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Re: [Public WebGL] readPixles() can't access float values (OES_texture_float interaction)

On Thu, Sep 1, 2011 at 11:50 AM, Mark Callow <[email protected]> wrote:

I have it on the best of authority (Maurice Ribble who works on the driver) that the Adreno 220 does not support rendering to FP buffers. As for the Tegra I see the words on page 5 however the list of extensions does not list any that would enable this functionality. The most likely suspect for this, GL_NV_fbo_color_attachments, only mentions half-float.

As others have said, OES_texture_float is not the place to enable this functionality. Another extension is needed but I do not think there is enough commonality in behaviour across implementations for sch an extension to be viable for WebGL at present.

I think the point others brought up is does this need an extension at all?

As far as I recall, OpenGL ES 2.0 makes no promises about what types of textures can be bound to frame buffers. The only way to know is to bind one and then call glCheckFramebufferStatus.  

So, do we need a specific extension to enable rendering to floating point textures or is the current situation good enough?




On 2011/08/31 15:37, David Sheets wrote:
Page 5 of the NVidia Tegra GL ES 2 docs
indicates FP texture write support (and MRT fwiw). Adreno 220 series
can do deferred lighting and cloth sim which would also seem to
indicate FP texture write support.