The text for drawImage currently states:
When drawImage() is invoked, the region of the image specified by the source rectangle must be painted on the region of the canvas specified by the destination rectangle, after applying the current transformation matrix to the points of the destination rectangle.
This is a bit confusing since you don't really apply the transform to the points. Basically, you map the source rect to the destination rect and then transform the destination rectangle.
I believe the spec should also call out that there should be no loss of precision when doing this (i.e. if the destination has half the pixels but scaled by 2, the original pixel should be preserve)
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Applying the matrix is not on the points of a rectangle. Also clarified that the original image is not updated.
Have you suggested this change to Ian?
No, I thought he was watching our bugs as well. I'd be glad to suggest it. (In reply to comment #2)
> Have you suggested this change to Ian?
Note, he made this change: