= 0 && y < this._height && this._map[x][y] != 1;
}

ROT.Map.Cellular.prototype._pointKey = function(p) {
	return p[0] + "." + p[1];
}

/**
 * @class Dungeon map: has rooms and corridors
 * @augments ROT.Map
 */
ROT.Map.Dungeon = function(width, height) {
	ROT.Map.call(this, width, height);
	this._rooms = []; /* list of all rooms */
	this._corridors = [];
}
ROT.Map.Dungeon.extend(ROT.Map);

/**
 * Get all generated rooms
 * @returns {ROT.Map.Feature.Room[]}
 */
ROT.Map.Dungeon.prototype.getRooms = function() {
	return this._rooms;
}

/**
 * Get all generated corridors
 * @returns {ROT.Map.Feature.Corridor[]}
 */
ROT.Map.Dungeon.prototype.getCorridors = function() {
	return this._corridors;
}
/**
 * @class Random dungeon generator using human-like digging patterns.
 * Heavily based on Mike Anderson's ideas from the "Tyrant" algo, mentioned at 
 * http://www.roguebasin.roguelikedevelopment.org/index.php?title=Dungeon-Building_Algorithm.
 * @augments ROT.Map.Dungeon
 */
ROT.Map.Digger = function(width, height, options) {
	ROT.Map.Dungeon.call(this, width, height);
	
	this._options = {
		roomWidth: [3, 9], /* room minimum and maximum width */
		roomHeight: [3, 5], /* room minimum and maximum height */
		corridorLength: [3, 10], /* corridor minimum and maximum length */
		dugPercentage: 0.2, /* we stop after this percentage of level area has been dug out */
		timeLimit: 1000 /* we stop after this much time has passed (msec) */
	}
	for (var p in options) { this._options[p] = options[p]; }
	
	this._features = {
		"Room": 4,
		"Corridor": 4
	}
	this._featureAttempts = 20; /* how many times do we try to create a feature on a suitable wall */
	this._walls = {}; /* these are available for digging */
	
	this._digCallback = this._digCallback.bind(this);
	this._canBeDugCallback = this._canBeDugCallback.bind(this);
	this._isWallCallback = this._isWallCallback.bind(this);
	this._priorityWallCallback = this._priorityWallCallback.bind(this);
}
ROT.Map.Digger.extend(ROT.Map.Dungeon);

/**
 * Create a map
 * @see ROT.Map#create
 */
ROT.Map.Digger.prototype.create = function(callback) {
	this._rooms = [];
	this._corridors = [];
	this._map = this._fillMap(1);
	this._walls = {};
	this._dug = 0;
	var area = (this._width-2) * (this._height-2);

	this._firstRoom();
	
	var t1 = Date.now();

	do {
		var t2 = Date.now();
		if (t2 - t1 > this._options.timeLimit) { break; }

		/* find a good wall */
		var wall = this._findWall();
		if (!wall) { break; } /* no more walls */
		
		var parts = wall.split(",");
		var x = parseInt(parts[0]);
		var y = parseInt(parts[1]);
		var dir = this._getDiggingDirection(x, y);
		if (!dir) { continue; } /* this wall is not suitable */
		
//		console.log("wall", x, y);

		/* try adding a feature */
		var featureAttempts = 0;
		do {
			featureAttempts++;
			if (this._tryFeature(x, y, dir[0], dir[1])) { /* feature added */
				//if (this._rooms.length + this._corridors.length == 2) { this._rooms[0].addDoor(x, y); } /* first room oficially has doors */
				this._removeSurroundingWalls(x, y);
				this._removeSurroundingWalls(x-dir[0], y-dir[1]);
				break; 
			}
		} while (featureAttempts < this._featureAttempts);
		
		var priorityWalls = 0;
		for (var id in this._walls) { 
			if (this._walls[id] > 1) { priorityWalls++; }
		}

	} while (this._dug/area < this._options.dugPercentage || priorityWalls); /* fixme number of priority walls */

	this._addDoors();

	if (callback) {
		for (var i=0;i<this._width;i++) {
			for (var j=0;j<this._height;j++) {
				callback(i, j, this._map[i][j]);
			}
		}
	}
	
	this._walls = {};
	this._map = null;

	return this;
}

ROT.Map.Digger.prototype._digCallback = function(x, y, value) {
	if (value == 0 || value == 2) { /* empty */
		this._map[x][y] = 0;
		this._dug++;
	} else { /* wall */
		this._walls[x+","+y] = 1;
	}
}

ROT.Map.Digger.prototype._isWallCallback = function(x, y) {
	if (x < 0 || y < 0 || x >= this._width || y >= this._height) { return false; }
	return (this._map[x][y] == 1);
}

ROT.Map.Digger.prototype._canBeDugCallback = function(x, y) {
	if (x < 1 || y < 1 || x+1 >= this._width || y+1 >= this._height) { return false; }
	return (this._map[x][y] == 1);
}

ROT.Map.Digger.prototype._priorityWallCallback = function(x, y) {
	this._walls[x+","+y] = 2;
}

ROT.Map.Digger.prototype._firstRoom = function() {
	var cx = Math.floor(this._width/2);
	var cy = Math.floor(this._height/2);
	var room = ROT.Map.Feature.Room.createRandomCenter(cx, cy, this._options);
	this._rooms.push(room);
	room.create(this._digCallback);
}

/**
 * Get a suitable wall
 */
ROT.Map.Digger.prototype._findWall = function() {
	var prio1 = [];
	var prio2 = [];
	for (var id in this._walls) {
		var prio = this._walls[id];
		if (prio == 2) { 
			prio2.push(id); 
		} else {
			prio1.push(id);
		}
	}
	
	var arr = (prio2.length ? prio2 : prio1);
	if (!arr.length) { return null; } /* no walls :/ */
	
	var id = arr.random();
	delete this._walls[id];

	return id;
}

/**
 * Tries adding a feature
 * @returns {bool} was this a successful try?
 */
ROT.Map.Digger.prototype._tryFeature = function(x, y, dx, dy) {
	var feature = ROT.RNG.getWeightedValue(this._features);
	feature = ROT.Map.Feature[feature].createRandomAt(x, y, dx, dy, this._options);
	
	if (!feature.isValid(this._isWallCallback, this._canBeDugCallback)) {
//		console.log("not valid");
//		feature.debug();
		return false;
	}
	
	feature.create(this._digCallback);
//	feature.debug();

	if (feature instanceof ROT.Map.Feature.Room) { this._rooms.push(feature); }
	if (feature instanceof ROT.Map.Feature.Corridor) { 
		feature.createPriorityWalls(this._priorityWallCallback);
		this._corridors.push(feature); 
	}
	
	return true;
}

ROT.Map.Digger.prototype._removeSurroundingWalls = function(cx, cy) {
	var deltas = ROT.DIRS[4];

	for (var i=0;i<deltas.length;i++) {
		var delta = deltas[i];
		var x = cx + delta[0];
		var y = cy + delta[1];
		delete this._walls[x+","+y];
		var x = cx + 2*delta[0];
		var y = cy + 2*delta[1];
		delete this._walls[x+","+y];
	}
}

/**
 * Returns vector in "digging" direction, or false, if this does not exist (or is not unique)
 */
ROT.Map.Digger.prototype._getDiggingDirection = function(cx, cy) {
	var result = null;
	var deltas = ROT.DIRS[4];
	
	for (var i=0;i<deltas.length;i++) {
		var delta = deltas[i];
		var x = cx + delta[0];
		var y = cy + delta[1];
		
		if (x < 0 || y < 0 || x >= this._width || y >= this._width) { return null; }
		
		if (!this._map[x][y]) { /* there already is another empty neighbor! */
			if (result) { return null; }
			result = delta;
		}
	}
	
	/* no empty neighbor */
	if (!result) { return null; }
	
	return [-result[0], -result[1]];
}

/**
 * Find empty spaces surrounding rooms, and apply doors.
 */
ROT.Map.Digger.prototype._addDoors = function() {
	var data = this._map;
	var isWallCallback = function(x, y) {
		return (data[x][y] == 1);
	}
	for (var i = 0; i < this._rooms.length; i++ ) {
		var room = this._rooms[i];
		room.clearDoors();
		room.addDoors(isWallCallback);
	}
}
/**
 * @class Dungeon generator which tries to fill the space evenly. Generates independent rooms and tries to connect them.
 * @augments ROT.Map.Dungeon
 */
ROT.Map.Uniform = function(width, height, options) {
	ROT.Map.Dungeon.call(this, width, height);

	this._options = {
		roomWidth: [3, 9], /* room minimum and maximum width */
		roomHeight: [3, 5], /* room minimum and maximum height */
		roomDugPercentage: 0.1, /* we stop after this percentage of level area has been dug out by rooms */
		timeLimit: 1000 /* we stop after this much time has passed (msec) */
	}
	for (var p in options) { this._options[p] = options[p]; }

	this._roomAttempts = 20; /* new room is created N-times until is considered as impossible to generate */
	this._corridorAttempts = 20; /* corridors are tried N-times until the level is considered as impossible to connect */

	this._connected = []; /* list of already connected rooms */
	this._unconnected = []; /* list of remaining unconnected rooms */
	
	this._digCallback = this._digCallback.bind(this);
	this._canBeDugCallback = this._canBeDugCallback.bind(this);
	this._isWallCallback = this._isWallCallback.bind(this);
}
ROT.Map.Uniform.extend(ROT.Map.Dungeon);

/**
 * Create a map. If the time limit has been hit, returns null.
 * @see ROT.Map#create
 */
ROT.Map.Uniform.prototype.create = function(callback) {
	var t1 = Date.now();
	while (1) {
		var t2 = Date.now();
		if (t2 - t1 > this._options.timeLimit) { return null; } /* time limit! */
	
		this._map = this._fillMap(1);
		this._dug = 0;
		this._rooms = [];
		this._unconnected = [];
		this._generateRooms();
		if (this._rooms.length < 2) { continue; }
		if (this._generateCorridors()) { break; }
	}
	
	if (callback) {
		for (var i=0;i<this._width;i++) {
			for (var j=0;j<this._height;j++) {
				callback(i, j, this._map[i][j]);
			}
		}
	}
	
	return this;
}

/**
 * Generates a suitable amount of rooms
 */
ROT.Map.Uniform.prototype._generateRooms = function() {
	var w = this._width-2;
	var h = this._height-2;

	do {
		var room = this._generateRoom();
		if (this._dug/(w*h) > this._options.roomDugPercentage) { break; } /* achieved requested amount of free space */
	} while (room);

	/* either enough rooms, or not able to generate more of them :) */
}

/**
 * Try to generate one room
 */
ROT.Map.Uniform.prototype._generateRoom = function() {
	var count = 0;
	while (count < this._roomAttempts) {
		count++;
		
		var room = ROT.Map.Feature.Room.createRandom(this._width, this._height, this._options);
		if (!room.isValid(this._isWallCallback, this._canBeDugCallback)) { continue; }
		
		room.create(this._digCallback);
		this._rooms.push(room);
		return room;
	} 

	/* no room was generated in a given number of attempts */
	return null;
}

/**
 * Generates connectors beween rooms
 * @returns {bool} success Was this attempt successfull?
 */
ROT.Map.Uniform.prototype._generateCorridors = function() {
	var cnt = 0;
	while (cnt < this._corridorAttempts) {
		cnt++;
		this._corridors = [];

