Looking at the tdfx driver I see this: /* FIXME: Combine this into one call... */ FALLBACK( tmesa, TDFX_FALLBACK_BLEND_EQ, mode != GL_FUNC_ADD_EXT ); FALLBACK( tmesa, TDFX_FALLBACK_BLEND_EQ, ctx->Color.ColorLogicOpEnabled && ctx->Color.LogicOp != GL_COPY ); This is broken because the two conditions attempt to use a single bit. Imagine the case where (mode == GL_FUNC_ADD_EXT) but (ctx->Color.ColorLogicOp == GL_COPY): The first call will install a fallback, but the second will immediately clear the fallback... The solution is to associate a single logical condition for each bit in the fallback mask. In this case you could combine the two conditions with a disjunctive, or alternatively use different bits in the mask for the two conditions. Keith _______________________________________________ Dri-devel mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/dri-devel