[whatwg] setting canvas colors as array

Oliver Hunt oliver at apple.com
Sat Oct 4 03:19:03 PDT 2008

On Oct 4, 2008, at 3:07 AM, Anne van Kesteren wrote:

> On Sat, 04 Oct 2008 01:37:53 +0200, Oliver Hunt <oliver at apple.com>  
> wrote:
>> <thinking out loud>
>> Just had a thought (no idea how original) -- how about if fillStyle  
>> were able to accept a 3 or 4 number array? eg. fillStyle = [0, 0.3,  
>> 0.6, 1.0] ?
>> That might work well if people are using arrays as vectors/colours
>> </thinking out loud>
> Philip Taylor suggested that a while back:
>  http://lists.whatwg.org/pipermail/whatwg-whatwg.org/2007-April/010939.html
> Ian Hickson replied only to the added value of returning an array  
> rather than a string:
>  http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2007-May/011268.html
> (Which at this point is unfortunately no longer possible I'm afraid.)

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]
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 :-/ )


> -- 
> Anne van Kesteren
> <http://annevankesteren.nl/>
> <http://www.opera.com/>

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