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Re: [Public WebGL] Why have readpixels support 5_6_5?



To removing it outright, and leaving RGBA8888 as the only readpixels format?  Not from me.  I can't think of a situation where 565 readback would be a performance win (for feeding to anything else on the Web API side).

    - Vlad

----- Original Message -----
> I doubt that any serious incompatibilities would be introduced by
> leaving in the support for the implementation color read format and
> type, or even having different browsers return different values on the
> desktop. Existing OpenGL ES 2.0 apps on mobile devices seem to achieve
> good portability.
> 
> That having been said, upon more thought it seems fine to remove it
> since RGBA8888 must be supported, and in the spirit of moving the spec
> toward completion I think we should do so. Any objections?
> 
> -Ken
> 
> On Tue, Nov 2, 2010 at 2:29 AM, Mark Callow <callow_mark@hicorp.co.jp>
> wrote:
> > I agree with Tim.
> >
> > FWIW the most common implementation read format, when reading from
> > the
> > default framebuffer, is RGB565, which is why it was chosen for
> > WebGL. When
> > reading from FBOs it is probably whatever format the renderbuffer
> > is, i.e.
> > it will be dependent on both application and implementation.
> >
> > Regards
> >
> > -Mark
> >
> > On 02/11/2010 17:52, Tim Johansson wrote:
> >
> > On 2010-11-01 21:09, Vladimir Vukicevic wrote:
> >
> > Ah, I didn't realize that it could vary based on the bound
> > framebuffer.
> >
> > It was suggested that we fix the type because it was an odd
> > implementation-specific variance that wasn't covered by an extension
> > that
> > could be queried. But that made sense when we weren't thinking of it
> > as
> > framebuffer-specific; since it does vary, then I agree that it
> > doesn't make
> > sense to fix it (since most everything with fbos is
> > implementation-dependant
> > anyway!). Happy to change them back.
> >
> > If we want to change it I would prefer dropping implementation
> > dependent
> > read format and either only support RGBA8888 or require software
> > conversion
> > to support any format.
> >
> > our email:
> >
> 
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