anchor.diff:  
       // transform/draw each star
       for (Star s in _stars) {
  -      _drawSceneStar(s);
  +      _drawStar(s);
         _spin += 0.1;
       }
   
  
positive.code:   }
  
    // replacement method for Star.prototype.draw in JS version
    void _drawSceneStar(Star star) {
      _mvPushMatrix();
  
      // Move to the star's position
  
negative.code: 
      // Draw the star in its main color
      _gl.uniform3f(_uColor, star.r, star.g, star.b);
      _renderStar();
  
      _mvPopMatrix();
    }
  
    /**
     * Do the actual webgl drawing of star geometry and applying the texture.
     */
    void _renderStar() {
      _gl.activeTexture(webgl.RenderingContext.TEXTURE0);
      _gl.bindTexture(webgl.RenderingContext.TEXTURE_2D, _texture);
      _gl.uniform1i(_uSampler, 0);
  