[Mesa-dev] updating tex combine for frag program

[Ian Romanick]

On 02/07/2012 12:08 PM, Dave Airlie wrote:
> Hi guys,
>
> Is there any reason we need to update tex combiner state if we are
> using shaders?
>
> can we drop update_tex_combine updates to only the case where we don't
> have a fragment shader/program unless its from the FF shader?

I don't recall when update_tex_combine happens.  Does it happen at 
draw-time or state change-time?  If it happens at state change-time, the 
state will need to get updated when program 0 gets bound.  Otherwise 
something like the following would break:

	glUseProgram(my_prog);
	glTexEnvi(GL_TEXTURE_2D, GL_TEXTURE_ENV_MODE,
		GL_DECAL);
	glUseProgram(0);
	glDrawArrays(...);