On 03/05/2014 12:35 PM, Eric Anholt wrote: > Ian Romanick <[email protected]> writes: > >> From: Gregory Hainaut <[email protected]> >> >> Now arb_separate_shader_object-GetProgramPipelineiv should pass. >> >> V3 (idr): >> * Change spec references to core OpenGL versions instead of issues in >> the extension spec. >> * Split out from previous uber patch. >> >> v4 (idr): Use _mesa_has_geometry_shaders in _mesa_UseProgramStages to >> detect availability of geometry shaders. >> >> Reviewed-by: Ian Romanick <[email protected]> >> --- >> src/mesa/main/pipelineobj.c | 115 >> ++++++++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 115 insertions(+) >> >> diff --git a/src/mesa/main/pipelineobj.c b/src/mesa/main/pipelineobj.c >> index 849c781..7149578 100644 >> --- a/src/mesa/main/pipelineobj.c >> +++ b/src/mesa/main/pipelineobj.c > >> + GLbitfield any_valid_stages = GL_VERTEX_SHADER_BIT | >> GL_FRAGMENT_SHADER_BIT; >> + if (_mesa_has_geometry_shaders(ctx)) >> + any_valid_stages |= GL_GEOMETRY_SHADER_BIT; >> + >> + if (stages != GL_ALL_SHADER_BITS && (stages & ~any_valid_stages) != 0) { > > Weird double space before &. > >> + _mesa_error(ctx, GL_INVALID_VALUE, "glUseProgramStages(Stages)"); >> + return; >> + } > >> + if (program) { >> + /* Section 2.11.1 (Shader Objects) of the OpenGL 3.1 spec (and >> probably >> + * earlier) says: >> + * >> + * "Commands that accept shader or program object names will >> + * generate the error INVALID_VALUE if the provided name is not >> the >> + * name of either a shader or program object and INVALID_OPERATION >> + * if the provided name identifies an object that is not the >> + * expected type." >> + */ >> + struct gl_shader *sh = _mesa_lookup_shader(ctx, program); >> + if (sh != NULL) { >> + _mesa_error(ctx, GL_INVALID_OPERATION, >> + "glUseProgramStages(progam is a shader object)"); >> + return; >> + } > > This block could get dropped into the shProg == NULL case below, right? > The code confused me as is.
The first block is checking whether the name is a shader, and the other
is checking that the name is a program. The neat thing is the spec says
using a shader where a program is expected gives one error, but using a
name that is neither give a different error.
You've never seen code like this elsewhere in Mesa because it's usually
handled by _mesa_lookup_shader_program_err. I'll change this code to
use that function instead.
>> +
>> + shProg = _mesa_lookup_shader_program(ctx, program);
>> + if (shProg == NULL) {
>> + _mesa_error(ctx, GL_INVALID_VALUE,
>> + "glUseProgramStages(progam is not a program object)");
>> + return;
>> + }
>
>
>> + /* Section 2.11.4 (Program Pipeline Objects) of the OpenGL 4.1 spec
>> + * says:
>> + *
>> + * "If UseProgramStages is called with program set to zero or with a
>> + * program object that contains no executable code for the given
>> + * stages, it is as if the pipeline object has no programmable stage
>> + * configured for the indicated shader stages."
>> + */
>> + if ((stages & GL_VERTEX_SHADER_BIT) != 0)
>> + _mesa_use_shader_program(ctx, GL_VERTEX_SHADER, shProg, pipe);
>> +
>> + if ((stages & GL_FRAGMENT_SHADER_BIT) != 0)
>> + _mesa_use_shader_program(ctx, GL_FRAGMENT_SHADER, shProg, pipe);
>> +
>> + if ((stages & GL_GEOMETRY_SHADER_BIT) != 0)
>> + _mesa_use_shader_program(ctx, GL_GEOMETRY_SHADER, shProg, pipe);
>> }
>
> The spec cite here doesn't seem to be explaining the code it's next to,
> to me.
That is fair... and at least partially my fault. Greg's original
comment above this code was:
/*
* 7. What happens if you have a program object current for a shader stage,
* but the program object doesn't contain an executable for that stage?
* RESOLVED: This is not an error; instead it is as though there were no
* program bound to that stage. We have two different notions for
* programs bound to shader stages. A program is "current" for a stage
* if it bound to that stage in the active program pipeline object. A
* program is "active" for a stage if it is current and it has an
* executable for this stage. In this case, the program would be current
* but not active.
* When no program is active for a stage, the stage will be replaced with
* fixed functionality logic (compatibility profile vertex and fragment),
* disabled (tessellation control and evaluation, geometry), or have
* undefined results (core profile vertex and fragment).
*/
Since the issues aren't captured in the core spec, I changed it to the
nearest thing I could find in the core spec. Comparing the code with
the old comment and the new comment, I'm not very happy with it either.
How about:
/* Enable individual stages from the program as requested by the application.
* If there is no shader for a requested stage in the program,
* _mesa_use_shader_program will enable fixed-function processing as dictated
* by the spec.
*
* Section 2.11.4 (Program Pipeline Objects) of the OpenGL 4.1 spec
* says:
*
* "If UseProgramStages is called with program set to zero or with a
* program object that contains no executable code for the given
* stages, it is as if the pipeline object has no programmable stage
* configured for the indicated shader stages."
*/
signature.asc
Description: OpenPGP digital signature
_______________________________________________ mesa-dev mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/mesa-dev