		/* dig rooms into a clear map */
		this._map = this._fillMap(1);
		for (var i=0;i<this._rooms.length;i++) { 
			var room = this._rooms[i];
			room.clearDoors();
			room.create(this._digCallback); 
		}

		this._unconnected = this._rooms.slice().randomize();
		this._connected = [];
		if (this._unconnected.length) { this._connected.push(this._unconnected.pop()); } /* first one is always connected */
		
		while (1) {
			/* 1. pick random connected room */
			var connected = this._connected.random();
			
			/* 2. find closest unconnected */
			var room1 = this._closestRoom(this._unconnected, connected);
			
			/* 3. connect it to closest connected */
			var room2 = this._closestRoom(this._connected, room1);
			
			var ok = this._connectRooms(room1, room2);
			if (!ok) { break; } /* stop connecting, re-shuffle */
			
			if (!this._unconnected.length) { return true; } /* done; no rooms remain */
		}
	}
	return false;
}

/**
 * For a given room, find the closest one from the list
 */
ROT.Map.Uniform.prototype._closestRoom = function(rooms, room) {
	var dist = Infinity;
	var center = room.getCenter();
	var result = null;
	
	for (var i=0;i<rooms.length;i++) {
		var r = rooms[i];
		var c = r.getCenter();
		var dx = c[0]-center[0];
		var dy = c[1]-center[1];
		var d = dx*dx+dy*dy;
		
		if (d < dist) {
			dist = d;
			result = r;
		}
	}
	
	return result;
}

ROT.Map.Uniform.prototype._connectRooms = function(room1, room2) {
	/*
		room1.debug();
		room2.debug();
	*/

	var center1 = room1.getCenter();
	var center2 = room2.getCenter();

	var diffX = center2[0] - center1[0];
	var diffY = center2[1] - center1[1];

	if (Math.abs(diffX) < Math.abs(diffY)) { /* first try connecting north-south walls */
		var dirIndex1 = (diffY > 0 ? 2 : 0);
		var dirIndex2 = (dirIndex1 + 2) % 4;
		var min = room2.getLeft();
		var max = room2.getRight();
		var index = 0;
	} else { /* first try connecting east-west walls */
		var dirIndex1 = (diffX > 0 ? 1 : 3);
		var dirIndex2 = (dirIndex1 + 2) % 4;
		var min = room2.getTop();
		var max = room2.getBottom();
		var index = 1;
	}

	var start = this._placeInWall(room1, dirIndex1); /* corridor will start here */
	if (!start) { return false; }

	if (start[index] >= min && start[index] <= max) { /* possible to connect with straight line (I-like) */
		var end = start.slice();
		var value = null;
		switch (dirIndex2) {
			case 0: value = room2.getTop()-1; break;
			case 1: value = room2.getRight()+1; break;
			case 2: value = room2.getBottom()+1; break;
			case 3: value = room2.getLeft()-1; break;
		}
		end[(index+1)%2] = value;
		this._digLine([start, end]);
		
	} else if (start[index] < min-1 || start[index] > max+1) { /* need to switch target wall (L-like) */

		var diff = start[index] - center2[index];
		switch (dirIndex2) {
			case 0:
			case 1:	var rotation = (diff < 0 ? 3 : 1); break;
			case 2:
			case 3:	var rotation = (diff < 0 ? 1 : 3); break;
		}
		dirIndex2 = (dirIndex2 + rotation) % 4;
		
		var end = this._placeInWall(room2, dirIndex2);
		if (!end) { return false; }

		var mid = [0, 0];
		mid[index] = start[index];
		var index2 = (index+1)%2;
		mid[index2] = end[index2];
		this._digLine([start, mid, end]);
		
	} else { /* use current wall pair, but adjust the line in the middle (S-like) */
	
		var index2 = (index+1)%2;
		var end = this._placeInWall(room2, dirIndex2);
		if (!end) { return; }
		var mid = Math.round((end[index2] + start[index2])/2);

		var mid1 = [0, 0];
		var mid2 = [0, 0];
		mid1[index] = start[index];
		mid1[index2] = mid;
		mid2[index] = end[index];
		mid2[index2] = mid;
		this._digLine([start, mid1, mid2, end]);
	}

	room1.addDoor(start[0], start[1]);
	room2.addDoor(end[0], end[1]);
	
	var index = this._unconnected.indexOf(room1);
	if (index != -1) {
		this._unconnected.splice(index, 1);
		this._connected.push(room1);
	}

	var index = this._unconnected.indexOf(room2);
	if (index != -1) {
		this._unconnected.splice(index, 1);
		this._connected.push(room2);
	}
	
	return true;
}

ROT.Map.Uniform.prototype._placeInWall = function(room, dirIndex) {
	var start = [0, 0];
	var dir = [0, 0];
	var length = 0;
	
	switch (dirIndex) {
		case 0:
			dir = [1, 0];
			start = [room.getLeft(), room.getTop()-1];
			length = room.getRight()-room.getLeft()+1;
		break;
		case 1:
			dir = [0, 1];
			start = [room.getRight()+1, room.getTop()];
			length = room.getBottom()-room.getTop()+1;
		break;
		case 2:
			dir = [1, 0];
			start = [room.getLeft(), room.getBottom()+1];
			length = room.getRight()-room.getLeft()+1;
		break;
		case 3:
			dir = [0, 1];
			start = [room.getLeft()-1, room.getTop()];
			length = room.getBottom()-room.getTop()+1;
		break;
	}
	
	var avail = [];
	var lastBadIndex = -2;

	for (var i=0;i<length;i++) {
		var x = start[0] + i*dir[0];
		var y = start[1] + i*dir[1];
		avail.push(null);
		
		var isWall = (this._map[x][y] == 1);
		if (isWall) {
			if (lastBadIndex != i-1) { avail[i] = [x, y]; }
		} else {
			lastBadIndex = i;
			if (i) { avail[i-1] = null; }
		}
	}
	
	for (var i=avail.length-1; i>=0; i--) {
		if (!avail[i]) { avail.splice(i, 1); }
	}
	return (avail.length ? avail.random() : null);
}

/**
 * Dig a polyline.
 */
ROT.Map.Uniform.prototype._digLine = function(points) {
	for (var i=1;i<points.length;i++) {
		var start = points[i-1];
		var end = points[i];
		var corridor = new ROT.Map.Feature.Corridor(start[0], start[1], end[0], end[1]);
		corridor.create(this._digCallback);
		this._corridors.push(corridor);
	}
}

ROT.Map.Uniform.prototype._digCallback = function(x, y, value) {
	this._map[x][y] = value;
	if (value == 0) { this._dug++; }
}

ROT.Map.Uniform.prototype._isWallCallback = function(x, y) {
	if (x < 0 || y < 0 || x >= this._width || y >= this._height) { return false; }
	return (this._map[x][y] == 1);
}

ROT.Map.Uniform.prototype._canBeDugCallback = function(x, y) {
	if (x < 1 || y < 1 || x+1 >= this._width || y+1 >= this._height) { return false; }
	return (this._map[x][y] == 1);
}

/**
 * @author hyakugei
 * @class Dungeon generator which uses the "orginal" Rogue dungeon generation algorithm. See http://kuoi.com/~kamikaze/GameDesign/art07_rogue_dungeon.php
 * @augments ROT.Map
 * @param {int} [width=ROT.DEFAULT_WIDTH]
 * @param {int} [height=ROT.DEFAULT_HEIGHT]
 * @param {object} [options] Options
 * @param {int[]} [options.cellWidth=3] Number of cells to create on the horizontal (number of rooms horizontally)
 * @param {int[]} [options.cellHeight=3] Number of cells to create on the vertical (number of rooms vertically) 
 * @param {int} [options.roomWidth] Room min and max width - normally set auto-magically via the constructor.
 * @param {int} [options.roomHeight] Room min and max height - normally set auto-magically via the constructor. 
 */
ROT.Map.Rogue = function(width, height, options) {
	ROT.Map.call(this, width, height);
	
	this._options = {
		cellWidth: 3,  // NOTE to self, these could probably work the same as the roomWidth/room Height values
		cellHeight: 3  //     ie. as an array with min-max values for each direction....
	}
	
	for (var p in options) { this._options[p] = options[p]; }
	
	/*
	Set the room sizes according to the over-all width of the map, 
	and the cell sizes. 
	*/
	
	if (!this._options.hasOwnProperty("roomWidth")) {
		this._options["roomWidth"] = this._calculateRoomSize(width, this._options["cellWidth"]);
	}
	if (!this._options.hasOwnProperty["roomHeight"]) {
		this._options["roomHeight"] = this._calculateRoomSize(height, this._options["cellHeight"]);
	}
	
}

ROT.Map.Rogue.extend(ROT.Map); 

/**
 * @see ROT.Map#create
 */
ROT.Map.Rogue.prototype.create = function(callback) {
	this.map = this._fillMap(1);
	this.rooms = [];
	this.connectedCells = [];
	
	this._initRooms();
	this._connectRooms();
	this._connectUnconnectedRooms();
	this._createRandomRoomConnections();
	this._createRooms();
	this._createCorridors();
	
	if (callback) {
		for (var i = 0; i < this._width; i++) {
			for (var j = 0; j < this._height; j++) {
				callback(i, j, this.map[i][j]);   
			}
		}
	}
	
	return this;
}

ROT.Map.Rogue.prototype._getRandomInt = function(min, max) {
	return Math.floor(ROT.RNG.getUniform() * (max - min + 1)) + min;
}

ROT.Map.Rogue.prototype._calculateRoomSize = function(size, cell) {
	var max = Math.floor((size/cell) * 0.8);
	var min = Math.floor((size/cell) * 0.25);
	if (min < 2) min = 2;
	if (max < 2) max = 2;
	return [min, max];
}

ROT.Map.Rogue.prototype._initRooms = function () { 
	// create rooms array. This is the "grid" list from the algo.  
	for (var i = 0; i < this._options.cellWidth; i++) {  
		this.rooms.push([]);
		for(var j = 0; j < this._options.cellHeight; j++) {
			this.rooms[i].push({"x":0, "y":0, "width":0, "height":0, "connections":[], "cellx":i, "celly":j});
		}
	}
}

ROT.Map.Rogue.prototype._connectRooms = function() {
	//pick random starting grid
	var cgx = this._getRandomInt(0, this._options.cellWidth-1);
	var cgy = this._getRandomInt(0, this._options.cellHeight-1);
	
	var idx;
	var ncgx;
	var ncgy;
	
	var found = false;
	var room;
	var otherRoom;
	
