Bind a fragment output to both a color number and a color index (0 or 1
for dual-source blending), and report the bound index back through
glGetFragDataIndex.
- ProgramObject now tracks a per-output color index alongside the
location: SetExplicitFragmentOutIndex stores it, it is snapshotted into
the linked map at link time (like the location map), and
GetFragmentDataIndex returns it (0 by default) for an active output.
- glBindFragDataLocation becomes glBindFragDataLocationIndexed with index
0, matching the GL definition, so it also resets a previously-bound
index to 0.
- Validation: index must be 0 or 1 (GL_INVALID_VALUE); colorNumber is
bounded by GL_MAX_DRAW_BUFFERS for index 0 and GL_MAX_DUAL_SOURCE_DRAW_BUFFERS
(reported as 1) for index 1 (GL_INVALID_VALUE); a gl_ name is
GL_INVALID_OPERATION.
- glGetFragDataIndex now returns the real bound index instead of a
hardcoded 0.
The index is tracked for reflection but is not yet plumbed into dual-source
blend rendering, and shader-side layout(index=) qualifiers are not
reflected -- both documented at the call sites.
Tests: index round-trip through a re-link (bind 1 -> GetFragDataIndex == 1;
glBindFragDataLocation resets to 0), plus the validation error table;
mutation-verified end to end. ProgramTest 24/24.
Fill the stubbed GL 3.3 Core glGetFragDataIndex, mirroring its already-
implemented sibling glGetFragDataLocation: validate the program object and
link status, then return the fragment color index the name binds to.
Every active user-defined output uses color index 0. MobileGL does not yet
track dual-source (index 1) bindings -- glBindFragDataLocationIndexed and
the layout(index = 1) qualifier are unsupported -- so the result is exact
for any program that does not use dual-source blending; a name that is not
an active output (including gl_ built-ins) returns -1.
Tests: assertions on the existing linked-program test (valid output -> 0,
unknown name -> -1) plus a standalone invalid-handle case. The invalid-
handle test drains the error queue it produces so no stale error leaks
into a later test (the ProgramTest fixture does not reset it). ProgramTest
24/24.
Completes the uniform-block reflection chain: glGetUniformIndices, glGetActiveUniformName
and glGetActiveUniformBlockiv were already implemented; glGetActiveUniformsiv was the last
stub. Supports all 8 GL 3.3 Core pnames:
* GL_UNIFORM_TYPE / SIZE / NAME_LENGTH / BLOCK_INDEX / OFFSET / ARRAY_STRIDE come straight from
glslang's TObjectReflection (the same reflection the existing uniform queries use).
* GL_UNIFORM_IS_ROW_MAJOR from the member's TType layout qualifier, guarded by isMatrix() so a
scalar in a layout(row_major) block does not wrongly report 1.
* GL_UNIFORM_MATRIX_STRIDE is derived: glslang exposes no matrix stride, so it is computed from the
std140 rule (each column/row vector rounded up to a vec4), which matches the std140 layout
MobileGL's SPIR-V path emits. Evaluates to 16 for every GL 3.3 float matrix.
The -1-vs-0 distinction is handled explicitly: OFFSET / ARRAY_STRIDE / MATRIX_STRIDE / BLOCK_INDEX
return -1 for a default-block uniform (glslang gives arrayStride 0 there, so it is gated on block
membership), while ARRAY_STRIDE / MATRIX_STRIDE return 0 for a non-array / non-matrix member that IS
in a block. Errors: GL_INVALID_VALUE for uniformCount<0, any index >= active uniform count, or a
never-generated program name; GL_INVALID_OPERATION for a live shader name; GL_INVALID_ENUM for an
unaccepted pname (e.g. the GL 4.2 GL_UNIFORM_ATOMIC_COUNTER_BUFFER_INDEX). All validation runs before
any write, so params is untouched on error. There is no "not linked" error -- an unlinked program has
zero active uniforms, so any index raises GL_INVALID_VALUE.
Also fix GetActiveUniformArraySize, which returned glslang's TObjectReflection.size verbatim: that
field only carries the element count for a non-block array and reports 1 for a block array member,
so GL_UNIFORM_SIZE (and glGetActiveUniform's size out-param, and glGetProgramResourceiv's
GL_ARRAY_SIZE) wrongly reported 1 for an array inside a UBO. Take the count from the TType instead,
which is authoritative for both cases.
Covered by 3 ProgramTest cases (std140 block with scalar/array/mat4 + a default-block sampler, a
row_major variant, and the six error cases) that link real shaders and assert every pname value.