[whatwg] isPointInPath v. set of pixels in canvas hit regions

Hi,

As things currently stand in the spec, implementations basically need to
keep N+1 bitmaps per canvas, where N is the number of hit regions. I
doubt any implementors would be enthusiastic to implement hit regions
like this. From a WebKit perspective, we'd much prefer keeping a Path
for each hit region, and then simply using isPointInPath for hit
testing. This also implies that the current piggybacking of "Clear
regions that cover the pixels" in clearRect() could go away. Yay! :)


Ted