	// find  unconnected neighbour cells
	do {
	
		//var dirToCheck = [0,1,2,3,4,5,6,7];
		var dirToCheck = [0,2,4,6];
		dirToCheck = dirToCheck.randomize();
		
		do {
			found = false;
			idx = dirToCheck.pop();
			
			
			ncgx = cgx + ROT.DIRS[8][idx][0];
			ncgy = cgy + ROT.DIRS[8][idx][1];
			
			if(ncgx < 0 || ncgx >= this._options.cellWidth) continue;
			if(ncgy < 0 || ncgy >= this._options.cellHeight) continue;
			
			room = this.rooms[cgx][cgy];
			
			if(room["connections"].length > 0)
			{
				// as long as this room doesn't already coonect to me, we are ok with it. 
				if(room["connections"][0][0] == ncgx &&
				room["connections"][0][1] == ncgy)
				{
					break;
				}
			}
			
			otherRoom = this.rooms[ncgx][ncgy];
			
			if (otherRoom["connections"].length == 0) { 
				otherRoom["connections"].push([cgx,cgy]);
				
				this.connectedCells.push([ncgx, ncgy]);
				cgx = ncgx;
				cgy = ncgy;
				found = true;
			}
					
		} while (dirToCheck.length > 0 && found == false)
		
	} while (dirToCheck.length > 0)

}

ROT.Map.Rogue.prototype._connectUnconnectedRooms = function() {
	//While there are unconnected rooms, try to connect them to a random connected neighbor 
	//(if a room has no connected neighbors yet, just keep cycling, you'll fill out to it eventually).
	var cw = this._options.cellWidth;
	var ch = this._options.cellHeight;
	
	var randomConnectedCell;
	this.connectedCells = this.connectedCells.randomize();
	var room;
	var otherRoom;
	var validRoom;
	
	for (var i = 0; i < this._options.cellWidth; i++) {
		for (var j = 0; j < this._options.cellHeight; j++)  {
				
			room = this.rooms[i][j];
			
			if (room["connections"].length == 0) {
				var directions = [0,2,4,6];
				directions = directions.randomize();
				
				var validRoom = false;
				
				do {
					
					var dirIdx = directions.pop();
					var newI = i + ROT.DIRS[8][dirIdx][0];
					var newJ = j + ROT.DIRS[8][dirIdx][1];
					
					if (newI < 0 || newI >= cw || 
					newJ < 0 || newJ >= ch) {
						continue;
					}
					
					otherRoom = this.rooms[newI][newJ];
					
					validRoom = true;
					
					if (otherRoom["connections"].length == 0) {
						break;
					}
					
					for (var k = 0; k < otherRoom["connections"].length; k++) {
						if(otherRoom["connections"][k][0] == i && 
						otherRoom["connections"][k][1] == j) {
							validRoom = false;
							break;
						}
					}
					
					if (validRoom) break;
					
				} while (directions.length)
				
				if(validRoom) { 
					room["connections"].push( [otherRoom["cellx"], otherRoom["celly"]] );  
				} else {
					console.log("-- Unable to connect room.");
				}
			}
		}
	}
}

ROT.Map.Rogue.prototype._createRandomRoomConnections = function(connections) {
	// Empty for now. 
}


ROT.Map.Rogue.prototype._createRooms = function() {
	// Create Rooms 
	
	var w = this._width;
	var h = this._height;
	
	var cw = this._options.cellWidth;
	var ch = this._options.cellHeight;
	
	var cwp = Math.floor(this._width / cw);
	var chp = Math.floor(this._height / ch);
	
	var roomw;
	var roomh;
	var roomWidth = this._options["roomWidth"];
	var roomHeight = this._options["roomHeight"];
	var sx;
	var sy;
	var tx;
	var ty;
	var otherRoom;
	
	for (var i = 0; i < cw; i++) {
		for (var j = 0; j < ch; j++) {
			sx = cwp * i;
			sy = chp * j;
			
			if (sx == 0) sx = 1;
			if (sy == 0) sy = 1;
			
			roomw = this._getRandomInt(roomWidth[0], roomWidth[1]);
			roomh = this._getRandomInt(roomHeight[0], roomHeight[1]);
			
			if (j > 0) {
				otherRoom = this.rooms[i][j-1];
				while (sy - (otherRoom["y"] + otherRoom["height"] ) < 3) {
					sy++;
				}
			}
			
			if (i > 0) {
				otherRoom = this.rooms[i-1][j];
				while(sx - (otherRoom["x"] + otherRoom["width"]) < 3) {
					sx++;
				}
			}
						
			var sxOffset = Math.round(this._getRandomInt(0, cwp-roomw)/2);
			var syOffset = Math.round(this._getRandomInt(0, chp-roomh)/2);
			
			while (sx + sxOffset + roomw >= w) {
				if(sxOffset) {
					sxOffset--;
				} else {
					roomw--; 
				}
			}
			
			while (sy + syOffset + roomh >= h) { 
				if(syOffset) {
					syOffset--;
				} else {
					roomh--; 
				}
			}
			
			sx = sx + sxOffset;
			sy = sy + syOffset;
			
			this.rooms[i][j]["x"] = sx;
			this.rooms[i][j]["y"] = sy;
			this.rooms[i][j]["width"] = roomw;
			this.rooms[i][j]["height"] = roomh;  
			
			for (var ii = sx; ii < sx + roomw; ii++) {
				for (var jj = sy; jj < sy + roomh; jj++) {
					this.map[ii][jj] = 0;
				}
			}  
		}
	}
}

ROT.Map.Rogue.prototype._getWallPosition = function(aRoom, aDirection) {
	var rx;
	var ry;
	var door;
	
	if (aDirection == 1 || aDirection == 3) {
		rx = this._getRandomInt(aRoom["x"] + 1, aRoom["x"] + aRoom["width"] - 2);
		if (aDirection == 1) {
			ry = aRoom["y"] - 2;
			door = ry + 1;
		} else {
			ry = aRoom["y"] + aRoom["height"] + 1;
			door = ry -1;
		}
		
		this.map[rx][door] = 0; // i'm not setting a specific 'door' tile value right now, just empty space. 
		
	} else if (aDirection == 2 || aDirection == 4) {
		ry = this._getRandomInt(aRoom["y"] + 1, aRoom["y"] + aRoom["height"] - 2);
		if(aDirection == 2) {
			rx = aRoom["x"] + aRoom["width"] + 1;
			door = rx - 1;
		} else {
			rx = aRoom["x"] - 2;
			door = rx + 1;
		}
		
		this.map[door][ry] = 0; // i'm not setting a specific 'door' tile value right now, just empty space. 
		
	}
	return [rx, ry];
}

/***
* @param startPosition a 2 element array
* @param endPosition a 2 element array
*/
ROT.Map.Rogue.prototype._drawCorridore = function (startPosition, endPosition) {
	var xOffset = endPosition[0] - startPosition[0];
	var yOffset = endPosition[1] - startPosition[1];
	
	var xpos = startPosition[0];
	var ypos = startPosition[1];
	
	var tempDist;
	var xDir;
	var yDir;
	
	var move; // 2 element array, element 0 is the direction, element 1 is the total value to move. 
	var moves = []; // a list of 2 element arrays
	
	var xAbs = Math.abs(xOffset);
	var yAbs = Math.abs(yOffset);
	
	var percent = ROT.RNG.getUniform(); // used to split the move at different places along the long axis
	var firstHalf = percent;
	var secondHalf = 1 - percent;
	
	xDir = xOffset > 0 ? 2 : 6;
	yDir = yOffset > 0 ? 4 : 0;
	
	if (xAbs < yAbs) {
		// move firstHalf of the y offset
		tempDist = Math.ceil(yAbs * firstHalf);
		moves.push([yDir, tempDist]);
		// move all the x offset
		moves.push([xDir, xAbs]);
		// move sendHalf of the  y offset
		tempDist = Math.floor(yAbs * secondHalf);
		moves.push([yDir, tempDist]);
	} else {
		//  move firstHalf of the x offset
		tempDist = Math.ceil(xAbs * firstHalf);
		moves.push([xDir, tempDist]);
		// move all the y offset
		moves.push([yDir, yAbs]);
		// move secondHalf of the x offset.
		tempDist = Math.floor(xAbs * secondHalf);
		moves.push([xDir, tempDist]);  
	}
	
	this.map[xpos][ypos] = 0;
	
	while (moves.length > 0) {
		move = moves.pop();
		while (move[1] > 0) {
			xpos += ROT.DIRS[8][move[0]][0];
			ypos += ROT.DIRS[8][move[0]][1];
			this.map[xpos][ypos] = 0;
			move[1] = move[1] - 1;
		}
	}
}

ROT.Map.Rogue.prototype._createCorridors = function () {
	// Draw Corridors between connected rooms
	
	var cw = this._options.cellWidth;
	var ch = this._options.cellHeight;
	var room;
	var connection;
	var otherRoom;
	var wall;
	var otherWall;
	
	for (var i = 0; i < cw; i++) {
		for (var j = 0; j < ch; j++) {
			room = this.rooms[i][j];
			
			for (var k = 0; k < room["connections"].length; k++) {
					
				connection = room["connections"][k]; 
				
				otherRoom = this.rooms[connection[0]][connection[1]];
				
				// figure out what wall our corridor will start one.
				// figure out what wall our corridor will end on. 
				if (otherRoom["cellx"] > room["cellx"] ) {
					wall = 2;
					otherWall = 4;
				} else if (otherRoom["cellx"] < room["cellx"] ) {
					wall = 4;
					otherWall = 2;
				} else if(otherRoom["celly"] > room["celly"]) {
					wall = 3;
					otherWall = 1;
				} else if(otherRoom["celly"] < room["celly"]) {
					wall = 1;
					otherWall = 3;
				}
				
				this._drawCorridore(this._getWallPosition(room, wall), this._getWallPosition(otherRoom, otherWall));
			}
		}
	}
}
/**
 * @class Dungeon feature; has own .create() method
 */
ROT.Map.Feature = function() {}
ROT.Map.Feature.prototype.isValid = function(canBeDugCallback) {}
ROT.Map.Feature.prototype.create = function(digCallback) {}
ROT.Map.Feature.prototype.debug = function() {}
ROT.Map.Feature.createRandomAt = function(x, y, dx, dy, options) {}

/**
 * @class Room
 * @augments ROT.Map.Feature
 * @param {int} x1
 * @param {int} y1
 * @param {int} x2
 * @param {int} y2
 * @param {int} [doorX]
 * @param {int} [doorY]
 */
ROT.Map.Feature.Room = function(x1, y1, x2, y2, doorX, doorY) {
	this._x1 = x1;
	this._y1 = y1;
	this._x2 = x2;
	this._y2 = y2;
	this._doors = {};
	if (arguments.length > 4) { this.addDoor(doorX, doorY); }
}
ROT.Map.Feature.Room.extend(ROT.Map.Feature);

