Implement seamless cubemap sampling. The addressing is offset by 1 to account for the border. Note that this could be avoided by locking at (0, 0) instead of (-1, -1) instead, but then negative address offsets have to be allowed and this complicates the subsequent calculations and only unsigned extension from 32-bit to 64-bit is typically for free during memory accesses. Change-Id: I5fb843401d440a9d77d141782124a9c260765830 Reviewed-on: https://swiftshader-review.googlesource.com/13289 Tested-by: Nicolas Capens <nicolascapens@google.com> Reviewed-by: Alexis Hétu <sugoi@google.com> Reviewed-by: Nicolas Capens <nicolascapens@google.com>

diff --git a/src/Renderer/Sampler.cpp b/src/Renderer/Sampler.cpp
index 71a6eaf..5862996 100644
--- a/src/Renderer/Sampler.cpp
+++ b/src/Renderer/Sampler.cpp

@@ -61,6 +61,7 @@
 		sRGB = false;
 		gather = false;
 		highPrecisionFiltering = false;
+		border = 0;
 
 		swizzleR = SWIZZLE_RED;
 		swizzleG = SWIZZLE_GREEN;
@@ -117,7 +118,8 @@
 		{
 			Mipmap &mipmap = texture.mipmap[level];
 
-			mipmap.buffer[face] = surface->lockInternal(0, 0, 0, LOCK_UNLOCKED, PRIVATE);
+			border = surface->getBorder();
+			mipmap.buffer[face] = surface->lockInternal(-border, -border, 0, LOCK_UNLOCKED, PRIVATE);
 
 			if(face == 0)
 			{
@@ -456,7 +458,7 @@
 	{
 		if(textureType == TEXTURE_CUBE)
 		{
-			return ADDRESSING_CLAMP;
+			return border ? ADDRESSING_SEAMLESS : ADDRESSING_CLAMP;
 		}
 
 		return addressingModeU;
@@ -466,7 +468,7 @@
 	{
 		if(textureType == TEXTURE_CUBE)
 		{
-			return ADDRESSING_CLAMP;
+			return border ? ADDRESSING_SEAMLESS : ADDRESSING_CLAMP;
 		}
 
 		return addressingModeV;

diff --git a/src/Renderer/Sampler.hpp b/src/Renderer/Sampler.hpp
index ad2145c..9918acf 100644
--- a/src/Renderer/Sampler.hpp
+++ b/src/Renderer/Sampler.hpp

@@ -103,7 +103,8 @@
 		ADDRESSING_CLAMP,
 		ADDRESSING_MIRROR,
 		ADDRESSING_MIRRORONCE,
-		ADDRESSING_BORDER,
+		ADDRESSING_BORDER,     // Single color
+		ADDRESSING_SEAMLESS,   // Border of pixels
 		ADDRESSING_LAYER,
 		ADDRESSING_TEXELFETCH,
 
@@ -224,6 +225,7 @@
 		bool sRGB;
 		bool gather;
 		bool highPrecisionFiltering;
+		int border;
 
 		SwizzleType swizzleR;
 		SwizzleType swizzleG;