Introduce "Compatibility Flags".

These should be used very restrictively, see comment in Compatibility.h.

Should help #8004, by disabling depth rounding in Fight Night round 3.

CMakeLists.txt

@@ -1132,6 +1132,8 @@ add_library(${CoreLibName} ${CoreLinkType}
 	Core/Config.h
 	Core/Core.cpp
 	Core/Core.h
+	Core/Compatibility.cpp
+	Core/Compatibility.h
 	Core/CoreParameter.h
 	Core/CoreTiming.cpp
 	Core/CoreTiming.h

Core/Compatibility.cpp

@@ -0,0 +1,43 @@
+// Copyright (c) 2013- PPSSPP Project.
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, version 2.0 or later versions.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License 2.0 for more details.
+
+// A copy of the GPL 2.0 should have been included with the program.
+// If not, see http://www.gnu.org/licenses/
+
+// Official git repository and contact information can be found at
+// https://github.com/hrydgard/ppsspp and http://www.ppsspp.org/.
+
+#include "file/ini_file.h"
+#include "Core/Compatibility.h"
+#include "Core/System.h"
+
+void Compatibility::Load(const std::string &gameID) {
+	IniFile compat;
+	Clear();
+
+	std::string path = GetSysDirectory(DIRECTORY_SYSTEM) + "compat.ini";
+	if (compat.Load(path)) {
+		LoadIniSection(compat, gameID);
+	}
+
+	// This loads from assets.
+	if (compat.LoadFromVFS("compat.ini")) {
+		LoadIniSection(compat, gameID);
+	}
+}
+
+void Compatibility::Clear() {
+	memset(&flags_, 0, sizeof(flags_));
+}
+
+void Compatibility::LoadIniSection(IniFile &iniFile, std::string section) {
+	iniFile.Get(section.c_str(), "NoDepthRounding", &flags_.NoDepthRounding, flags_.NoDepthRounding);
+}

Core/Compatibility.h

@@ -0,0 +1,70 @@
+// Copyright (c) 2015- PPSSPP Project.
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, version 2.0 or later versions.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License 2.0 for more details.
+
+// A copy of the GPL 2.0 should have been included with the program.
+// If not, see http://www.gnu.org/licenses/
+
+// Official git repository and contact information can be found at
+// https://github.com/hrydgard/ppsspp and http://www.ppsspp.org/.
+
+#pragma once
+
+#include <string>
+#include <stdint.h>
+
+// Compatibility flags are controlled by assets/compat.ini.
+// Alternatively, if PSP/SYSTEM/compat.ini exists, it is merged on top, to enable editing
+// the file on Android for tests.
+//
+// This file is not meant to be user-editable, although is kept as a separate ini
+// file instead of compiled into the code for debugging purposes.
+//
+// The uses cases are strict:
+//   * Enable fixes for things we can't reasonably emulate without completely ruining
+//     performance for other games, such as the screen copies in Dangan Ronpa
+//   * Disabling accuracy features like 16-bit depth rounding, when we can't seem to
+//     implement them at all in a 100% compatible way
+//   * Emergency game-specific compatibility fixes before releases, such as the GTA
+//     music problem where every attempted fix has reduced compatibility with other games
+//   * Enable "unsafe" performance optimizations that some games can tolerate and
+//     others cannot. We do not currently have any of those.
+//
+// This functionality should NOT be used for any of the following:
+//   * Cheats
+//   * Fun hacks, like enlarged heads or whatever
+//   * Fixing general compatibility issues. First try to find a general solution. Try hard.
+//
+// We already have the Action Replay-based cheat system for such use cases.
+
+struct CompatFlags {
+	bool NoDepthRounding;
+	// GTAMusicFix, ...
+};
+
+class IniFile;
+
+class Compatibility {
+public:
+	Compatibility() {
+		Clear();
+	}
+
+	// Flags enforced read-only through const. Only way to change them is to load assets/compat.ini.
+	const CompatFlags &flags() const { return flags_; }
+
+	void Load(const std::string &gameID);
+
+private:
+	void Clear();
+	void LoadIniSection(IniFile &iniFile, std::string section);
+
+	CompatFlags flags_;
+};

