----- Original Message -----
From: "Ian Hickson" <[EMAIL PROTECTED]>
Subject: Re: [whatwg] "canvas" tag and animations ?
On Tue, 16 May 2006, Andrew Fedoniouk wrote:
|
| Canvases are automatically double-buffered.
Why? Is this a requirement?
Not in theory, but in practice it is. Early Opera implementations didn't
do this and the performance was too slow for practical use.
This does not mean that acceptable implementation without double-buffering
is not possible or does not make sense.
For simple cases like custom bullet for the list it makes sense to have one
of
these (or combination of these):
1) non-buffered draw, small area to draw and simple image. If
buffered draw needed - use Image;
2) or to have getGraphics defined as
getGraphics("what",x,y,width, height, backgroundColor = transparent) or
3) or to be able to say for example
element.style.listStyleImage = new Image();
4) or in <style> to define
li { list-style-image: url("script: nameOfVariableHoldingImage;"); }
(assumption was made that getGraphics/Canvas will be available
for any element)
Andrew Fedoniouk
http://terrainformatica.com
