From 16d3dbc5ea04ea1bd05f32b7041bfb2f6d6e876d Mon Sep 17 00:00:00 2001
From: Tony Wasserka <NeoBrainX@gmail.com>
Date: Mon, 21 Apr 2014 22:34:23 +0200
Subject: [PATCH 1/2] BPMemory: Use BitField for the GenMode fields.

---
 Source/Core/VideoCommon/BPMemory.h    | 22 ++++++++++++++--------
 Source/Core/VideoCommon/BPStructs.cpp |  6 +++---
 2 files changed, 17 insertions(+), 11 deletions(-)

diff --git a/Source/Core/VideoCommon/BPMemory.h b/Source/Core/VideoCommon/BPMemory.h
index 5332c3e8d4..09f0efbaf7 100644
--- a/Source/Core/VideoCommon/BPMemory.h
+++ b/Source/Core/VideoCommon/BPMemory.h
@@ -531,16 +531,22 @@ struct FourTexUnits
 
 union GenMode
 {
-	struct
+	enum CullMode : u32
 	{
-		u32 numtexgens    : 4; //     0xF
-		u32 numcolchans   : 5; //   0x1E0
-		u32 multisampling : 1; //   0x200
-		u32 numtevstages  : 4; //  0x3C00
-		u32 cullmode      : 2; //  0xC000
-		u32 numindstages  : 3; // 0x30000
-		u32 zfreeze       : 5; //0x3C0000
+		CULL_NONE = 0,
+		CULL_BACK = 1, // cull back-facing primitives
+		CULL_FRONT = 2, // cull front-facing primitives
+		CULL_ALL = 3, // cull all primitives
 	};
+
+	BitField< 0,4,u32> numtexgens;
+	BitField< 4,5,u32> numcolchans;
+	BitField< 9,1,u32> multisampling;
+	BitField<10,4,u32> numtevstages;
+	BitField<14,2,CullMode> cullmode;
+	BitField<16,3,u32> numindstages;
+	BitField<19,5,u32> zfreeze;
+
 	u32 hex;
 };
 
diff --git a/Source/Core/VideoCommon/BPStructs.cpp b/Source/Core/VideoCommon/BPStructs.cpp
index 8b904a95f8..d3caaf49d3 100644
--- a/Source/Core/VideoCommon/BPStructs.cpp
+++ b/Source/Core/VideoCommon/BPStructs.cpp
@@ -91,9 +91,9 @@ void BPWritten(const BPCmd& bp)
 	case BPMEM_GENMODE: // Set the Generation Mode
 		{
 			PRIM_LOG("genmode: texgen=%d, col=%d, multisampling=%d, tev=%d, cullmode=%d, ind=%d, zfeeze=%d",
-			         bpmem.genMode.numtexgens, bpmem.genMode.numcolchans,
-			         bpmem.genMode.multisampling, bpmem.genMode.numtevstages+1, bpmem.genMode.cullmode,
-			         bpmem.genMode.numindstages, bpmem.genMode.zfreeze);
+			         (u32)bpmem.genMode.numtexgens, (u32)bpmem.genMode.numcolchans,
+			         (u32)bpmem.genMode.multisampling, (u32)bpmem.genMode.numtevstages+1, (u32)bpmem.genMode.cullmode,
+			         (u32)bpmem.genMode.numindstages, (u32)bpmem.genMode.zfreeze);
 
 			// Only call SetGenerationMode when cull mode changes.
 			if (bp.changes & 0xC000)

From 762572a08ce17a83a5c5b2c2b968c92778f7221b Mon Sep 17 00:00:00 2001
From: Tony Wasserka <NeoBrainX@gmail.com>
Date: Mon, 21 Apr 2014 22:38:08 +0200
Subject: [PATCH 2/2] BPMemory: Fix GenMode using an incorrect number of bits
 for the number of color chans.

---
 Source/Core/VideoCommon/BPMemory.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Source/Core/VideoCommon/BPMemory.h b/Source/Core/VideoCommon/BPMemory.h
index 09f0efbaf7..a615f5d3a7 100644
--- a/Source/Core/VideoCommon/BPMemory.h
+++ b/Source/Core/VideoCommon/BPMemory.h
@@ -540,7 +540,9 @@ union GenMode
 	};
 
 	BitField< 0,4,u32> numtexgens;
-	BitField< 4,5,u32> numcolchans;
+	BitField< 4,3,u32> numcolchans;
+	// 1 bit unused?
+	BitField< 8,1,u32> flat_shading; // unconfirmed
 	BitField< 9,1,u32> multisampling;
 	BitField<10,4,u32> numtevstages;
 	BitField<14,2,CullMode> cullmode;