Re: RE: [PATCH] Fix glReadPixels call from read_from_framebuffer (re-redux)

[Roderick Colenbrander]

We have both a glDrawPixels and texture backend. You can switch to a different backend using the RenderTargetLockMode registry key. It has values readdraw (readpixels + drawpixels), readtex (readpixels + texture rendering) and some others (textex and texdraw).

I plan on making readtex default at some point.

Roderick
> Why not create a texture and draw a quad instead of using glDrawPixels (as
> it is deprecated in gl3)?Reference -- ogl 3 spec --
> (http://www.opengl.org/registry/doc/glspec30.20080811.pdf)Under "E.1 Profiles and Deprecated
> Features of OpenGL 3.0""Pixel drawing - DrawPixels and PixelZoom (section
> 3.7.4). However, the 
> language describing pixel rectangles in section 3.7 is retained as it is
> required 
> for TexImage* and ReadPixels. " - Nick> From: [e-mail]> To:
> [e-mail]; [e-mail]> Subject: RE: [PATCH] Fix
> glReadPixels call from read_from_framebuffer	(re-redux)> Date: Tue, 23 Dec 2008
> 11:11:08 -0800> > > Thanks for reviewing my patch (it sure makes the SHOGO
> menu much nicer)> BTW do you know if I need to resubmit my other SHOGO patch
> ([PATCH] Fix ddraw surface version setting)?> > > Concerning negative
> pixelzoom and drawpixels on R500> Please file a radar on that (and email the
> mac-opengl mailing list)> > >  - Nick> >
> ---------------------------------------->> From: [e-mail]>> To: [e-mail]>> Subject:
> RE: [PATCH] Fix glReadPixels call from read_from_framebuffer (re-redux)>>
> Date: Tue, 23 Dec 2008 13:30:40 +0100>>>> This patch looks good.>>>> There's
> one last thing we should check: It seems that this is the only code>> that
> uses GL_PACK_ROW_LENGTH and friends, so the backup and restore is>>
> probably not needed. I think for now it is better to add it because I>> suspect
> the code in surface_download_data most likely depends on the default>>
> settings without properly controlling them.>>>> There's some related driver bug
> on OSX too(no radar filed yet,>> unfortunately). Using a PBO for
> glDrawPixels with a negative pixelzoom(wine>> uses -1 for y) breaks at least on my
> radeon X1600 with MacOS 10.5.5. I>> haven't yet tested it with 10.5.6, but if
> it is still broken there I have to>> remember to file a bug. It is sort of
> a follow-up bug to a bug fixed in>> 10.5.5; Before that glPixelZoom and
> PixelPos were completely ignored with>> PBOs.>>>> This bug was on my todo
> list for a long time by the way. I wanted to fix it,>> got distracted and
> forgot again :-/