/**
 * Room of random size, with a given doors and direction
 */
ROT.Map.Feature.Room.createRandomAt = function(x, y, dx, dy, options) {
	var min = options.roomWidth[0];
	var max = options.roomWidth[1];
	var width = min + Math.floor(ROT.RNG.getUniform()*(max-min+1));
	
	var min = options.roomHeight[0];
	var max = options.roomHeight[1];
	var height = min + Math.floor(ROT.RNG.getUniform()*(max-min+1));
	
	if (dx == 1) { /* to the right */
		var y2 = y - Math.floor(ROT.RNG.getUniform() * height);
		return new this(x+1, y2, x+width, y2+height-1, x, y);
	}
	
	if (dx == -1) { /* to the left */
		var y2 = y - Math.floor(ROT.RNG.getUniform() * height);
		return new this(x-width, y2, x-1, y2+height-1, x, y);
	}

	if (dy == 1) { /* to the bottom */
		var x2 = x - Math.floor(ROT.RNG.getUniform() * width);
		return new this(x2, y+1, x2+width-1, y+height, x, y);
	}

	if (dy == -1) { /* to the top */
		var x2 = x - Math.floor(ROT.RNG.getUniform() * width);
		return new this(x2, y-height, x2+width-1, y-1, x, y);
	}
}

/**
 * Room of random size, positioned around center coords
 */
ROT.Map.Feature.Room.createRandomCenter = function(cx, cy, options) {
	var min = options.roomWidth[0];
	var max = options.roomWidth[1];
	var width = min + Math.floor(ROT.RNG.getUniform()*(max-min+1));
	
	var min = options.roomHeight[0];
	var max = options.roomHeight[1];
	var height = min + Math.floor(ROT.RNG.getUniform()*(max-min+1));

	var x1 = cx - Math.floor(ROT.RNG.getUniform()*width);
	var y1 = cy - Math.floor(ROT.RNG.getUniform()*height);
	var x2 = x1 + width - 1;
	var y2 = y1 + height - 1;

	return new this(x1, y1, x2, y2);
}

/**
 * Room of random size within a given dimensions
 */
ROT.Map.Feature.Room.createRandom = function(availWidth, availHeight, options) {
	var min = options.roomWidth[0];
	var max = options.roomWidth[1];
	var width = min + Math.floor(ROT.RNG.getUniform()*(max-min+1));
	
	var min = options.roomHeight[0];
	var max = options.roomHeight[1];
	var height = min + Math.floor(ROT.RNG.getUniform()*(max-min+1));
	
	var left = availWidth - width - 1;
	var top = availHeight - height - 1;

	var x1 = 1 + Math.floor(ROT.RNG.getUniform()*left);
	var y1 = 1 + Math.floor(ROT.RNG.getUniform()*top);
	var x2 = x1 + width - 1;
	var y2 = y1 + height - 1;

	return new this(x1, y1, x2, y2);
}

ROT.Map.Feature.Room.prototype.addDoor = function(x, y) {
	this._doors[x+","+y] = 1;
	return this;
}

/**
 * @param {function}
 */
ROT.Map.Feature.Room.prototype.getDoors = function(callback) {
	for (var key in this._doors) {
		var parts = key.split(",");
		callback(parseInt(parts[0]), parseInt(parts[1]));
	}
	return this;
}

ROT.Map.Feature.Room.prototype.clearDoors = function() {
	this._doors = {};
	return this;
}

ROT.Map.Feature.Room.prototype.addDoors = function(isWallCallback) {
	var left = this._x1-1;
	var right = this._x2+1;
	var top = this._y1-1;
	var bottom = this._y2+1;

	for (var x=left; x<=right; x++) {
		for (var y=top; y<=bottom; y++) {
			if (x != left && x != right && y != top && y != bottom) { continue; }
			if (isWallCallback(x, y)) { continue; }

			this.addDoor(x, y);
		}
	}

	return this;
}

ROT.Map.Feature.Room.prototype.debug = function() {
	console.log("room", this._x1, this._y1, this._x2, this._y2);
}

ROT.Map.Feature.Room.prototype.isValid = function(isWallCallback, canBeDugCallback) { 
	var left = this._x1-1;
	var right = this._x2+1;
	var top = this._y1-1;
	var bottom = this._y2+1;
	
	for (var x=left; x<=right; x++) {
		for (var y=top; y<=bottom; y++) {
			if (x == left || x == right || y == top || y == bottom) {
				if (!isWallCallback(x, y)) { return false; }
			} else {
				if (!canBeDugCallback(x, y)) { return false; }
			}
		}
	}

	return true;
}

/**
 * @param {function} digCallback Dig callback with a signature (x, y, value). Values: 0 = empty, 1 = wall, 2 = door. Multiple doors are allowed.
 */
ROT.Map.Feature.Room.prototype.create = function(digCallback) { 
	var left = this._x1-1;
	var right = this._x2+1;
	var top = this._y1-1;
	var bottom = this._y2+1;
	
	var value = 0;
	for (var x=left; x<=right; x++) {
		for (var y=top; y<=bottom; y++) {
			if (x+","+y in this._doors) {
				value = 2;
			} else if (x == left || x == right || y == top || y == bottom) {
				value = 1;
			} else {
				value = 0;
			}
			digCallback(x, y, value);
		}
	}
}

ROT.Map.Feature.Room.prototype.getCenter = function() {
	return [Math.round((this._x1 + this._x2)/2), Math.round((this._y1 + this._y2)/2)];
}

ROT.Map.Feature.Room.prototype.getLeft = function() {
	return this._x1;
}

ROT.Map.Feature.Room.prototype.getRight = function() {
	return this._x2;
}

ROT.Map.Feature.Room.prototype.getTop = function() {
	return this._y1;
}

ROT.Map.Feature.Room.prototype.getBottom = function() {
	return this._y2;
}

/**
 * @class Corridor
 * @augments ROT.Map.Feature
 * @param {int} startX
 * @param {int} startY
 * @param {int} endX
 * @param {int} endY
 */
ROT.Map.Feature.Corridor = function(startX, startY, endX, endY) {
	this._startX = startX;
	this._startY = startY;
	this._endX = endX; 
	this._endY = endY;
	this._endsWithAWall = true;
}
ROT.Map.Feature.Corridor.extend(ROT.Map.Feature);

ROT.Map.Feature.Corridor.createRandomAt = function(x, y, dx, dy, options) {
	var min = options.corridorLength[0];
	var max = options.corridorLength[1];
	var length = min + Math.floor(ROT.RNG.getUniform()*(max-min+1));
	
	return new this(x, y, x + dx*length, y + dy*length);
}

ROT.Map.Feature.Corridor.prototype.debug = function() {
	console.log("corridor", this._startX, this._startY, this._endX, this._endY);
}

ROT.Map.Feature.Corridor.prototype.isValid = function(isWallCallback, canBeDugCallback){ 
	var sx = this._startX;
	var sy = this._startY;
	var dx = this._endX-sx;
	var dy = this._endY-sy;
	var length = 1 + Math.max(Math.abs(dx), Math.abs(dy));
	
	if (dx) { dx = dx/Math.abs(dx); }
	if (dy) { dy = dy/Math.abs(dy); }
	var nx = dy;
	var ny = -dx;
	
	var ok = true;
	for (var i=0; i<length; i++) {
		var x = sx + i*dx;
		var y = sy + i*dy;

		if (!canBeDugCallback(     x,      y)) { ok = false; }
		if (!isWallCallback  (x + nx, y + ny)) { ok = false; }
		if (!isWallCallback  (x - nx, y - ny)) { ok = false; }
		
		if (!ok) {
			length = i;
			this._endX = x-dx;
			this._endY = y-dy;
			break;
		}
	}
	
	/**
	 * If the length degenerated, this corridor might be invalid
	 */
	 
	/* not supported */
	if (length == 0) { return false; } 
	
	 /* length 1 allowed only if the next space is empty */
	if (length == 1 && isWallCallback(this._endX + dx, this._endY + dy)) { return false; }
	
	/**
	 * We do not want the corridor to crash into a corner of a room;
	 * if any of the ending corners is empty, the N+1th cell of this corridor must be empty too.
	 * 
	 * Situation:
	 * #######1
	 * .......?
	 * #######2
	 * 
	 * The corridor was dug from left to right.
	 * 1, 2 - problematic corners, ? = N+1th cell (not dug)
	 */
	var firstCornerBad = !isWallCallback(this._endX + dx + nx, this._endY + dy + ny);
	var secondCornerBad = !isWallCallback(this._endX + dx - nx, this._endY + dy - ny);
	this._endsWithAWall = isWallCallback(this._endX + dx, this._endY + dy);
	if ((firstCornerBad || secondCornerBad) && this._endsWithAWall) { return false; }

	return true;
}

/**
 * @param {function} digCallback Dig callback with a signature (x, y, value). Values: 0 = empty.
 */
ROT.Map.Feature.Corridor.prototype.create = function(digCallback) { 
	var sx = this._startX;
	var sy = this._startY;
	var dx = this._endX-sx;
	var dy = this._endY-sy;
	var length = 1+Math.max(Math.abs(dx), Math.abs(dy));
	
	if (dx) { dx = dx/Math.abs(dx); }
	if (dy) { dy = dy/Math.abs(dy); }
	var nx = dy;
	var ny = -dx;
	
	for (var i=0; i<length; i++) {
		var x = sx + i*dx;
		var y = sy + i*dy;
		digCallback(x, y, 0);
	}
	
	return true;
}

ROT.Map.Feature.Corridor.prototype.createPriorityWalls = function(priorityWallCallback) {
	if (!this._endsWithAWall) { return; }

	var sx = this._startX;
	var sy = this._startY;

	var dx = this._endX-sx;
	var dy = this._endY-sy;
	if (dx) { dx = dx/Math.abs(dx); }
	if (dy) { dy = dy/Math.abs(dy); }
	var nx = dy;
	var ny = -dx;

	priorityWallCallback(this._endX + dx, this._endY + dy);
	priorityWallCallback(this._endX + nx, this._endY + ny);
	priorityWallCallback(this._endX - nx, this._endY - ny);
}/**
 * @class Base noise generator
 */
ROT.Noise = function() {
};

ROT.Noise.prototype.get = function(x, y) {}
/**
 * A simple 2d implementation of simplex noise by Ondrej Zara
 *
 * Based on a speed-improved simplex noise algorithm for 2D, 3D and 4D in Java.
 * Which is based on example code by Stefan Gustavson (stegu@itn.liu.se).
 * With Optimisations by Peter Eastman (peastman@drizzle.stanford.edu).
 * Better rank ordering method by Stefan Gustavson in 2012.
 */