Core/Core.vcxproj

@@ -179,6 +179,7 @@
     <ClCompile Include="..\ext\udis86\syn-intel.c" />
     <ClCompile Include="..\ext\udis86\syn.c" />
     <ClCompile Include="..\ext\udis86\udis86.c" />
+    <ClCompile Include="Compatibility.cpp" />
     <ClCompile Include="Config.cpp" />
     <ClCompile Include="Core.cpp" />
     <ClCompile Include="CoreTiming.cpp" />
@@ -501,6 +502,7 @@
     <ClInclude Include="..\ext\udis86\types.h" />
     <ClInclude Include="..\ext\udis86\udint.h" />
     <ClInclude Include="..\ext\udis86\udis86.h" />
+    <ClInclude Include="Compatibility.h" />
     <ClInclude Include="Config.h" />
     <ClInclude Include="Core.h" />
     <ClInclude Include="CoreParameter.h" />

Core/Core.vcxproj.filters

@@ -622,6 +622,9 @@
     <ClCompile Include="FileLoaders\DiskCachingFileLoader.cpp">
       <Filter>FileLoaders</Filter>
     </ClCompile>
+    <ClCompile Include="Compatibility.cpp">
+      <Filter>Core</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="ELF\ElfReader.h">
@@ -1167,6 +1170,9 @@
     <ClInclude Include="HLE\ThreadQueueList.h">
       <Filter>HLE</Filter>
     </ClInclude>
+    <ClInclude Include="Compatibility.h">
+      <Filter>Core</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <None Include="CMakeLists.txt" />

Core/CoreParameter.h

@@ -19,6 +19,8 @@
 
 #include <string>
 
+#include "Core/Compatibility.h"
+
 enum CPUCore {
 	CPU_INTERPRETER,
 	CPU_JIT,
@@ -69,4 +71,6 @@ struct CoreParameter {
 	bool frozen;
 
 	FileLoader *mountIsoLoader;
+
+	Compatibility compat;
 };

Core/HLE/sceKernelThread.cpp

@@ -1237,7 +1237,7 @@ u32 sceKernelReferThreadStatus(u32 threadID, u32 statusPtr)
 			return SCE_KERNEL_ERROR_ILLEGAL_SIZE;
 		}
 
-		DEBUG_LOG(SCEKERNEL, "sceKernelReferThreadStatus(%i, %08x)", threadID, statusPtr);
+		VERBOSE_LOG(SCEKERNEL, "sceKernelReferThreadStatus(%i, %08x)", threadID, statusPtr);
 
 		t->nt.nativeSize = THREADINFO_SIZE_AFTER_260;
 		if (wantedSize != 0)
@@ -1248,7 +1248,7 @@ u32 sceKernelReferThreadStatus(u32 threadID, u32 statusPtr)
 	}
 	else
 	{
-		DEBUG_LOG(SCEKERNEL, "sceKernelReferThreadStatus(%i, %08x)", threadID, statusPtr);
+		VERBOSE_LOG(SCEKERNEL, "sceKernelReferThreadStatus(%i, %08x)", threadID, statusPtr);
 
 		t->nt.nativeSize = THREADINFO_SIZE;
 		u32 sz = std::min(THREADINFO_SIZE, wantedSize);

Core/MemMap.h

@@ -276,7 +276,6 @@ inline void MemcpyUnchecked(const u32 to_address, const u32 from_address, const
 	MemcpyUnchecked(GetPointer(to_address), from_address, len);
 }
 
-// TODO: This considers 0x88900000 a valid address. Probably not good.
 inline bool IsValidAddress(const u32 address) {
 	if ((address & 0x3E000000) == 0x08000000) {
 		return true;

Core/System.cpp

@@ -204,6 +204,11 @@ void CPU_Init() {
 		break;
 	}
 
+	// Here we have read the PARAM.SFO, let's see if we need any compatibility overrides.
+	std::string discID = g_paramSFO.GetValueString("DISC_ID");
+	if (!discID.empty())
+		coreParameter.compat.Load(discID);
+
 	Memory::Init();
 	mipsr4k.Reset();
 

GPU/Directx9/GPU_DX9.cpp

@@ -466,6 +466,17 @@ void DIRECTX9_GPU::UpdateCmdInfo() {
 		cmdInfo_[GE_CMD_VERTEXTYPE].flags |= FLAG_FLUSHBEFOREONCHANGE;
 		cmdInfo_[GE_CMD_VERTEXTYPE].func = &DIRECTX9_GPU::Execute_VertexType;
 	}
+
+	u32 features = 0;
+
+	// Set some flags that may be convenient in the future if we merge the backends more.
+	features |= GPU_SUPPORTS_BLEND_MINMAX;
+	features |= GPU_SUPPORTS_TEXTURE_LOD_CONTROL;
+
+	if (!PSP_CoreParameter().compat.flags().NoDepthRounding)
+		features |= GPU_ROUND_DEPTH_TO_16BIT;
+
+	gstate_c.featureFlags = features;
 }
 
