[whatwg] createImageData should take unsigned long
bzbarsky at MIT.EDU
Thu Sep 3 05:57:27 PDT 2009
Philip Jägenstedt wrote:
> I wasn't involved then, but I can only presume that there was no
> perceived benefit of high-DPI ImageData since you can get high-quality
> rendering just as well with techniques that don't rely on the canvas
> being higher resolution than the display device.
To be clear, in this context "high-DPI" means "using the DPI of the
display device, instead of the about 96dpi you get with CSS pixels".
So if this were done and I have a 300-dpi screen, there would be, say, 3
imagedata pixels per CSS pixel. If you have a 200-dpi screen, then on
our computer there would be 2 imagedata pixels per CSS pixel. Script
would have to be able to deal with this, which is where the APIs like
createImageData(imageData) come in.
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