/**
 * @class 2D simplex noise generator
 * @param {int} [gradients=256] Random gradients
 */
ROT.Noise.Simplex = function(gradients) {
	ROT.Noise.call(this);

	this._F2 = 0.5 * (Math.sqrt(3) - 1);
    this._G2 = (3 - Math.sqrt(3)) / 6;

	this._gradients = [
		[ 0, -1],
		[ 1, -1],
		[ 1,  0],
		[ 1,  1],
		[ 0,  1],
		[-1,  1],
		[-1,  0],
		[-1, -1]
	];

	var permutations = [];
	var count = gradients || 256;
	for (var i=0;i<count;i++) { permutations.push(i); }
	permutations = permutations.randomize();

	this._perms = [];
	this._indexes = [];

	for (var i=0;i<2*count;i++) {
		this._perms.push(permutations[i % count]);
		this._indexes.push(this._perms[i] % this._gradients.length);
	}

};
ROT.Noise.Simplex.extend(ROT.Noise);

ROT.Noise.Simplex.prototype.get = function(xin, yin) {
	var perms = this._perms;
	var indexes = this._indexes;
	var count = perms.length/2;
	var G2 = this._G2;

	var n0 =0, n1 = 0, n2 = 0, gi; // Noise contributions from the three corners

	// Skew the input space to determine which simplex cell we're in
	var s = (xin + yin) * this._F2; // Hairy factor for 2D
	var i = Math.floor(xin + s);
	var j = Math.floor(yin + s);
	var t = (i + j) * G2;
	var X0 = i - t; // Unskew the cell origin back to (x,y) space
	var Y0 = j - t;
	var x0 = xin - X0; // The x,y distances from the cell origin
	var y0 = yin - Y0;

	// For the 2D case, the simplex shape is an equilateral triangle.
	// Determine which simplex we are in.
	var i1, j1; // Offsets for second (middle) corner of simplex in (i,j) coords
	if (x0 > y0) {
		i1 = 1;
		j1 = 0;
	} else { // lower triangle, XY order: (0,0)->(1,0)->(1,1)
		i1 = 0;
		j1 = 1;
	} // upper triangle, YX order: (0,0)->(0,1)->(1,1)

	// A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and
	// a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where
	// c = (3-sqrt(3))/6
	var x1 = x0 - i1 + G2; // Offsets for middle corner in (x,y) unskewed coords
	var y1 = y0 - j1 + G2;
	var x2 = x0 - 1 + 2*G2; // Offsets for last corner in (x,y) unskewed coords
	var y2 = y0 - 1 + 2*G2;

	// Work out the hashed gradient indices of the three simplex corners
	var ii = i.mod(count);
	var jj = j.mod(count);

	// Calculate the contribution from the three corners
	var t0 = 0.5 - x0*x0 - y0*y0;
	if (t0 >= 0) {
		t0 *= t0;
		gi = indexes[ii+perms[jj]];
		var grad = this._gradients[gi];
		n0 = t0 * t0 * (grad[0] * x0 + grad[1] * y0);
	}
	
	var t1 = 0.5 - x1*x1 - y1*y1;
	if (t1 >= 0) {
		t1 *= t1;
		gi = indexes[ii+i1+perms[jj+j1]];
		var grad = this._gradients[gi];
		n1 = t1 * t1 * (grad[0] * x1 + grad[1] * y1);
	}
	
	var t2 = 0.5 - x2*x2 - y2*y2;
	if (t2 >= 0) {
		t2 *= t2;
		gi = indexes[ii+1+perms[jj+1]];
		var grad = this._gradients[gi];
		n2 = t2 * t2 * (grad[0] * x2 + grad[1] * y2);
	}

	// Add contributions from each corner to get the final noise value.
	// The result is scaled to return values in the interval [-1,1].
	return 70 * (n0 + n1 + n2);
}
/**
 * @class Abstract FOV algorithm
 * @param {function} lightPassesCallback Does the light pass through x,y?
 * @param {object} [options]
 * @param {int} [options.topology=8] 4/6/8
 */
ROT.FOV = function(lightPassesCallback, options) {
	this._lightPasses = lightPassesCallback;
	this._options = {
		topology: 8
	}
	for (var p in options) { this._options[p] = options[p]; }
};

/**
 * Compute visibility for a 360-degree circle
 * @param {int} x
 * @param {int} y
 * @param {int} R Maximum visibility radius
 * @param {function} callback
 */
ROT.FOV.prototype.compute = function(x, y, R, callback) {}

/**
 * Return all neighbors in a concentric ring
 * @param {int} cx center-x
 * @param {int} cy center-y
 * @param {int} r range
 */
ROT.FOV.prototype._getCircle = function(cx, cy, r) {
	var result = [];
	var dirs, countFactor, startOffset;

	switch (this._options.topology) {
		case 4:
			countFactor = 1;
			startOffset = [0, 1];
			dirs = [
				ROT.DIRS[8][7],
				ROT.DIRS[8][1],
				ROT.DIRS[8][3],
				ROT.DIRS[8][5]
			]
		break;

		case 6:
			dirs = ROT.DIRS[6];
			countFactor = 1;
			startOffset = [-1, 1];
		break;

		case 8:
			dirs = ROT.DIRS[4];
			countFactor = 2;
			startOffset = [-1, 1];
		break;
	}

	/* starting neighbor */
	var x = cx + startOffset[0]*r;
	var y = cy + startOffset[1]*r;

	/* circle */
	for (var i=0;i<dirs.length;i++) {
		for (var j=0;j<r*countFactor;j++) {
			result.push([x, y]);
			x += dirs[i][0];
			y += dirs[i][1];

		}
	}

	return result;
}
/**
 * @class Discrete shadowcasting algorithm. Obsoleted by Precise shadowcasting.
 * @augments ROT.FOV
 */
ROT.FOV.DiscreteShadowcasting = function(lightPassesCallback, options) {
	ROT.FOV.call(this, lightPassesCallback, options);
}
ROT.FOV.DiscreteShadowcasting.extend(ROT.FOV);

/**
 * @see ROT.FOV#compute
 */
ROT.FOV.DiscreteShadowcasting.prototype.compute = function(x, y, R, callback) {
	var center = this._coords;
	var map = this._map;

	/* this place is always visible */
	callback(x, y, 0);

	/* standing in a dark place. FIXME is this a good idea?  */
	if (!this._lightPasses(x, y)) { return; }
	
	/* start and end angles */
	var DATA = [];
	
	var A, B, cx, cy, blocks;

	/* analyze surrounding cells in concentric rings, starting from the center */
	for (var r=1; r<=R; r++) {
		var neighbors = this._getCircle(x, y, r);
		var angle = 360 / neighbors.length;

		for (var i=0;i<neighbors.length;i++) {
			cx = neighbors[i][0];
			cy = neighbors[i][1];
			A = angle * (i - 0.5);
			B = A + angle;
			
			blocks = !this._lightPasses(cx, cy);
			if (this._visibleCoords(Math.floor(A), Math.ceil(B), blocks, DATA)) { callback(cx, cy, r, 1); }
			
			if (DATA.length == 2 && DATA[0] == 0 && DATA[1] == 360) { return; } /* cutoff? */

		} /* for all cells in this ring */
	} /* for all rings */
}

/**
 * @param {int} A start angle
 * @param {int} B end angle
 * @param {bool} blocks Does current cell block visibility?
 * @param {int[][]} DATA shadowed angle pairs
 */
ROT.FOV.DiscreteShadowcasting.prototype._visibleCoords = function(A, B, blocks, DATA) {
	if (A < 0) { 
		var v1 = arguments.callee(0, B, blocks, DATA);
		var v2 = arguments.callee(360+A, 360, blocks, DATA);
		return v1 || v2;
	}
	
	var index = 0;
	while (index < DATA.length && DATA[index] < A) { index++; }
	
	if (index == DATA.length) { /* completely new shadow */
		if (blocks) { DATA.push(A, B); } 
		return true;
	}
	
	var count = 0;
	
	if (index % 2) { /* this shadow starts in an existing shadow, or within its ending boundary */
		while (index < DATA.length && DATA[index] < B) {
			index++;
			count++;
		}
		
		if (count == 0) { return false; }
		
		if (blocks) { 
			if (count % 2) {
				DATA.splice(index-count, count, B);
			} else {
				DATA.splice(index-count, count);
			}
		}
		
		return true;

	} else { /* this shadow starts outside an existing shadow, or within a starting boundary */
		while (index < DATA.length && DATA[index] < B) {
			index++;
			count++;
		}
		
		/* visible when outside an existing shadow, or when overlapping */
		if (A == DATA[index-count] && count == 1) { return false; }
		
		if (blocks) { 
			if (count % 2) {
				DATA.splice(index-count, count, A);
			} else {
				DATA.splice(index-count, count, A, B);
			}
		}
			
		return true;
	}
}
/**
 * @class Precise shadowcasting algorithm
 * @augments ROT.FOV
 */
ROT.FOV.PreciseShadowcasting = function(lightPassesCallback, options) {
	ROT.FOV.call(this, lightPassesCallback, options);
}
ROT.FOV.PreciseShadowcasting.extend(ROT.FOV);

/**
 * @see ROT.FOV#compute
 */
ROT.FOV.PreciseShadowcasting.prototype.compute = function(x, y, R, callback) {
	/* this place is always visible */
	callback(x, y, 0, 1);

	/* standing in a dark place. FIXME is this a good idea?  */
	if (!this._lightPasses(x, y)) { return; }
	
	/* list of all shadows */
	var SHADOWS = [];
	
	var cx, cy, blocks, A1, A2, visibility;

	/* analyze surrounding cells in concentric rings, starting from the center */
	for (var r=1; r<=R; r++) {
		var neighbors = this._getCircle(x, y, r);
		var neighborCount = neighbors.length;

		for (var i=0;i<neighborCount;i++) {
			cx = neighbors[i][0];
			cy = neighbors[i][1];
			/* shift half-an-angle backwards to maintain consistency of 0-th cells */
			A1 = [i ? 2*i-1 : 2*neighborCount-1, 2*neighborCount];
			A2 = [2*i+1, 2*neighborCount]; 
			
			blocks = !this._lightPasses(cx, cy);
			visibility = this._checkVisibility(A1, A2, blocks, SHADOWS);
			if (visibility) { callback(cx, cy, r, visibility); }

			if (SHADOWS.length == 2 && SHADOWS[0][0] == 0 && SHADOWS[1][0] == SHADOWS[1][1]) { return; } /* cutoff? */

		} /* for all cells in this ring */
	} /* for all rings */
}

/**
 * @param {int[2]} A1 arc start
 * @param {int[2]} A2 arc end
 * @param {bool} blocks Does current arc block visibility?
 * @param {int[][]} SHADOWS list of active shadows
 */
ROT.FOV.PreciseShadowcasting.prototype._checkVisibility = function(A1, A2, blocks, SHADOWS) {
	if (A1[0] > A2[0]) { /* split into two sub-arcs */
		var v1 = this._checkVisibility(A1, [A1[1], A1[1]], blocks, SHADOWS);
		var v2 = this._checkVisibility([0, 1], A2, blocks, SHADOWS);
		return (v1+v2)/2;
	}

	/* index1: first shadow >= A1 */
	var index1 = 0, edge1 = false;
	while (index1 < SHADOWS.length) {
		var old = SHADOWS[index1];
		var diff = old[0]*A1[1] - A1[0]*old[1];
		if (diff >= 0) { /* old >= A1 */
			if (diff == 0 && !(index1 % 2)) { edge1 = true; }
			break;
		}
		index1++;
	}

