commit 12b00506852b8f8dd472645198117456774e6e5a
author Alexis Hetu <sugoi@google.com> Fri May 20 13:01:11 2016 -0400
committer Nicolas Capens <capn@google.com> Thu Jun 02 15:19:20 2016 +0000
tree 0172e843ee3875dd7c654a110e09d88c89063407
parent e3c87461368a866c819193be299f3a9ddba77946

Implement flat interpolation qualifier support.

By default vertex shader outputs/fragment shader inputs are
smoothly interpolated. The 'flat' keyword can be used to change
the interpolation to "flat", which basically means that no
interpolation is performed. "flat" is the only interpolation
qualifier accepted for integer types.

This change fixes all shaders/precision dEQP tests as well as a
few fragment output integer format types related tests.

Change-Id: Ic64b0ec40c705d885c255b3b671cf7460965dfee
Reviewed-on: https://swiftshader-review.googlesource.com/5390
Tested-by: Nicolas Capens <capn@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>

src/OpenGL/compiler/OutputASM.cpp

diff --git a/src/OpenGL/compiler/OutputASM.cpp b/src/OpenGL/compiler/OutputASM.cpp
index 00af34a..511b91e 100644
--- a/src/OpenGL/compiler/OutputASM.cpp
+++ b/src/OpenGL/compiler/OutputASM.cpp
@@ -2568,6 +2568,12 @@
 		return sw::Shader::PARAMETER_VOID;
 	}
 
+	bool OutputASM::hasFlatQualifier(TIntermTyped *operand)
+	{
+		const TQualifier qualifier = operand->getQualifier();
+		return qualifier == EvqFlat || qualifier == EvqFlatOut || qualifier == EvqFlatIn;
+	}
+
 	unsigned int OutputASM::registerIndex(TIntermTyped *operand)
 	{
 		if(isSamplerRegister(operand))
@@ -2778,10 +2784,12 @@
 				{
 					for(int i = 0; i < varying->totalRegisterCount(); i++)
 					{
-						if(componentCount >= 1) pixelShader->semantic[var + i][0] = sw::Shader::Semantic(sw::Shader::USAGE_COLOR, var + i);
-						if(componentCount >= 2) pixelShader->semantic[var + i][1] = sw::Shader::Semantic(sw::Shader::USAGE_COLOR, var + i);
-						if(componentCount >= 3) pixelShader->semantic[var + i][2] = sw::Shader::Semantic(sw::Shader::USAGE_COLOR, var + i);
-						if(componentCount >= 4) pixelShader->semantic[var + i][3] = sw::Shader::Semantic(sw::Shader::USAGE_COLOR, var + i);
+						bool flat = hasFlatQualifier(varying);
+
+						if(componentCount >= 1) pixelShader->semantic[var + i][0] = sw::Shader::Semantic(sw::Shader::USAGE_COLOR, var + i, flat);
+						if(componentCount >= 2) pixelShader->semantic[var + i][1] = sw::Shader::Semantic(sw::Shader::USAGE_COLOR, var + i, flat);
+						if(componentCount >= 3) pixelShader->semantic[var + i][2] = sw::Shader::Semantic(sw::Shader::USAGE_COLOR, var + i, flat);
+						if(componentCount >= 4) pixelShader->semantic[var + i][3] = sw::Shader::Semantic(sw::Shader::USAGE_COLOR, var + i, flat);
 					}
 				}
 			}