[whatwg] proposed canvas 2d API additions

Anne van Kesteren fora at annevankesteren.nl
Tue May 9 01:26:27 PDT 2006

Quoting Vladimir Vukicevic <vladimirv at gmail.com>:
>> I agree that they shouldn't be affected by the CTM, but I disagree that
>> they should be integers. e.g. in cases like:
>>   HTML                          CSS
>>   <canvas height=1 width=1>     canvas { height: 100%; width: 100%; }
>>   </canvas>
>> ...where the JS then uses the coordinate space 0..1,0..1 the author might
>> want to grab the top corner by grabbing the 0,0,0.25,0.25 rect.
> So, I really don't like this -- we need to nail down space the
> getPixels/setPixels coordinates should be in.  I still think that they
> should always be in the canvas space, no matter how many pixels they
> refer to in the rendered content or in the device space.  Note that in
> your example, the canvas can still be a 1x1 pixel canvas (and, I
> believe, will be in all current implementations) -- that one pixel
> will just cover the entire page.

That is what Ian is saying. He's saying it's a 1x1 pixel canvas just  
that within that 1x1 pixel there could be different subpixels with  
different colors you could try to get using floating points instead of  

Anne van Kesteren

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