anchor.diff:  
     matchStartColor(int pixelPos, ImageData imgData, HexColor color) {
       var r = imgData.data[pixelPos];
  -    var g = imgData.data[pixelPos+1];
  -    var b = imgData.data[pixelPos+2];
  +    var g = imgData.data[pixelPos + 1];
  +    var b = imgData.data[pixelPos + 2];
   
       return (r == color.r && g == color.g && b == color.b);
     }
   
     colorPixel(int pixelPos, ImageData imgData, HexColor color) {
       imgData.data[pixelPos] = color.r;
  -    imgData.data[pixelPos+1] = color.g;
  -    imgData.data[pixelPos+2] = color.b;
  -    imgData.data[pixelPos+3] = 255;
  +    imgData.data[pixelPos + 1] = color.g;
  +    imgData.data[pixelPos + 2] = color.b;
  +    imgData.data[pixelPos + 3] = 255;
     }
   
     fill(num x, num y, String color) {
  
positive.code:       ..on(Message.clearDrawing, (_) => clearDrawing())
        ..on(Message.undoLast, (_) => undoLast())
        ..on(Message.existingCanvasLayers, (x) => existingCanvasLayers(x));
  
    }
  
    drawPoint(DrawPoint drawPoint) {
  
negative.code: 
      strokeCanvasLayers();
    }
  }
  