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Re: Canvas in FX

From: Charles Pritchard <chuck@jumis.com>
Date: Tue, 23 Nov 2010 15:30:49 -0800
Message-ID: <4CEC4EA9.90401@jumis.com>
To: "Tab Atkins Jr." <jackalmage@gmail.com>
CC: public-fx@w3.org, robert@ocallahan.org
On 11/23/2010 3:04 PM, Tab Atkins Jr. wrote:
> On Mon, Nov 22, 2010 at 4:04 PM, Charles Pritchard<chuck@jumis.com>  wrote:Hello FX list.
>> WebKit introduced getCSSCanvasContext quite some time ago:
>> http://webkit.org/blog/176/css-canvas-drawing/
...
>> This is intended strictly for CSSCanvas, even though I'm using the
>> HTMLCanvas tag:
>>
>> <svg><g style="scale(1.5, 1.5)"><canvas></canvas></g></svg>
...
>> I realize this is my first post on the list, and I haven't fully explained
>> the use case. But I thought I'd start somewhere.
>>
>> The canvas backing store is a bitmap. That's how it works. That backing
>> store size could be dynamically increased and decreased, to best match the
>> css resolution of its containing group.
> Apologies, but I don't understand whatsoever what you're trying to do
> here.  I followed the thread where you originally talked with roc, but
> I can't understand how you got from there to here, or even what "here"
> is.
>
> Could you try to explain what you're trying to achieve in a different way?
It's certainly my fault; I've got a solution in search of a problem.

I'm trying to develop the concept of the "CSS Canvas" opposed to the 
HTML Canvas, as I feel that exploring possible "CSS Canvas" semantics, 
is a necessary step in bringing canvas functionality into SVG.
Beyond that, my thoughts and ideas are not well formed (though they are 
informed).

Lets consider canvas a paint server (instead of an element), as it makes 
good sense within the context of CSS+SVG.

When using a gradient as a paint server, implementations manage the 
composition of that gradient, it doesn't create a small bitmap and then 
scale it up -- it manages the fill to match the resolution/size of the 
container. Regardless of scale/zoom, I should see a nice gradient.

I'd like to something like this to happen when a CSS Canvas context is 
used as a paint server.
"fillRect + createLinearGradient", for instance, would be as well 
managed as "linearGradient" / css gradients.

Does that make sense/help? I'm happy to provide more examples.

-Charles
Received on Tuesday, 23 November 2010 23:30:52 GMT

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