Add the transitions module

Author: lukash

src/lib/transitions.c

@@ -0,0 +1,37 @@
+// Copyright 2025 Lukas Hrazky
+//
+// This file is part of the Refloat VESC package.
+//
+// Refloat VESC package is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by the
+// Free Software Foundation, either version 3 of the License, or (at your
+// option) any later version.
+//
+// Refloat VESC package is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+// more details.
+//
+// You should have received a copy of the GNU General Public License along with
+// this program. If not, see <http://www.gnu.org/licenses/>.
+
+#include "transitions.h"
+
+#define check_and_return(x)                                                                        \
+    do {                                                                                           \
+        if (x < 0.0f) {                                                                            \
+            return 0.0f;                                                                           \
+        } else if (x > 1.0f) {                                                                     \
+            return 1.0f;                                                                           \
+        }                                                                                          \
+    } while (0)
+
+float smoothstep(float x) {
+    check_and_return(x);
+    return x * x * (3.0f - 2.0f * x);
+}
+
+float smootherstep(float x) {
+    check_and_return(x);
+    return x * x * x * (x * (x * 6.0f - 15.0f) + 10.0f);
+}

src/lib/transitions.h

@@ -0,0 +1,22 @@
+// Copyright 2025 Lukas Hrazky
+//
+// This file is part of the Refloat VESC package.
+//
+// Refloat VESC package is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by the
+// Free Software Foundation, either version 3 of the License, or (at your
+// option) any later version.
+//
+// Refloat VESC package is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+// or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+// more details.
+//
+// You should have received a copy of the GNU General Public License along with
+// this program. If not, see <http://www.gnu.org/licenses/>.
+
+#pragma once
+
+float smoothstep(float x);
+
+float smootherstep(float x);