[Mesa-dev] [PATCH] mesa: Add GL_TEXTURE_CUBE_MAP to _mesa_max_texture_levels().

[Brian Paul]

On 06/05/2012 01:16 AM, Kenneth Graunke wrote:
> For cube maps, _mesa_generate_mipmap() calls this with
> GL_TEXTURE_CUBE_MAP_ARB (the gl_texture_object's Target) rather than one
> of the faces.  This caused _mesa_max_texture_levels() to return 0, which
> resulted in maxLevels == -1 and the next line's assertion to fail.
>
> This function is called from several places.  It looks like texstorage.c
> also wants this enum to be handled, while most callers don't care.
> TexImage, CompressedTexImage, FramebufferTexture, and GetTexImage
> already appear to filter out illegal targets, so they should be fine.
>
> However, GetTexLevelParameter does rely on this function for filtering
> out invalid targets, and does not accept GL_TEXTURE_CUBE_MAP.  Special
> case this, since it apparently supports every other target.

I think glGet[Compressed]TexImage() needs the special case too.  For 
example, getteximage_error_check() also uses max levels to error check 
the target.

It might be good to beef-up the comment on _mesa_max_texture_levels() 
to clarify that the function is also used to error-check 'target' in 
various places and some care should be taken when adding support for 
new targets (GL_TEXTURE_CUBE_MAP_ARRAY someday).

-Brian