diff options
| author | Neil Roberts <nroberts@igalia.com> | 2018-01-25 19:15:41 +0100 |
|---|---|---|
| committer | Ian Romanick <ian.d.romanick@intel.com> | 2018-04-19 15:57:45 -0700 |
| commit | c4f30a9100bfba7800162bdef267743a2419ec19 (patch) | |
| tree | 876a7bb8b042cdee72951a051d8589065fa86e81 /src/compiler/spirv/vtn_variables.c | |
| parent | c32e1035cb4f1e0c2c1bd45611e3a35e7caf57b6 (diff) | |
spirv: Lower BaseVertex to FIRST_VERTEX instead of BASE_VERTEX
The base vertex in Vulkan is different from GL in that for non-indexed
primitives the value is taken from the firstVertex parameter instead
of being set to zero. This coincides with the new SYSTEM_VALUE_FIRST_VERTEX
instead of BASE_VERTEX.
v2 (idr): Add comment describing why SYSTEM_VALUE_FIRST_VERTEX is used
for SpvBuiltInBaseVertex. Suggested by Jason.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com> [v1]
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Diffstat (limited to 'src/compiler/spirv/vtn_variables.c')
| -rw-r--r-- | src/compiler/spirv/vtn_variables.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/src/compiler/spirv/vtn_variables.c b/src/compiler/spirv/vtn_variables.c index 0673fe8067..9679ff6526 100644 --- a/src/compiler/spirv/vtn_variables.c +++ b/src/compiler/spirv/vtn_variables.c @@ -1296,7 +1296,10 @@ vtn_get_builtin_location(struct vtn_builder *b, set_mode_system_value(b, mode); break; case SpvBuiltInBaseVertex: - *location = SYSTEM_VALUE_BASE_VERTEX; + /* OpenGL gl_BaseVertex (SYSTEM_VALUE_BASE_VERTEX) is not the same + * semantic as SPIR-V BaseVertex (SYSTEM_VALUE_FIRST_VERTEX). + */ + *location = SYSTEM_VALUE_FIRST_VERTEX; set_mode_system_value(b, mode); break; case SpvBuiltInBaseInstance: |