Re: [SVG 1.2 draft]: 17.3 Media Interfaces - getPixel()

On Sat 17 Jul 2004, Jim Ley wrote:

> 
> 
> "Chris Lilley" <chris@w3.org> wrote in message 
> news:792044751.20040717184656@w3.org...
> >
> > On Saturday, July 17, 2004, 12:28:47 PM, Jim wrote:
> > JL> So there's no change allowing getPixel work on SVG Canvases aswell 
> > then?
> >
> > JL> That's a shame, what's the problem with it?
> >
> > OK, try to specify what it does in the general case.
> 
> Rasterise the SVG canvas, and use getPixel exactly as you do on a Raster 
> image.
> 
> The existing draft doesn't mention much about what the X and Y longs refer 
> to in getPixel  I guess the intention is that it's raster pixel in the 
> co-ordinate space of the image, otherwise you'd have the same sampling 
> problems as with Vector formats I guess.

That's right. We mean (x,y) in the raster image coords.

>  In which case all you need to 
> define is the size (so whole units in the user coordinate space maybe, or in 
> terms of pixel for example.) of the image to be rastered before being able 
> to call getPixel on it.

That might be possible, but some implementations don't want to 
rasterize.

Dean