diff options
| author | Neil Roberts <nroberts@igalia.com> | 2017-10-30 13:22:49 +0100 |
|---|---|---|
| committer | Andres Gomez <agomez@igalia.com> | 2017-11-21 18:16:45 +0200 |
| commit | 3ca2b0079906f591498c32fde97ed91ade08ff74 (patch) | |
| tree | 7d7e6c0b0c07b777f0fe8c24ad3a3e305524aac0 | |
| parent | 731076f0fd45e21fe1328e53828deb2071d77168 (diff) | |
| download | mesa-3ca2b0079906f591498c32fde97ed91ade08ff74.tar.gz | |
glsl: Transform fb buffers are only active if a variable uses them
The GL spec will soon be revised to clarify that a buffer binding for
a transform feedback buffer is only required if a variable is actually
defined to use the buffer binding point. Previously a declaration for
the default transform buffer would make it require a binding even if
nothing was declared to use the default buffer.
Affects:
KHR-GL44/45.enhanced_layouts.xfb_stride_of_empty_list
KHR-GL44/45.enhanced_layouts.xfb_stride_of_empty_list_and_api
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
Cc: mesa-stable@lists.freedesktop.org
(cherry picked from commit 4dc8458cd13154daa48bd97c3f8393daf02aa351)
| -rw-r--r-- | src/compiler/glsl/link_varyings.cpp | 24 |
1 files changed, 15 insertions, 9 deletions
diff --git a/src/compiler/glsl/link_varyings.cpp b/src/compiler/glsl/link_varyings.cpp index 17d556013f4..0593588f1bf 100644 --- a/src/compiler/glsl/link_varyings.cpp +++ b/src/compiler/glsl/link_varyings.cpp @@ -1119,7 +1119,6 @@ store_tfeedback_info(struct gl_context *ctx, struct gl_shader_program *prog, if (has_xfb_qualifiers) { for (unsigned j = 0; j < MAX_FEEDBACK_BUFFERS; j++) { if (prog->TransformFeedback.BufferStride[j]) { - buffers |= 1 << j; explicit_stride[j] = true; xfb_prog->sh.LinkedTransformFeedback->Buffers[j].Stride = prog->TransformFeedback.BufferStride[j] / 4; @@ -1144,10 +1143,24 @@ store_tfeedback_info(struct gl_context *ctx, struct gl_shader_program *prog, num_buffers++; buffer_stream_id = -1; continue; - } else if (tfeedback_decls[i].is_varying()) { + } + + if (has_xfb_qualifiers) { + buffer = tfeedback_decls[i].get_buffer(); + } else { + buffer = num_buffers; + } + + if (tfeedback_decls[i].is_varying()) { if (buffer_stream_id == -1) { /* First varying writing to this buffer: remember its stream */ buffer_stream_id = (int) tfeedback_decls[i].get_stream_id(); + + /* Only mark a buffer as active when there is a varying + * attached to it. This behaviour is based on a revised version + * of section 13.2.2 of the GL 4.6 spec. + */ + buffers |= 1 << buffer; } else if (buffer_stream_id != (int) tfeedback_decls[i].get_stream_id()) { /* Varying writes to the same buffer from a different stream */ @@ -1163,13 +1176,6 @@ store_tfeedback_info(struct gl_context *ctx, struct gl_shader_program *prog, } } - if (has_xfb_qualifiers) { - buffer = tfeedback_decls[i].get_buffer(); - } else { - buffer = num_buffers; - } - buffers |= 1 << buffer; - if (!tfeedback_decls[i].store(ctx, prog, xfb_prog->sh.LinkedTransformFeedback, buffer, num_buffers, num_outputs, |