Merge pull request #615 from njoubert/correct_color_blend

Lerping Color Correctly

Author: Lauren McCarthy

lib/p5.js

@@ -2100,20 +2100,21 @@ amdclean['colorcreating_reading'] = function (require, core, p5Color) {
     return c.getHue();
   };
   p5.prototype.lerpColor = function (c1, c2, amt) {
+    amt = Math.max(Math.min(amt, 1), 0);
     if (c1 instanceof Array) {
       var c = [];
       for (var i = 0; i < c1.length; i++) {
-        c.push(p5.prototype.lerp(c1[i], c2[i], amt));
+        c.push(Math.sqrt(p5.prototype.lerp(c1[i]*c1[i], c2[i]*c2[i], amt)));
       }
       return c;
     } else if (c1 instanceof p5.Color) {
       var pc = [];
       for (var j = 0; j < 4; j++) {
-        pc.push(p5.prototype.lerp(c1.rgba[j], c2.rgba[j], amt));
+        pc.push(Math.sqrt(p5.prototype.lerp(c1.rgba[j]*c1.rgba[j], c2.rgba[j]*c2.rgba[j], amt)));
       }
       return new p5.Color(this, pc);
     } else {
-      return p5.prototype.lerp(c1, c2, amt);
+      return Math.sqrt(p5.prototype.lerp(c1*c1, c2*c2, amt));
     }
   };
   p5.prototype.red = function (c) {