Re: [css-shaders] subdivision for transparency

On 05/10/2011, at 10:18 AM, Tab Atkins Jr. wrote:

> On Tue, Oct 4, 2011 at 4:05 PM, Gregg Tavares (wrk) <gman@google.com> wrote:
>> On Tue, Oct 4, 2011 at 3:35 PM, Robert O'Callahan <robert@ocallahan.org>
>> wrote:
>>> On Wed, Oct 5, 2011 at 9:13 AM, Dean Jackson <dino@apple.com> wrote:
>>>> 
>>>> As for filters, I was really hoping that we'd be able to specify them as
>>>> purely a 2d effect - as in whatever is composited in the end is a quad, not
>>>> a mesh, even if the filter itself uses a mesh.
>>> 
>>> I totally agree. The result of a "custom" filter primitive is flattened to
>>> an image. Nothing else makes sense, even within a filter chain
>> 
>> That's fine in all you want to achieve is filtering effects but that doesn't
>> fit with the examples shown by Adobe. They're morphing the content in 3d.
>> http://www.adobe.com/devnet/html5/articles/css-shaders.html#1
>> In one case they're morphing something to look like a newspaper. It unfolds
>> but is still interactive once it unfolds.
>> In another case they're morphing a twitter feed a kind of wavy shape and
>> they are interacting with it while it's in this wavy shape. I don't see why
>> the user would think it's not 100% interactive.
>> So it seems like for this proposal to be generally useful that content needs
>> to able to be interactive (ie, the user needs to able to click on stuff just
>> like they can with 3d css). Otherwise the number of use cases for it seems
>> exceedingly small.
> 
> Note that vertex shaders (what, I think, were used to achieve the
> effects that Greg mentioned) are reversible, though it requires the
> shader to be run on the CPU (I think), so you can still handle mouse
> interaction.  Pixel shaders aren't, but that's not something fixable.

The problem is that it might be computationally expensive to do this mapping each time the pointer moves, and also is a fairly high burden on some implementations (write your own GLSL engine).

Dean

Received on Tuesday, 4 October 2011 23:27:39 UTC