	/* index2: last shadow <= A2 */
	var index2 = SHADOWS.length, edge2 = false;
	while (index2--) {
		var old = SHADOWS[index2];
		var diff = A2[0]*old[1] - old[0]*A2[1];
		if (diff >= 0) { /* old <= A2 */
			if (diff == 0 && (index2 % 2)) { edge2 = true; }
			break;
		}
	}

	var visible = true;
	if (index1 == index2 && (edge1 || edge2)) {  /* subset of existing shadow, one of the edges match */
		visible = false; 
	} else if (edge1 && edge2 && index1+1==index2 && (index2 % 2)) { /* completely equivalent with existing shadow */
		visible = false;
	} else if (index1 > index2 && (index1 % 2)) { /* subset of existing shadow, not touching */
		visible = false;
	}
	
	if (!visible) { return 0; } /* fast case: not visible */
	
	var visibleLength, P;

	/* compute the length of visible arc, adjust list of shadows (if blocking) */
	var remove = index2-index1+1;
	if (remove % 2) {
		if (index1 % 2) { /* first edge within existing shadow, second outside */
			var P = SHADOWS[index1];
			visibleLength = (A2[0]*P[1] - P[0]*A2[1]) / (P[1] * A2[1]);
			if (blocks) { SHADOWS.splice(index1, remove, A2); }
		} else { /* second edge within existing shadow, first outside */
			var P = SHADOWS[index2];
			visibleLength = (P[0]*A1[1] - A1[0]*P[1]) / (A1[1] * P[1]);
			if (blocks) { SHADOWS.splice(index1, remove, A1); }
		}
	} else {
		if (index1 % 2) { /* both edges within existing shadows */
			var P1 = SHADOWS[index1];
			var P2 = SHADOWS[index2];
			visibleLength = (P2[0]*P1[1] - P1[0]*P2[1]) / (P1[1] * P2[1]);
			if (blocks) { SHADOWS.splice(index1, remove); }
		} else { /* both edges outside existing shadows */
			if (blocks) { SHADOWS.splice(index1, remove, A1, A2); }
			return 1; /* whole arc visible! */
		}
	}

	var arcLength = (A2[0]*A1[1] - A1[0]*A2[1]) / (A1[1] * A2[1]);

	return visibleLength/arcLength;
}
/**
 * @class Recursive shadowcasting algorithm
 * Currently only supports 4/8 topologies, not hexagonal.
 * Based on Peter Harkins' implementation of Björn Bergström's algorithm described here: http://www.roguebasin.com/index.php?title=FOV_using_recursive_shadowcasting
 * @augments ROT.FOV
 */
ROT.FOV.RecursiveShadowcasting = function(lightPassesCallback, options) {
	ROT.FOV.call(this, lightPassesCallback, options);
}
ROT.FOV.RecursiveShadowcasting.extend(ROT.FOV);

/** Octants used for translating recursive shadowcasting offsets */
ROT.FOV.RecursiveShadowcasting.OCTANTS = [
	[-1,  0,  0,  1],
	[ 0, -1,  1,  0],
	[ 0, -1, -1,  0],
	[-1,  0,  0, -1],
	[ 1,  0,  0, -1],
	[ 0,  1, -1,  0],
	[ 0,  1,  1,  0],
	[ 1,  0,  0,  1]
];

/**
 * Compute visibility for a 360-degree circle
 * @param {int} x
 * @param {int} y
 * @param {int} R Maximum visibility radius
 * @param {function} callback
 */
ROT.FOV.RecursiveShadowcasting.prototype.compute = function(x, y, R, callback) {
	//You can always see your own tile
	callback(x, y, 0, true);
	for(var i = 0; i < ROT.FOV.RecursiveShadowcasting.OCTANTS.length; i++) {
		this._renderOctant(x, y, ROT.FOV.RecursiveShadowcasting.OCTANTS[i], R, callback);
	}
}

/**
 * Compute visibility for a 180-degree arc
 * @param {int} x
 * @param {int} y
 * @param {int} R Maximum visibility radius
 * @param {int} dir Direction to look in (expressed in a ROT.DIR value);
 * @param {function} callback
 */
ROT.FOV.RecursiveShadowcasting.prototype.compute180 = function(x, y, R, dir, callback) {
	//You can always see your own tile
	callback(x, y, 0, true);
	var previousOctant = (dir - 1 + 8) % 8; //Need to retrieve the previous octant to render a full 180 degrees
	var nextPreviousOctant = (dir - 2 + 8) % 8; //Need to retrieve the previous two octants to render a full 180 degrees
	var nextOctant = (dir+ 1 + 8) % 8; //Need to grab to next octant to render a full 180 degrees
	this._renderOctant(x, y, ROT.FOV.RecursiveShadowcasting.OCTANTS[nextPreviousOctant], R, callback);
	this._renderOctant(x, y, ROT.FOV.RecursiveShadowcasting.OCTANTS[previousOctant], R, callback);
	this._renderOctant(x, y, ROT.FOV.RecursiveShadowcasting.OCTANTS[dir], R, callback);
	this._renderOctant(x, y, ROT.FOV.RecursiveShadowcasting.OCTANTS[nextOctant], R, callback);
}

/**
 * Compute visibility for a 90-degree arc
 * @param {int} x
 * @param {int} y
 * @param {int} R Maximum visibility radius
 * @param {int} dir Direction to look in (expressed in a ROT.DIR value);
 * @param {function} callback
 */
ROT.FOV.RecursiveShadowcasting.prototype.compute90 = function(x, y, R, dir, callback) {
	//You can always see your own tile
	callback(x, y, 0, true);
	var previousOctant = (dir - 1 + 8) % 8; //Need to retrieve the previous octant to render a full 90 degrees
	this._renderOctant(x, y, ROT.FOV.RecursiveShadowcasting.OCTANTS[dir], R, callback);
	this._renderOctant(x, y, ROT.FOV.RecursiveShadowcasting.OCTANTS[previousOctant], R, callback);
}

/**
 * Render one octant (45-degree arc) of the viewshed
 * @param {int} x
 * @param {int} y
 * @param {int} octant Octant to be rendered
 * @param {int} R Maximum visibility radius
 * @param {function} callback
 */
ROT.FOV.RecursiveShadowcasting.prototype._renderOctant = function(x, y, octant, R, callback) {
	//Radius incremented by 1 to provide same coverage area as other shadowcasting radiuses
	this._castVisibility(x, y, 1, 1.0, 0.0, R + 1, octant[0], octant[1], octant[2], octant[3], callback);
}

/**
 * Actually calculates the visibility
 * @param {int} startX The starting X coordinate
 * @param {int} startY The starting Y coordinate
 * @param {int} row The row to render
 * @param {float} visSlopeStart The slope to start at
 * @param {float} visSlopeEnd The slope to end at
 * @param {int} radius The radius to reach out to
 * @param {int} xx 
 * @param {int} xy 
 * @param {int} yx 
 * @param {int} yy 
 * @param {function} callback The callback to use when we hit a block that is visible
 */
ROT.FOV.RecursiveShadowcasting.prototype._castVisibility = function(startX, startY, row, visSlopeStart, visSlopeEnd, radius, xx, xy, yx, yy, callback) {
	if(visSlopeStart < visSlopeEnd) { return; }
	for(var i = row; i <= radius; i++) {
		var dx = -i - 1;
		var dy = -i;
		var blocked = false;
		var newStart = 0;

		//'Row' could be column, names here assume octant 0 and would be flipped for half the octants
		while(dx <= 0) {
			dx += 1;

			//Translate from relative coordinates to map coordinates
			var mapX = startX + dx * xx + dy * xy;
			var mapY = startY + dx * yx + dy * yy;

			//Range of the row
			var slopeStart = (dx - 0.5) / (dy + 0.5);
			var slopeEnd = (dx + 0.5) / (dy - 0.5);
		
			//Ignore if not yet at left edge of Octant
			if(slopeEnd > visSlopeStart) { continue; }
			
			//Done if past right edge
			if(slopeStart < visSlopeEnd) { break; }
				
			//If it's in range, it's visible
			if((dx * dx + dy * dy) < (radius * radius)) {
				callback(mapX, mapY, i, true);
			}
	
			if(!blocked) {
				//If tile is a blocking tile, cast around it
				if(!this._lightPasses(mapX, mapY) && i < radius) {
					blocked = true;
					this._castVisibility(startX, startY, i + 1, visSlopeStart, slopeStart, radius, xx, xy, yx, yy, callback);
					newStart = slopeEnd;
				}
			} else {
				//Keep narrowing if scanning across a block
				if(!this._lightPasses(mapX, mapY)) {
					newStart = slopeEnd;
					continue;
				}
			
				//Block has ended
				blocked = false;
				visSlopeStart = newStart;
			}
		}
		if(blocked) { break; }
	}
}
/**
 * @namespace Color operations
 */
ROT.Color = {
	fromString: function(str) {
		var cached, r;
		if (str in this._cache) {
			cached = this._cache[str];
		} else {
			if (str.charAt(0) == "#") { /* hex rgb */

				var values = str.match(/[0-9a-f]/gi).map(function(x) { return parseInt(x, 16); });
				if (values.length == 3) {
					cached = values.map(function(x) { return x*17; });
				} else {
					for (var i=0;i<3;i++) {
						values[i+1] += 16*values[i];
						values.splice(i, 1);
					}
					cached = values;
				}

			} else if (r = str.match(/rgb\(([0-9, ]+)\)/i)) { /* decimal rgb */
				cached = r[1].split(/\s*,\s*/).map(function(x) { return parseInt(x); });
			} else { /* html name */
				cached = [0, 0, 0];
			}

			this._cache[str] = cached;
		}

		return cached.slice();
	},

	/**
	 * Add two or more colors
	 * @param {number[]} color1
	 * @param {number[]} color2
	 * @returns {number[]}
	 */
	add: function(color1, color2) {
		var result = color1.slice();
		for (var i=0;i<3;i++) {
			for (var j=1;j<arguments.length;j++) {
				result[i] += arguments[j][i];
			}
		}
		return result;
	},

	/**
	 * Add two or more colors, MODIFIES FIRST ARGUMENT
	 * @param {number[]} color1
	 * @param {number[]} color2
	 * @returns {number[]}
	 */
	add_: function(color1, color2) {
		for (var i=0;i<3;i++) {
			for (var j=1;j<arguments.length;j++) {
				color1[i] += arguments[j][i];
			}
		}
		return color1;
	},

	/**
	 * Multiply (mix) two or more colors
	 * @param {number[]} color1
	 * @param {number[]} color2
	 * @returns {number[]}
	 */
	multiply: function(color1, color2) {
		var result = color1.slice();
		for (var i=0;i<3;i++) {
			for (var j=1;j<arguments.length;j++) {
				result[i] *= arguments[j][i] / 255;
			}
			result[i] = Math.round(result[i]);
		}
		return result;
	},

