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Commit ec92f3cd by Alexis Hetu Committed by Alexis Hétu
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Transform feedback varyings no longer linked when unused

In OpenGL ES 3.0, varyings declared in the vertex shader may be used by transform feedback, regardless of whether or not they are also declared in the fragment shader. In OpenGL ES 2.0, these unmatched varyings are usually discarded. In order to preserve the OpenGL ES 2.0 behavior and to not burden the Open GL ES 3.0 implementation with new unused varyings, only the unmatched varyings which may be used as transform feedback inputs will be added to the vertex shader, instead of always adding all of them. Change-Id: I35f37b6ee77181b5d3a47605ef246c7d1ecf904d Reviewed-on: https://swiftshader-review.googlesource.com/9808Tested-by: 's avatarAlexis Hétu <sugoi@google.com> Reviewed-by: 's avatarNicolas Capens <capn@google.com>
parent bf7a8145
Showing with 23 additions and 14 deletions
src/OpenGL/libGLESv2/Program.cpp
...@@ -1353,24 +1353,33 @@ namespace es2 ...@@ -1353,24 +1353,33 @@ namespace es2
} }
} }
// For openGL ES 3.0, we need to still add the vertex shader outputs for unmatched varyings, for transform feedback. if(!matched)
if(!matched && (egl::getClientVersion() >= 3))
{ {
int out = output->reg; // For openGL ES 3.0, we need to still add the vertex shader outputs for unmatched varyings, for transform feedback.
int components = VariableRegisterSize(output->type); for(const std::string &indexedTfVaryingName : transformFeedbackVaryings)
int registers = VariableRegisterCount(output->type) * output->size();
if(out >= 0)
{ {
if(out + registers > MAX_VARYING_VECTORS) std::string tfVaryingName = es2::ParseUniformName(indexedTfVaryingName, nullptr);
{
appendToInfoLog("Too many varyings");
return false;
}
for(int i = 0; i < registers; i++) if(tfVaryingName == output->name)
{ {
vertexBinary->setOutput(out + i, components, sw::Shader::Semantic(sw::Shader::USAGE_COLOR)); int out = output->reg;
int components = VariableRegisterSize(output->type);
int registers = VariableRegisterCount(output->type) * output->size();
if(out >= 0)
{
if(out + registers > MAX_VARYING_VECTORS)
{
appendToInfoLog("Too many varyings");
return false;
}
for(int i = 0; i < registers; i++)
{
vertexBinary->setOutput(out + i, components, sw::Shader::Semantic(sw::Shader::USAGE_COLOR));
}
}
break;
} }
} }
} }
......
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