[Mesa-dev] [PATCH 03/10] mesa: add new enum MAX_UNIFORM_LOCATIONS

[Ian Romanick]

On 05/19/2014 10:20 PM, Tapani wrote:
> On 05/19/2014 08:26 PM, Ian Romanick wrote:
>> On 04/09/2014 02:56 AM, Tapani Pälli wrote:
>>> Patch adds new implementation dependent value required by the
>>> GL_ARB_explicit_uniform_location extension. Default value for user
>>> assignable locations is calculated as sum of MaxUniformComponents
>>> for each stage.
>>>
>>> Signed-off-by: Tapani Pälli <tapani.palli at intel.com>
>>> ---
>>>   src/mesa/main/context.c              | 10 +++++++++-
>>>   src/mesa/main/get.c                  |  1 +
>>>   src/mesa/main/get_hash_params.py     |  1 +
>>>   src/mesa/main/mtypes.h               |  5 +++++
>>>   src/mesa/main/tests/enum_strings.cpp |  1 +
>>>   5 files changed, 17 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/src/mesa/main/context.c b/src/mesa/main/context.c
>>> index 860ae86..8b77df1 100644
>>> --- a/src/mesa/main/context.c
>>> +++ b/src/mesa/main/context.c
>>> @@ -610,8 +610,16 @@ _mesa_init_constants(struct gl_context *ctx)
>>>      ctx->Const.MaxUniformBlockSize = 16384;
>>>      ctx->Const.UniformBufferOffsetAlignment = 1;
>>>   -   for (i = 0; i < MESA_SHADER_STAGES; i++)
>>> +   /* GL_ARB_explicit_uniform_location, initial value calculated
>>> +    * as sum of MaxUniformComponents for each stage.
>>> +    */
>>> +   ctx->Const.MaxUserAssignableUniformLocations = 0;
>>> +
>>> +   for (i = 0; i < MESA_SHADER_STAGES; i++) {
>>>         init_program_limits(ctx, i, &ctx->Const.Program[i]);
>>> +      ctx->Const.MaxUserAssignableUniformLocations +=
>>> +         ctx->Const.Program[i].MaxUniformComponents;
>>> +   }
>> This is just going to set ctx->Const.MaxUserAssignableUniformLocations
>> to 4 * 4 * MAX_UNIFORMS, and that's probably not what we want.  Maybe
>> just set 4 * MAX_UNIFORMS with a comment saying it's, "MAX_UNIFORMS for
>> each possible shader stage."
> 
> There should be much more locations than number of uniforms though (?)
> MAX_UNIFORMS refers to count of available vec4 uniforms, each of these
> should have 4 locations available. Also, value from the above formula
> nicely matches with binary drivers so IMO it shouldn't be 'too much'.

It occured to me later that 4 * 4 * MAX_UNIFORMS is actually more
correct... because you could have MAX_UNIFORMS float uniforms per stage,
and you'd like to be able to give each of them a location. :)  So I
guess just explicitly set it to 4 * 4 * MAX_UNIFORMS outside the loop
instead of calculating the value in the loop.

>>>      ctx->Const.MaxProgramMatrices = MAX_PROGRAM_MATRICES;
>>>      ctx->Const.MaxProgramMatrixStackDepth =
>>> MAX_PROGRAM_MATRIX_STACK_DEPTH;
>>> diff --git a/src/mesa/main/get.c b/src/mesa/main/get.c
>>> index 6d95790..8b50441 100644
>>> --- a/src/mesa/main/get.c
>>> +++ b/src/mesa/main/get.c
>>> @@ -395,6 +395,7 @@ EXTRA_EXT(ARB_viewport_array);
>>>   EXTRA_EXT(ARB_compute_shader);
>>>   EXTRA_EXT(ARB_gpu_shader5);
>>>   EXTRA_EXT2(ARB_transform_feedback3, ARB_gpu_shader5);
>>> +EXTRA_EXT(ARB_explicit_uniform_location);
>>>     static const int
>>>   extra_ARB_color_buffer_float_or_glcore[] = {
>>> diff --git a/src/mesa/main/get_hash_params.py
>>> b/src/mesa/main/get_hash_params.py
>>> index 06d0bba..5709d42 100644
>>> --- a/src/mesa/main/get_hash_params.py
>>> +++ b/src/mesa/main/get_hash_params.py
>>> @@ -474,6 +474,7 @@ descriptor=[
>>>     [ "MAX_LIST_NESTING", "CONST(MAX_LIST_NESTING), NO_EXTRA" ],
>>>     [ "MAX_NAME_STACK_DEPTH", "CONST(MAX_NAME_STACK_DEPTH), NO_EXTRA" ],
>>>     [ "MAX_PIXEL_MAP_TABLE", "CONST(MAX_PIXEL_MAP_TABLE), NO_EXTRA" ],
>>> +  [ "MAX_UNIFORM_LOCATIONS",
>>> "CONTEXT_INT(Const.MaxUserAssignableUniformLocations), NO_EXTRA" ],
>> Ditto on Petri's comment.
>>
>>>     [ "NAME_STACK_DEPTH", "CONTEXT_INT(Select.NameStackDepth),
>>> NO_EXTRA" ],
>>>     [ "PACK_LSB_FIRST", "CONTEXT_BOOL(Pack.LsbFirst), NO_EXTRA" ],
>>>     [ "PACK_SWAP_BYTES", "CONTEXT_BOOL(Pack.SwapBytes), NO_EXTRA" ],
>>> diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
>>> index 7ac6bbe..fefbe06 100644
>>> --- a/src/mesa/main/mtypes.h
>>> +++ b/src/mesa/main/mtypes.h
>>> @@ -3311,6 +3311,11 @@ struct gl_constants
>>>      GLuint UniformBufferOffsetAlignment;
>>>      /** @} */
>>>   +   /**
>>> +    * GL_ARB_explicit_uniform_location
>>> +    */
>>> +   GLuint MaxUserAssignableUniformLocations;
>>> +
>>>      /** GL_ARB_geometry_shader4 */
>>>      GLuint MaxGeometryOutputVertices;
>>>      GLuint MaxGeometryTotalOutputComponents;
>>> diff --git a/src/mesa/main/tests/enum_strings.cpp
>>> b/src/mesa/main/tests/enum_strings.cpp
>>> index 3795700..298ff6a 100644
>>> --- a/src/mesa/main/tests/enum_strings.cpp
>>> +++ b/src/mesa/main/tests/enum_strings.cpp
>>> @@ -787,6 +787,7 @@ const struct enum_info everything[] = {
>>>      { 0x8256, "GL_RESET_NOTIFICATION_STRATEGY_ARB" },
>>>      { 0x8257, "GL_PROGRAM_BINARY_RETRIEVABLE_HINT" },
>>>      { 0x8261, "GL_NO_RESET_NOTIFICATION_ARB" },
>>> +   { 0x826E, "GL_MAX_UNIFORM_LOCATIONS" },
>>>      { 0x82DF, "GL_TEXTURE_IMMUTABLE_LEVELS" },
>>>      { 0x8362, "GL_UNSIGNED_BYTE_2_3_3_REV" },
>>>      { 0x8363, "GL_UNSIGNED_SHORT_5_6_5" },
>>>