	/**
	 * Multiply (mix) two or more colors, MODIFIES FIRST ARGUMENT
	 * @param {number[]} color1
	 * @param {number[]} color2
	 * @returns {number[]}
	 */
	multiply_: function(color1, color2) {
		for (var i=0;i<3;i++) {
			for (var j=1;j<arguments.length;j++) {
				color1[i] *= arguments[j][i] / 255;
			}
			color1[i] = Math.round(color1[i]);
		}
		return color1;
	},

	/**
	 * Interpolate (blend) two colors with a given factor
	 * @param {number[]} color1
	 * @param {number[]} color2
	 * @param {float} [factor=0.5] 0..1
	 * @returns {number[]}
	 */
	interpolate: function(color1, color2, factor) {
		if (arguments.length < 3) { factor = 0.5; }
		var result = color1.slice();
		for (var i=0;i<3;i++) {
			result[i] = Math.round(result[i] + factor*(color2[i]-color1[i]));
		}
		return result;
	},

	/**
	 * Interpolate (blend) two colors with a given factor in HSL mode
	 * @param {number[]} color1
	 * @param {number[]} color2
	 * @param {float} [factor=0.5] 0..1
	 * @returns {number[]}
	 */
	interpolateHSL: function(color1, color2, factor) {
		if (arguments.length < 3) { factor = 0.5; }
		var hsl1 = this.rgb2hsl(color1);
		var hsl2 = this.rgb2hsl(color2);
		for (var i=0;i<3;i++) {
			hsl1[i] += factor*(hsl2[i]-hsl1[i]);
		}
		return this.hsl2rgb(hsl1);
	},

	/**
	 * Create a new random color based on this one
	 * @param {number[]} color
	 * @param {number[]} diff Set of standard deviations
	 * @returns {number[]}
	 */
	randomize: function(color, diff) {
		if (!(diff instanceof Array)) { diff = ROT.RNG.getNormal(0, diff); }
		var result = color.slice();
		for (var i=0;i<3;i++) {
			result[i] += (diff instanceof Array ? Math.round(ROT.RNG.getNormal(0, diff[i])) : diff);
		}
		return result;
	},

	/**
	 * Converts an RGB color value to HSL. Expects 0..255 inputs, produces 0..1 outputs.
	 * @param {number[]} color
	 * @returns {number[]}
	 */
	rgb2hsl: function(color) {
		var r = color[0]/255;
		var g = color[1]/255;
		var b = color[2]/255;

		var max = Math.max(r, g, b), min = Math.min(r, g, b);
		var h, s, l = (max + min) / 2;

		if (max == min) {
			h = s = 0; // achromatic
		} else {
			var d = max - min;
			s = (l > 0.5 ? d / (2 - max - min) : d / (max + min));
			switch(max) {
				case r: h = (g - b) / d + (g < b ? 6 : 0); break;
				case g: h = (b - r) / d + 2; break;
				case b: h = (r - g) / d + 4; break;
			}
			h /= 6;
		}

		return [h, s, l];
	},

	/**
	 * Converts an HSL color value to RGB. Expects 0..1 inputs, produces 0..255 outputs.
	 * @param {number[]} color
	 * @returns {number[]}
	 */
	hsl2rgb: function(color) {
		var l = color[2];

		if (color[1] == 0) {
			l = Math.round(l*255);
			return [l, l, l];
		} else {
			function hue2rgb(p, q, t) {
				if (t < 0) t += 1;
				if (t > 1) t -= 1;
				if (t < 1/6) return p + (q - p) * 6 * t;
				if (t < 1/2) return q;
				if (t < 2/3) return p + (q - p) * (2/3 - t) * 6;
				return p;
			}

			var s = color[1];
			var q = (l < 0.5 ? l * (1 + s) : l + s - l * s);
			var p = 2 * l - q;
			var r = hue2rgb(p, q, color[0] + 1/3);
			var g = hue2rgb(p, q, color[0]);
			var b = hue2rgb(p, q, color[0] - 1/3);
			return [Math.round(r*255), Math.round(g*255), Math.round(b*255)];
		}
	},

	toRGB: function(color) {
		return "rgb(" + this._clamp(color[0]) + "," + this._clamp(color[1]) + "," + this._clamp(color[2]) + ")";
	},

	toHex: function(color) {
		var parts = [];
		for (var i=0;i<3;i++) {
			parts.push(this._clamp(color[i]).toString(16).lpad("0", 2));
		}
		return "#" + parts.join("");
	},

	_clamp: function(num) {
		if (num < 0) {
			return 0;
		} else if (num > 255) {
			return 255;
		} else {
			return num;
		}
	},

	_cache: {
		"black": [0,0,0],
		"navy": [0,0,128],
		"darkblue": [0,0,139],
		"mediumblue": [0,0,205],
		"blue": [0,0,255],
		"darkgreen": [0,100,0],
		"green": [0,128,0],
		"teal": [0,128,128],
		"darkcyan": [0,139,139],
		"deepskyblue": [0,191,255],
		"darkturquoise": [0,206,209],
		"mediumspringgreen": [0,250,154],
		"lime": [0,255,0],
		"springgreen": [0,255,127],
		"aqua": [0,255,255],
		"cyan": [0,255,255],
		"midnightblue": [25,25,112],
		"dodgerblue": [30,144,255],
		"forestgreen": [34,139,34],
		"seagreen": [46,139,87],
		"darkslategray": [47,79,79],
		"darkslategrey": [47,79,79],
		"limegreen": [50,205,50],
		"mediumseagreen": [60,179,113],
		"turquoise": [64,224,208],
		"royalblue": [65,105,225],
		"steelblue": [70,130,180],
		"darkslateblue": [72,61,139],
		"mediumturquoise": [72,209,204],
		"indigo": [75,0,130],
		"darkolivegreen": [85,107,47],
		"cadetblue": [95,158,160],
		"cornflowerblue": [100,149,237],
		"mediumaquamarine": [102,205,170],
		"dimgray": [105,105,105],
		"dimgrey": [105,105,105],
		"slateblue": [106,90,205],
		"olivedrab": [107,142,35],
		"slategray": [112,128,144],
		"slategrey": [112,128,144],
		"lightslategray": [119,136,153],
		"lightslategrey": [119,136,153],
		"mediumslateblue": [123,104,238],
		"lawngreen": [124,252,0],
		"chartreuse": [127,255,0],
		"aquamarine": [127,255,212],
		"maroon": [128,0,0],
		"purple": [128,0,128],
		"olive": [128,128,0],
		"gray": [128,128,128],
		"grey": [128,128,128],
		"skyblue": [135,206,235],
		"lightskyblue": [135,206,250],
		"blueviolet": [138,43,226],
		"darkred": [139,0,0],
		"darkmagenta": [139,0,139],
		"saddlebrown": [139,69,19],
		"darkseagreen": [143,188,143],
		"lightgreen": [144,238,144],
		"mediumpurple": [147,112,216],
		"darkviolet": [148,0,211],
		"palegreen": [152,251,152],
		"darkorchid": [153,50,204],
		"yellowgreen": [154,205,50],
		"sienna": [160,82,45],
		"brown": [165,42,42],
		"darkgray": [169,169,169],
		"darkgrey": [169,169,169],
		"lightblue": [173,216,230],
		"greenyellow": [173,255,47],
		"paleturquoise": [175,238,238],
		"lightsteelblue": [176,196,222],
		"powderblue": [176,224,230],
		"firebrick": [178,34,34],
		"darkgoldenrod": [184,134,11],
		"mediumorchid": [186,85,211],
		"rosybrown": [188,143,143],
		"darkkhaki": [189,183,107],
		"silver": [192,192,192],
		"mediumvioletred": [199,21,133],
		"indianred": [205,92,92],
		"peru": [205,133,63],
		"chocolate": [210,105,30],
		"tan": [210,180,140],
		"lightgray": [211,211,211],
		"lightgrey": [211,211,211],
		"palevioletred": [216,112,147],
		"thistle": [216,191,216],
		"orchid": [218,112,214],
		"goldenrod": [218,165,32],
		"crimson": [220,20,60],
		"gainsboro": [220,220,220],
		"plum": [221,160,221],
		"burlywood": [222,184,135],
		"lightcyan": [224,255,255],
		"lavender": [230,230,250],
		"darksalmon": [233,150,122],
		"violet": [238,130,238],
		"palegoldenrod": [238,232,170],
		"lightcoral": [240,128,128],
		"khaki": [240,230,140],
		"aliceblue": [240,248,255],
		"honeydew": [240,255,240],
		"azure": [240,255,255],
		"sandybrown": [244,164,96],
		"wheat": [245,222,179],
		"beige": [245,245,220],
		"whitesmoke": [245,245,245],
		"mintcream": [245,255,250],
		"ghostwhite": [248,248,255],
		"salmon": [250,128,114],
		"antiquewhite": [250,235,215],
		"linen": [250,240,230],
		"lightgoldenrodyellow": [250,250,210],
		"oldlace": [253,245,230],
		"red": [255,0,0],
		"fuchsia": [255,0,255],
		"magenta": [255,0,255],
		"deeppink": [255,20,147],
		"orangered": [255,69,0],
		"tomato": [255,99,71],
		"hotpink": [255,105,180],
		"coral": [255,127,80],
		"darkorange": [255,140,0],
		"lightsalmon": [255,160,122],
		"orange": [255,165,0],
		"lightpink": [255,182,193],
		"pink": [255,192,203],
		"gold": [255,215,0],
		"peachpuff": [255,218,185],
		"navajowhite": [255,222,173],
		"moccasin": [255,228,181],
		"bisque": [255,228,196],
		"mistyrose": [255,228,225],
		"blanchedalmond": [255,235,205],
		"papayawhip": [255,239,213],
		"lavenderblush": [255,240,245],
		"seashell": [255,245,238],
		"cornsilk": [255,248,220],
		"lemonchiffon": [255,250,205],
		"floralwhite": [255,250,240],
		"snow": [255,250,250],
		"yellow": [255,255,0],
		"lightyellow": [255,255,224],
		"ivory": [255,255,240],
		"white": [255,255,255]
	}
}
/**
 * @class Lighting computation, based on a traditional FOV for multiple light sources and multiple passes.
 * @param {function} reflectivityCallback Callback to retrieve cell reflectivity (0..1)
 * @param {object} [options]
 * @param {int} [options.passes=1] Number of passes. 1 equals to simple FOV of all light sources, >1 means a *highly simplified* radiosity-like algorithm.
 * @param {int} [options.emissionThreshold=100] Cells with emissivity > threshold will be treated as light source in the next pass.
 * @param {int} [options.range=10] Max light range
 */
ROT.Lighting = function(reflectivityCallback, options) {
	this._reflectivityCallback = reflectivityCallback;
	this._options = {
		passes: 1,
		emissionThreshold: 100,
		range: 10
	};
	this._fov = null;

	this._lights = {};
	this._reflectivityCache = {};
	this._fovCache = {};

	this.setOptions(options);
}

/**
 * Adjust options at runtime
 * @see ROT.Lighting
 * @param {object} [options]
 */
ROT.Lighting.prototype.setOptions = function(options) {
	for (var p in options) { this._options[p] = options[p]; }
	if (options.range) { this.reset(); }
	return this;
}

