[whatwg] [canvas] request for {create, get, put}ImageDataHD and ctx.backingStorePixelRatio

Charles Pritchard chuck at jumis.com
Tue Mar 20 14:33:32 PDT 2012

On Mar 20, 2012, at 1:42 PM, Edward O'Connor <eoconnor at apple.com> wrote:

> But now run through this logic when the <canvas> is making a high res
> backing store automatically: by doing the clever thing, you're now
> quadrupling the size of the canvas, and you're paying an exorbitant
> storage cost for doing so.

Which (a): never happens and (b) can be detected via 1x1 pixel canvas.

> You really only want to do the "make it twice as big and then scale it
> down with CSS" trick when backing store pixels are 1:1 to CSS pixels.

I do "tricks" to support browser zoom. They are increments; .5,.7, 1.1, 1.2, 1.3, etc. 


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