Re: [css shaders] tiling large elements

Ok, that makes sense -- I like the idea of scaling the element's
rendering down to fit inside a texture as it passes no additional
complexity on to the shader. Blur and related shaders would work with
a margin, but a lot of effects (e.g.: wrapping the element, as if
simulating an old TV with broken vertical hold) wouldn't.

Ralph

On Sun, Oct 16, 2011 at 7:01 PM, Vincent Hardy <vhardy@adobe.com> wrote:
> From: Ralph Thomas <ralpht@gmail.com>
> Date: Sat, 15 Oct 2011 20:36:08 -0700
> To: "public-fx@w3.org" <public-fx@w3.org>
> Subject: [css shaders] tiling large elements
>
> Hi,
>   How could a tiling scheme be implemented for CSS Shaders if the
> element being shaded is larger than a texture may be given that (I
> think!) the shader would expect the whole element to be in a single
> texture?
> Thanks,
> Ralph
>
>
>
> Hi Ralph,
> The shaders, as currently proposed, work with the assumption that the whole
> element's rendering is available. If that was not the case, then we could
> pass in additional uniforms to the shader.
> However, to account for resource constraints, the implementations could
> reduce the texture size. Doing multiple passes with different textures for
> each tile would not work for some shaders, for example, a blur would not
> work out of the box, without taking extra steps (e.g., have a notion of tile
> margin the shader would need to still operate).
> Cheers,
> Vincent