29a.ch by Jonas Wagner

Flip Images using HTML5 Canvas

You can flip an Image using HTML5 like this:

// flip x axis
ctx.scale(-1, 1);
ctx.drawImage(img, x, y);
// flip it back again
ctx.scale(-1, 1);

You can flip along the y axis in the same way. I'm note sure how fast this transformation is, in practice so you might need to cache it if you are doing realtime graphics.