[whatwg] setting canvas colors as array

Anne van Kesteren annevk at opera.com
Sat Oct 4 03:28:35 PDT 2008

On Sat, 04 Oct 2008 12:19:03 +0200, Oliver Hunt <oliver at apple.com> wrote:
> Ah, I was not meaning to in any way suggest that we change the type of  
> fillStyle/strokeStyle, merely to overload the assignment behaviour to  
> allow arrays to be used -- although i'm not sure whether there is a  
> clean way to represent this in the idl definitions in the spec.
> Basically i would expect
> context.fillStyle = [1,1,1,0.5]
> alert(context.fillStyle);
> to produce an output akin to rgba(255,255,255,0.5) or some such.
> The goal is simply to make a very common idiom (computed colours) be  
> much more concise.  As I have said previously webkit also provides a  
> setFillColor(r,g,b,a) method which might be preferable? (the problem  
> with this kind of approach is that it means that there are two distinct  
> methods to set the active colour :-/ )

I think the array approach is better. Given that addColorStop also exists  
we'd have to add three extra methods and one for each new member that does  
something with color. On top of that, the existing members are already  
overloaded to also take CanvasGradient and CanvasPattern so it would be  
more consistent.

Anne van Kesteren

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