diff options
| author | Neil Roberts <[email protected]> | 2017-10-30 13:22:49 +0100 |
|---|---|---|
| committer | Neil Roberts <[email protected]> | 2017-11-09 05:39:42 +0100 |
| commit | 4dc8458cd13154daa48bd97c3f8393daf02aa351 (patch) | |
| tree | 82cac611add36b8d0ccf96583423d059f6f2e808 /src/compiler | |
| parent | 951a5dc4cc29da996b54ae63eeba1915a3a65b4a (diff) | |
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 <[email protected]>
Cc: [email protected]
Diffstat (limited to 'src/compiler')
| -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 66a20a2c9b6..e6639306bed 100644 --- a/src/compiler/glsl/link_varyings.cpp +++ b/src/compiler/glsl/link_varyings.cpp @@ -1364,7 +1364,6 @@ 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; @@ -1389,10 +1388,24 @@ 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 */ @@ -1408,13 +1421,6 @@ 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, |