Re: [Dri-devel] Mesa glTexEnv bug (Was: S3TC and ut2k)

[Ian Romanick]

Leif Delgass wrote:

On Thu, 2 Jan 2003, Daniel Vogel wrote:

A bit unrelated:

Log: OpenGL Error: GL_INVALID_ENUM (UOpenGLRenderDevice::Unlock)
(if anyone wants the full log let me know)

On OS X 10.2.3 this is caused by

glTexEnvi( GL_TEXTURE_ENV, GL_OPERAND2_RGB, GL_SRC_COLOR );

This is indeed one of the sources of the GL_INVALID_ENUMs; however, it
appears to be a bug in Mesa.  There seems to be a missing break after
texstate.c:423 :

--- texstate.c  Tue Jan 21 17:10:15 2003
+++ texstate.fixed.c    Tue Jan 21 17:11:19 2003
@@ -421,6 +421,7 @@
                  return;
               FLUSH_VERTICES(ctx, _NEW_TEXTURE);
               texUnit->CombineOperandRGB[2] = operand;
+              break;
            default:
                TE_ERROR(GL_INVALID_ENUM, "glTexEnv(param=%s)", operand);
               return;

Brian, does that look right to you?

I had just come across this today also. I think a better sollution would be to fold the GL_OPERAND2_{RGB,ALPHA} cases in with the GL_OPERAND[01]_{RGB,ALPHA} cases. If we care about filtering out the cases that are not valid for EXT_texture_env_combine, we should do in the inner switch in those cases.

The other INVALID_ENUMS appear to be caused by an assumption that GL_ARB_texture_cube_map is supported, which it isn't in the current DRI Radeon driver. There appear to be calls to glDisable and glTexParameter using GL_TEXTURE_CUBE_MAP_ARB even thought the extension isn't supported. At least that's what I found with MESA_DEBUG=1 just from the intro/menu screens.
I tried exporting GL_ARB_texture_cube_map from the Radeon driver and along with the above patch, it makes all the OpenGL errors go away. The lack of combine3/4 seems to be handled in the version I'm using (from the UT2003.log):

When I've had spare cycles, I've been working on ARB_texture_cube_map for the r100. It's almost working, but I think there something subtle the I'm missing. :(

Init: OpenGL: WARNING: no support for combine3/4 extensions -> not all blend modes supported

However, I still see the same corruption reported before. This could be in part because of the missing cube map support, but it looks to me like something is causing vertex data corruption. Just a guess.

ATI_texture_env_combine3 should be in the Mesa tree soon. I'm working on hardware support for the r100, but it seems to have some problems with GL_SUBTRACT and GL_MODULATE_SUBTRACT_ATI. The card seems to ignore the GL_ONE_MINUS_SRC_{COLOR,ALPHA} and treats it like GL_SRC_{COLOR,ALPHA}. That one really has me baffled.

Are subtract problems on r100 an known issue?



-------------------------------------------------------
This SF.net email is sponsored by: Scholarships for Techies!
Can't afford IT training? All 2003 ictp students receive scholarships.
Get hands-on training in Microsoft, Cisco, Sun, Linux/UNIX, and more.
www.ictp.com/training/sourceforge.asp
_______________________________________________
Dri-devel mailing list
[EMAIL PROTECTED]
https://lists.sourceforge.net/lists/listinfo/dri-devel