Remove VK support for GL-style symmetric clip space

Change-Id: Idb38063e6d8f7c6345118b2acddba4dcb99d0831
Reviewed-on: https://swiftshader-review.googlesource.com/c/23588
Tested-by: Chris Forbes <chrisforbes@google.com>
Reviewed-by: Corentin Wallez <cwallez@google.com>
Reviewed-by: Chris Forbes <chrisforbes@google.com>
diff --git a/src/Device/Clipper.cpp b/src/Device/Clipper.cpp
index e42c12f..029b93b 100644
--- a/src/Device/Clipper.cpp
+++ b/src/Device/Clipper.cpp
@@ -20,15 +20,6 @@
 
 namespace sw
 {
-	Clipper::Clipper(bool symmetricNormalizedDepth)
-	{
-		n = symmetricNormalizedDepth ? -1.0f : 0.0f;
-	}
-
-	Clipper::~Clipper()
-	{
-	}
-
 	unsigned int Clipper::computeClipFlags(const float4 &v)
 	{
 		return ((v.x > v.w)     ? CLIP_RIGHT  : 0) |
@@ -36,7 +27,7 @@
 		       ((v.z > v.w)     ? CLIP_FAR    : 0) |
 		       ((v.x < -v.w)    ? CLIP_LEFT   : 0) |
 		       ((v.y < -v.w)    ? CLIP_BOTTOM : 0) |
-		       ((v.z < n * v.w) ? CLIP_NEAR   : 0) |
+		       ((v.z < 0)       ? CLIP_NEAR   : 0) |
 		       Clipper::CLIP_FINITE;   // FIXME: xyz finite
 	}
 
@@ -92,8 +83,8 @@
 		{
 			int j = i == polygon.n - 1 ? 0 : i + 1;
 
-			float di = V[i]->z - n * V[i]->w;
-			float dj = V[j]->z - n * V[j]->w;
+			float di = V[i]->z;
+			float dj = V[j]->z;
 
 			if(di >= 0)
 			{