debugui: bug fix: pointingDelta should return (0, 0) for a new touch

hajimehoshi · hajimehoshi · commit 6097f763a053 · 2025-09-23T17:46:46.000+09:00
Closes #45
diff --git a/widget.go b/widget.go
@@ -63,6 +63,10 @@ func (c *Context) pointingOver(bounds image.Rectangle) bool {
 }
 
 func (c *Context) pointingDelta() image.Point {
+	// The delta is always (0, 0) when a touch just started.
+	if c.pointing.isTouchActive() && c.pointing.justPressed() {
+		return image.Point{}
+	}
 	return c.pointingPosition().Sub(c.lastPointingPos)
 }
 

Original file line number	Diff line number	Diff line change
`@@ -63,6 +63,10 @@ func (c *Context) pointingOver(bounds image.Rectangle) bool {`
`63`	`63`	`}`
`64`	`64`
`65`	`65`	`func (c *Context) pointingDelta() image.Point {`
	`66`	`+ // The delta is always (0, 0) when a touch just started.`
	`67`	`+ if c.pointing.isTouchActive() && c.pointing.justPressed() {`
	`68`	`+ return image.Point{}`
	`69`	`+ }`
`66`	`70`	`return c.pointingPosition().Sub(c.lastPointingPos)`
`67`	`71`	`}`
`68`	`72`