/**
 * Set the used Field-Of-View algo
 * @param {ROT.FOV} fov
 */
ROT.Lighting.prototype.setFOV = function(fov) {
	this._fov = fov;
	this._fovCache = {};
	return this;
}

/**
 * Set (or remove) a light source
 * @param {int} x
 * @param {int} y
 * @param {null || string || number[3]} color
 */
ROT.Lighting.prototype.setLight = function(x, y, color) {
	var key = x+","+y;

	if (color) {
		this._lights[key] = (typeof(color) == "string" ? ROT.Color.fromString(color) : color);
	} else {
		delete this._lights[key];
	}
	return this;
}

/**
 * Reset the pre-computed topology values. Call whenever the underlying map changes its light-passability.
 */
ROT.Lighting.prototype.reset = function() {
	this._reflectivityCache = {};
	this._fovCache = {};

	return this;
}

/**
 * Compute the lighting
 * @param {function} lightingCallback Will be called with (x, y, color) for every lit cell
 */
ROT.Lighting.prototype.compute = function(lightingCallback) {
	var doneCells = {};
	var emittingCells = {};
	var litCells = {};

	for (var key in this._lights) { /* prepare emitters for first pass */
		var light = this._lights[key];
		if (!(key in emittingCells)) { emittingCells[key] = [0, 0, 0]; }

		ROT.Color.add_(emittingCells[key], light);
	}

	for (var i=0;i<this._options.passes;i++) { /* main loop */
		this._emitLight(emittingCells, litCells, doneCells);
		if (i+1 == this._options.passes) { continue; } /* not for the last pass */
		emittingCells = this._computeEmitters(litCells, doneCells);
	}

	for (var litKey in litCells) { /* let the user know what and how is lit */
		var parts = litKey.split(",");
		var x = parseInt(parts[0]);
		var y = parseInt(parts[1]);
		lightingCallback(x, y, litCells[litKey]);
	}

	return this;
}

/**
 * Compute one iteration from all emitting cells
 * @param {object} emittingCells These emit light
 * @param {object} litCells Add projected light to these
 * @param {object} doneCells These already emitted, forbid them from further calculations
 */
ROT.Lighting.prototype._emitLight = function(emittingCells, litCells, doneCells) {
	for (var key in emittingCells) {
		var parts = key.split(",");
		var x = parseInt(parts[0]);
		var y = parseInt(parts[1]);
		this._emitLightFromCell(x, y, emittingCells[key], litCells);
		doneCells[key] = 1;
	}
	return this;
}

/**
 * Prepare a list of emitters for next pass
 * @param {object} litCells
 * @param {object} doneCells
 * @returns {object}
 */
ROT.Lighting.prototype._computeEmitters = function(litCells, doneCells) {
	var result = {};

	for (var key in litCells) {
		if (key in doneCells) { continue; } /* already emitted */

		var color = litCells[key];

		if (key in this._reflectivityCache) {
			var reflectivity = this._reflectivityCache[key];
		} else {
			var parts = key.split(",");
			var x = parseInt(parts[0]);
			var y = parseInt(parts[1]);
			var reflectivity = this._reflectivityCallback(x, y);
			this._reflectivityCache[key] = reflectivity;
		}

		if (reflectivity == 0) { continue; } /* will not reflect at all */

		/* compute emission color */
		var emission = [];
		var intensity = 0;
		for (var i=0;i<3;i++) {
			var part = Math.round(color[i]*reflectivity);
			emission[i] = part;
			intensity += part;
		}
		if (intensity > this._options.emissionThreshold) { result[key] = emission; }
	}

	return result;
}

/**
 * Compute one iteration from one cell
 * @param {int} x
 * @param {int} y
 * @param {number[]} color
 * @param {object} litCells Cell data to by updated
 */
ROT.Lighting.prototype._emitLightFromCell = function(x, y, color, litCells) {
	var key = x+","+y;
	if (key in this._fovCache) {
		var fov = this._fovCache[key];
	} else {
		var fov = this._updateFOV(x, y);
	}

	for (var fovKey in fov) {
		var formFactor = fov[fovKey];

		if (fovKey in litCells) { /* already lit */
			var result = litCells[fovKey];
		} else { /* newly lit */
			var result = [0, 0, 0];
			litCells[fovKey] = result;
		}

		for (var i=0;i<3;i++) { result[i] += Math.round(color[i]*formFactor); } /* add light color */
	}

	return this;
}

/**
 * Compute FOV ("form factor") for a potential light source at [x,y]
 * @param {int} x
 * @param {int} y
 * @returns {object}
 */
ROT.Lighting.prototype._updateFOV = function(x, y) {
	var key1 = x+","+y;
	var cache = {};
	this._fovCache[key1] = cache;
	var range = this._options.range;
	var cb = function(x, y, r, vis) {
		var key2 = x+","+y;
		var formFactor = vis * (1-r/range);
		if (formFactor == 0) { return; }
		cache[key2] = formFactor;
	}
	this._fov.compute(x, y, range, cb.bind(this));

	return cache;
}
/**
 * @class Abstract pathfinder
 * @param {int} toX Target X coord
 * @param {int} toY Target Y coord
 * @param {function} passableCallback Callback to determine map passability
 * @param {object} [options]
 * @param {int} [options.topology=8]
 */
ROT.Path = function(toX, toY, passableCallback, options) {
	this._toX = toX;
	this._toY = toY;
	this._fromX = null;
	this._fromY = null;
	this._passableCallback = passableCallback;
	this._options = {
		topology: 8
	}
	for (var p in options) { this._options[p] = options[p]; }

	this._dirs = ROT.DIRS[this._options.topology];
	if (this._options.topology == 8) { /* reorder dirs for more aesthetic result (vertical/horizontal first) */
		this._dirs = [
			this._dirs[0],
			this._dirs[2],
			this._dirs[4],
			this._dirs[6],
			this._dirs[1],
			this._dirs[3],
			this._dirs[5],
			this._dirs[7]
		]
	}
}

/**
 * Compute a path from a given point
 * @param {int} fromX
 * @param {int} fromY
 * @param {function} callback Will be called for every path item with arguments "x" and "y"
 */
ROT.Path.prototype.compute = function(fromX, fromY, callback) {
}

ROT.Path.prototype._getNeighbors = function(cx, cy) {
	var result = [];
	for (var i=0;i<this._dirs.length;i++) {
		var dir = this._dirs[i];
		var x = cx + dir[0];
		var y = cy + dir[1];
		
		if (!this._passableCallback(x, y)) { continue; }
		result.push([x, y]);
	}
	
	return result;
}
/**
 * @class Simplified Dijkstra's algorithm: all edges have a value of 1
 * @augments ROT.Path
 * @see ROT.Path
 */
ROT.Path.Dijkstra = function(toX, toY, passableCallback, options) {
	ROT.Path.call(this, toX, toY, passableCallback, options);

	this._computed = {};
	this._todo = [];
	this._add(toX, toY, null);
}
ROT.Path.Dijkstra.extend(ROT.Path);

/**
 * Compute a path from a given point
 * @see ROT.Path#compute
 */
ROT.Path.Dijkstra.prototype.compute = function(fromX, fromY, callback) {
	var key = fromX+","+fromY;
	if (!(key in this._computed)) { this._compute(fromX, fromY); }
	if (!(key in this._computed)) { return; }
	
	var item = this._computed[key];
	while (item) {
		callback(item.x, item.y);
		item = item.prev;
	}
}

/**
 * Compute a non-cached value
 */
ROT.Path.Dijkstra.prototype._compute = function(fromX, fromY) {
	while (this._todo.length) {
		var item = this._todo.shift();
		if (item.x == fromX && item.y == fromY) { return; }
		
		var neighbors = this._getNeighbors(item.x, item.y);
		
		for (var i=0;i<neighbors.length;i++) {
			var neighbor = neighbors[i];
			var x = neighbor[0];
			var y = neighbor[1];
			var id = x+","+y;
			if (id in this._computed) { continue; } /* already done */	
			this._add(x, y, item); 
		}
	}
}

ROT.Path.Dijkstra.prototype._add = function(x, y, prev) {
	var obj = {
		x: x,
		y: y,
		prev: prev
	}
	this._computed[x+","+y] = obj;
	this._todo.push(obj);
}
/**
 * @class Simplified A* algorithm: all edges have a value of 1
 * @augments ROT.Path
 * @see ROT.Path
 */
ROT.Path.AStar = function(toX, toY, passableCallback, options) {
	ROT.Path.call(this, toX, toY, passableCallback, options);

	this._todo = [];
	this._done = {};
	this._fromX = null;
	this._fromY = null;
}
ROT.Path.AStar.extend(ROT.Path);

/**
 * Compute a path from a given point
 * @see ROT.Path#compute
 */
ROT.Path.AStar.prototype.compute = function(fromX, fromY, callback) {
	this._todo = [];
	this._done = {};
	this._fromX = fromX;
	this._fromY = fromY;
	this._add(this._toX, this._toY, null);

	while (this._todo.length) {
		var item = this._todo.shift();
		if (item.x == fromX && item.y == fromY) { break; }
		var neighbors = this._getNeighbors(item.x, item.y);

		for (var i=0;i<neighbors.length;i++) {
			var neighbor = neighbors[i];
			var x = neighbor[0];
			var y = neighbor[1];
			var id = x+","+y;
			if (id in this._done) { continue; }
			this._add(x, y, item); 
		}
	}
	
	var item = this._done[fromX+","+fromY];
	if (!item) { return; }
	
	while (item) {
		callback(item.x, item.y);
		item = item.prev;
	}
}

ROT.Path.AStar.prototype._add = function(x, y, prev) {
	var obj = {
		x: x,
		y: y,
		prev: prev,
		g: (prev ? prev.g+1 : 0),
		h: this._distance(x, y)
	}
	this._done[x+","+y] = obj;
	
	/* insert into priority queue */
	
	var f = obj.g + obj.h;
	for (var i=0;i<this._todo.length;i++) {
		var item = this._todo[i];
		if (f < item.g + item.h) {
			this._todo.splice(i, 0, obj);
			return;
		}
	}
	
	this._todo.push(obj);
}

ROT.Path.AStar.prototype._distance = function(x, y) {
	switch (this._options.topology) {
		case 4:
			return (Math.abs(x-this._fromX) + Math.abs(y-this._fromY));
		break;

		case 6:
			var dx = Math.abs(x - this._fromX);
			var dy = Math.abs(y - this._fromY);
			return dy + Math.max(0, (dx-dy)/2);
		break;

		case 8: 
			return Math.max(Math.abs(x-this._fromX), Math.abs(y-this._fromY));
		break;
	}
}