commit f878d50b65d70c883dd8c882e5096b14e2a9ae53
author Nicolas Capens <capn@google.com> Mon Nov 06 15:29:46 2017 -0500
committer Nicolas Capens <nicolascapens@google.com> Tue Nov 07 21:29:26 2017 +0000
tree b2bacfd0842d80c673fa99ff32153e6e18406d7b
parent 69bffb837b9deecf71447f5406a9dc083c708bc7

Pass down the texture compare state.

Depth format textures can have a comparison operation performed after
their texels have been sampled.

Change-Id: I49f6bb7fab9765265761144ee8b6b62439beb5a3
Reviewed-on: https://swiftshader-review.googlesource.com/5870
Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>

src/Renderer/Sampler.cpp

diff --git a/src/Renderer/Sampler.cpp b/src/Renderer/Sampler.cpp
index 123a1c9..5bf11c8 100644
--- a/src/Renderer/Sampler.cpp
+++ b/src/Renderer/Sampler.cpp
@@ -67,6 +67,8 @@
 		swizzleB = SWIZZLE_BLUE;
 		swizzleA = SWIZZLE_ALPHA;
 
+		compare = COMPARE_BYPASS;
+
 		texture.LOD = 0.0f;
 		exp2LOD = 1.0f;
 
@@ -99,6 +101,7 @@
 			state.swizzleB = swizzleB;
 			state.swizzleA = swizzleA;
 			state.highPrecisionFiltering = highPrecisionFiltering;
+			state.compare = getCompareFunc();
 
 			#if PERF_PROFILE
 				state.compressedFormat = Surface::isCompressed(externalTextureFormat);
@@ -332,6 +335,11 @@
 		this->swizzleA = swizzleA;
 	}
 
+	void Sampler::setCompareFunc(CompareFunc compare)
+	{
+		this->compare = compare;
+	}
+
 	void Sampler::setBaseLevel(int baseLevel)
 	{
 		texture.baseLevel = baseLevel;
@@ -478,4 +486,19 @@
 
 		return addressingModeW;
 	}
+
+	CompareFunc Sampler::getCompareFunc() const
+	{
+		if(getTextureFilter() == FILTER_GATHER)
+		{
+			return COMPARE_BYPASS;
+		}
+
+		if(internalTextureFormat == FORMAT_D32FS8_SHADOW)
+		{
+			return COMPARE_LESSEQUAL;
+		}
+
+		return compare;
+	}
 }