docs: function iterator ()
          {
              // Begin by clearing the canvas
              RG.clear(obj.canvas, color);
  
              obj.context.save();
                  // First draw the circle and clip to it
                  obj.context.beginPath();
                  obj.context.arc(centerx, centery, currentRadius, 0, RG.TWOPI, false);
                  obj.context.clip();
                  
                  // Clear the canvas to a white color
                  if (opt.background) {
                      RG.clear(obj.canvas, opt.background);
                  }
                  
                  // Now draw the chart
                  obj.Draw();
              obj.context.restore();
  
  
              // Increment the radius
              if (currentRadius < targetRadius) {
                  currentRadius += step;
                  RG.Effects.updateCanvas(iterator);
  
              } else {
                  callback(obj);
              }
          }