[Mesa-dev] [PATCH] meta: Add GLSL variant of _mesa_meta_GenerateMipmap() function

[Ian Romanick]

On 08/28/2012 08:58 AM, Brian Paul wrote:
> On 08/28/2012 12:14 AM, Anuj Phogat wrote:
>> This reduces the overhead of using the fixed function internally
>> in the driver.
>>
>> Note: ARB_fragment_shader is not present in intel->gen<  4. I'll send
>> out a separate patch to avoid enabling _mesa_meta_GenerateMipmap() in
>> those chips.
>> No regressions observed in all.tests with this patch. Need more testing
>> for integer textures.
>
> A recent ARB bug report points out that linear filtering is not
> supported for integer textures.  And thus, there's some question about
> what to do for automatic mipmap generation of integer textures.  It
> doesn't always make sense to average four integer texels to produce a
> new one.
>
> I'll monitor the bug and see what the ARB decides on.  We might wind up
> just raising GL_INVALID_OPERATION.

I just noticed that today as well.  In the interest of keeping the 
release somewhat on track, could we commit Anuj's patch (I still haven't 
fully reviewed it... it's the top of my to-do list for today) 
functionally as-is?  If Khronos decides that glGenerateMipmap on an 
integer texture should generate an error, we can implement that as a bug 
fix.