20250104

resources/shaders/common.glsl

@@ -185,6 +185,55 @@ vec3 darken(vec3 color, float fac) { return color * (1.0 - fac); }
 // color will be white.
 vec3 lighten(vec3 color, float fac) { return color + (vec3(1.0) - color) * fac; }
 
+
+//change the color based on an offset amount 
+vec3 offsetHue(vec3 color, float hueOffset) {
+    // Convert RGB to HSV
+    float maxC = max(max(color.r, color.g), color.b);
+    float minC = min(min(color.r, color.g), color.b);
+    float delta = maxC - minC;
+
+    float hue = 0.0;
+    if (delta > 0.0) {
+        if (maxC == color.r) {
+            hue = mod((color.g - color.b) / delta, 6.0);
+        } else if (maxC == color.g) {
+            hue = (color.b - color.r) / delta + 2.0;
+        } else {
+            hue = (color.r - color.g) / delta + 4.0;
+        }
+    }
+    hue /= 6.0;
+
+    float saturation = (maxC > 0.0) ? (delta / maxC) : 0.0;
+    float value = maxC;
+
+    // Offset the hue
+    hue = mod(hue + hueOffset, 1.0);
+
+    // Convert HSV back to RGB
+    float c = value * saturation;
+    float x = c * (1.0 - abs(mod(hue * 6.0, 2.0) - 1.0));
+    float m = value - c;
+
+    vec3 rgb;
+    if (hue < 1.0 / 6.0) {
+        rgb = vec3(c, x, 0.0);
+    } else if (hue < 2.0 / 6.0) {
+        rgb = vec3(x, c, 0.0);
+    } else if (hue < 3.0 / 6.0) {
+        rgb = vec3(0.0, c, x);
+    } else if (hue < 4.0 / 6.0) {
+        rgb = vec3(0.0, x, c);
+    } else if (hue < 5.0 / 6.0) {
+        rgb = vec3(x, 0.0, c);
+    } else {
+        rgb = vec3(c, 0.0, x);
+    }
+
+    return rgb + m;
+}
+
 // ---------------------------------------------------------------------- easing functions
 
 // Here are some basic easing function. More can be added if required!