as.restore</a> is called. Each call to <a href="dart-ui/Canvas/saveLayer.html">Canvas.saveLayer</a> introduces a new
layer onto which shapes and images are painted; when <a href="dart-ui/Canvas/restore.html">Canvas.restore</a> is
called, that layer is then composited onto the parent layer, with the source
being the most-recently-drawn shapes and images, and the destination being
the parent layer. (For the first <a href="dart-ui/Canvas/saveLayer.html">Canvas.saveLayer</a> call, the parent layer
is the canvas