[Mesa-dev] [PATCH 07/23] mesa: glGetProgramResourceLocationIndex

[Ilia Mirkin]

On Tue, Mar 17, 2015 at 5:13 AM, Tapani Pälli <tapani.palli at intel.com> wrote:
>
>
> On 03/16/2015 08:08 PM, Ilia Mirkin wrote:
>>
>> On Fri, Mar 13, 2015 at 4:37 AM, Tapani Pälli <tapani.palli at intel.com>
>> wrote:
>>> +/**
>>> + * Returns output index for dual source blending.
>>> + */
>>>   GLint GLAPIENTRY
>>>   _mesa_GetProgramResourceLocationIndex(GLuint program, GLenum
>>> programInterface,
>>>                                         const GLchar *name)
>>>   {
>>> -   return -1;
>>> +   GET_CURRENT_CONTEXT(ctx);
>>> +   struct gl_shader_program *shProg =
>>> +      lookup_linked_program(program,
>>> "glGetProgramResourceLocationIndex");
>>> +
>>> +   if (!shProg || invalid_array_element_syntax(name))
>>> +      return -1;
>>> +
>>> +   /* From the GL_ARB_program_interface_query spec:
>>> +    *
>>> +    * "For GetProgramResourceLocationIndex, <programInterface> must be
>>> +    * PROGRAM_OUTPUT."
>>> +    */
>>
>>
>> And presumably it must be a program with a fragment shader (which
>> might not be there for a no-rast or compute pipeline).
>
>
> spec says that -1 is returned:
>
> "If <program> has been successfully linked but contains no fragment shader,
> no error will be generated but -1 will be returned."
>
> this is what happens with the implementation.

Can you explain how the current implementation takes care of that?