diff options
author | Paul Berry <stereotype441@gmail.com> | 2013-07-31 08:15:08 -0700 |
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committer | Paul Berry <stereotype441@gmail.com> | 2013-08-01 20:19:02 -0700 |
commit | 0026ad4994ca88a6cdd4e5ef4098469ab57bdcc1 (patch) | |
tree | b3ea77af8a0ae4c5a9482b3fe0b386b53ec4aa01 /src/glsl/glsl_types.cpp | |
parent | 906eff09e374c75b0486011b73b7048f6070456e (diff) |
Move count_attribute_slots() out of the linker and into glsl_type.
Our previous justification for leaving this function out of glsl_type
was that it implemented counting rules that were specific to GLSL
1.50. However, these counting rules also describe the number of
varying slots that Mesa will assign to a varying in the absence of
varying packing. That's useful to be able to compute from outside of
the linker code (a future patch will use it from
ir_set_program_inouts.cpp). So go ahead and move it to glsl_type.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Diffstat (limited to 'src/glsl/glsl_types.cpp')
-rw-r--r-- | src/glsl/glsl_types.cpp | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/src/glsl/glsl_types.cpp b/src/glsl/glsl_types.cpp index 8324b8ade7a..0c639b3eb87 100644 --- a/src/glsl/glsl_types.cpp +++ b/src/glsl/glsl_types.cpp @@ -828,3 +828,31 @@ glsl_type::std140_size(bool row_major) const assert(!"not reached"); return -1; } + + +unsigned +glsl_type::count_attribute_slots() const +{ + /* From page 31 (page 37 of the PDF) of the GLSL 1.50 spec: + * + * "A scalar input counts the same amount against this limit as a vec4, + * so applications may want to consider packing groups of four + * unrelated float inputs together into a vector to better utilize the + * capabilities of the underlying hardware. A matrix input will use up + * multiple locations. The number of locations used will equal the + * number of columns in the matrix." + * + * The spec does not explicitly say how arrays are counted. However, it + * should be safe to assume the total number of slots consumed by an array + * is the number of entries in the array multiplied by the number of slots + * consumed by a single element of the array. + */ + + if (this->is_array()) + return this->array_size() * this->element_type()->count_attribute_slots(); + + if (this->is_matrix()) + return this->matrix_columns; + + return 1; +} |