From 65c664560c244da9a5da650c61b8dbe5a323c2ba Mon Sep 17 00:00:00 2001
From: Subv <subv2112@gmail.com>
Date: Mon, 2 Jul 2018 21:02:46 -0500
Subject: [PATCH 1/2] GPU: Don't try to parse the depth test function if the
 depth test is disabled.

---
 src/video_core/renderer_opengl/gl_rasterizer.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/video_core/renderer_opengl/gl_rasterizer.cpp b/src/video_core/renderer_opengl/gl_rasterizer.cpp
index ca3814cfc..1ced31e84 100644
--- a/src/video_core/renderer_opengl/gl_rasterizer.cpp
+++ b/src/video_core/renderer_opengl/gl_rasterizer.cpp
@@ -735,6 +735,10 @@ void RasterizerOpenGL::SyncDepthTestState() {
 
     state.depth.test_enabled = regs.depth_test_enable != 0;
     state.depth.write_mask = regs.depth_write_enabled ? GL_TRUE : GL_FALSE;
+
+    if (!state.depth.test_enabled)
+        return;
+
     state.depth.test_func = MaxwellToGL::ComparisonOp(regs.depth_test_func);
 }
 

From 6e0eba99177e8562e7f4e3ef8709b74a71447a46 Mon Sep 17 00:00:00 2001
From: Subv <subv2112@gmail.com>
Date: Mon, 2 Jul 2018 21:06:36 -0500
Subject: [PATCH 2/2] GPU: Use only the least significant 3 bits when reading
 the depth test func.

Some games set the full GL define value here (including nouveau), but others just seem to set those last 3 bits.
---
 src/video_core/engines/maxwell_3d.h | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/src/video_core/engines/maxwell_3d.h b/src/video_core/engines/maxwell_3d.h
index ff67f2a58..12aec3549 100644
--- a/src/video_core/engines/maxwell_3d.h
+++ b/src/video_core/engines/maxwell_3d.h
@@ -281,14 +281,14 @@ public:
         };
 
         enum class ComparisonOp : u32 {
-            Never = 0x200,
-            Less = 0x201,
-            Equal = 0x202,
-            LessEqual = 0x203,
-            Greater = 0x204,
-            NotEqual = 0x205,
-            GreaterEqual = 0x206,
-            Always = 0x207,
+            Never = 0,
+            Less = 1,
+            Equal = 2,
+            LessEqual = 3,
+            Greater = 4,
+            NotEqual = 5,
+            GreaterEqual = 6,
+            Always = 7,
         };
 
         struct Cull {
@@ -475,7 +475,7 @@ public:
 
                 INSERT_PADDING_WORDS(0x8);
 
-                ComparisonOp depth_test_func;
+                BitField<0, 3, ComparisonOp> depth_test_func;
 
                 INSERT_PADDING_WORDS(0xB);