Remove DefaultPenAttributes

Author: adroitwhiz

src/PenSkin.js

@@ -12,18 +12,6 @@ const ShaderManager = require('./ShaderManager');
  * @property {Array<number>} [color4f] - The pen color as an array of [r,g,b,a], each component in the range [0,1].
  */
 
-/**
- * The pen attributes to use when unspecified.
- * @type {PenSkin#PenAttributes}
- * @memberof PenSkin
- * @private
- * @const
- */
-const DefaultPenAttributes = {
-    color4f: [0, 0, 1, 1],
-    diameter: 1
-};
-
 /**
  * Reused memory location for storing a premultiplied pen color.
  * @type {FloatArray}
@@ -161,7 +149,7 @@ class PenSkin extends Skin {
     drawLine (penAttributes, x0, y0, x1, y1) {
         // For compatibility with Scratch 2.0, offset pen lines of width 1 and 3 so they're pixel-aligned.
         // See https://github.com/LLK/scratch-render/pull/314
-        const diameter = penAttributes.diameter || DefaultPenAttributes.diameter;
+        const diameter = penAttributes.diameter;
         const offset = (diameter === 1 || diameter === 3) ? 0.5 : 0;
 
         this._drawLineOnBuffer(
@@ -222,15 +210,15 @@ class PenSkin extends Skin {
         this._renderer.enterDrawRegion(this._lineOnBufferDrawRegionId);
 
         // Premultiply pen color by pen transparency
-        const penColor = penAttributes.color4f || DefaultPenAttributes.color4f;
+        const penColor = penAttributes.color4f;
         __premultipliedColor[0] = penColor[0] * penColor[3];
         __premultipliedColor[1] = penColor[1] * penColor[3];
         __premultipliedColor[2] = penColor[2] * penColor[3];
         __premultipliedColor[3] = penColor[3];
 
         const uniforms = {
             u_lineColor: __premultipliedColor,
-            u_lineThickness: penAttributes.diameter || DefaultPenAttributes.diameter,
+            u_lineThickness: penAttributes.diameter,
             u_penPoints: [x0, -y0, x1, -y1]
         };