 DIRECTX9_GPU::~DIRECTX9_GPU() {

GPU/Directx9/VertexShaderGeneratorDX9.cpp

@@ -226,7 +226,7 @@ void GenerateVertexShaderDX9(int prim, char *buffer, bool useHWTransform) {
 		}
 	}
 
-	if (!gstate.isModeThrough()) {
+	if (!gstate.isModeThrough() && gstate_c.Supports(GPU_ROUND_DEPTH_TO_16BIT)) {
 		WRITE(p, "float4 u_depthRange : register(c%i);\n", CONST_VS_DEPTHRANGE);
 	}
 
@@ -286,7 +286,7 @@ void GenerateVertexShaderDX9(int prim, char *buffer, bool useHWTransform) {
 
 	// Confirmed: Through mode gets through exactly the same in GL and D3D in Phantasy Star: Text is 38023.0 in the test scene.
 
-	if (!gstate.isModeThrough()) {
+	if (!gstate.isModeThrough() && gstate_c.Supports(GPU_ROUND_DEPTH_TO_16BIT)) {
 		// Apply the projection and viewport to get the Z buffer value, floor to integer, undo the viewport and projection.
 		// The Z range in D3D is different but we compensate for that using parameters.
 		WRITE(p, "\nfloat4 depthRoundZVP(float4 v) {\n");
@@ -328,7 +328,11 @@ void GenerateVertexShaderDX9(int prim, char *buffer, bool useHWTransform) {
 		if (gstate.isModeThrough())	{
 			WRITE(p, "  Out.gl_Position = mul(float4(In.position.xyz, 1.0), u_proj_through);\n");
 		} else {
-			WRITE(p, "  Out.gl_Position = depthRoundZVP(mul(float4(In.position.xyz, 1.0), u_proj));\n");
+			if (gstate_c.Supports(GPU_ROUND_DEPTH_TO_16BIT)) {
+				WRITE(p, "  Out.gl_Position = depthRoundZVP(mul(float4(In.position.xyz, 1.0), u_proj));\n");
+			} else {
+				WRITE(p, "  Out.gl_Position = mul(float4(In.position.xyz, 1.0), u_proj);\n");
+			}
 		}
 	}  else {
 		// Step 1: World Transform / Skinning
@@ -417,7 +421,11 @@ void GenerateVertexShaderDX9(int prim, char *buffer, bool useHWTransform) {
 		WRITE(p, "  float4 viewPos = float4(mul(float4(worldpos, 1.0), u_view), 1.0);\n");
 
 		// Final view and projection transforms.
-		WRITE(p, "  Out.gl_Position = depthRoundZVP(mul(viewPos, u_proj));\n");
+		if (gstate_c.Supports(GPU_ROUND_DEPTH_TO_16BIT)) {
+			WRITE(p, "  Out.gl_Position = depthRoundZVP(mul(viewPos, u_proj));\n");
+		} else {
+			WRITE(p, "  Out.gl_Position = mul(viewPos, u_proj);\n");
+		}
 
 		// TODO: Declare variables for dots for shade mapping if needed.
 

GPU/GLES/GLES_GPU.cpp

@@ -558,9 +558,13 @@ void GLES_GPU::CheckGPUFeatures() {
 	if (!gl_extensions.IsGLES)
 		features |= GPU_SUPPORTS_LOGIC_OP;
 
-	if (gl_extensions.GLES3 || !gl_extensions.IsGLES) {
+	if (gl_extensions.GLES3 || !gl_extensions.IsGLES)
 		features |= GPU_SUPPORTS_TEXTURE_LOD_CONTROL;
-	}
+
+	// In the future, also disable this when we get a proper 16-bit depth buffer.
+	if (!PSP_CoreParameter().compat.flags().NoDepthRounding)
+		features |= GPU_ROUND_DEPTH_TO_16BIT;
+
 
 #ifdef MOBILE_DEVICE
 	// Arguably, we should turn off GPU_IS_MOBILE on like modern Tegras, etc.

GPU/GLES/VertexShaderGenerator.cpp

@@ -354,7 +354,7 @@ void GenerateVertexShader(int prim, u32 vertType, char *buffer, bool useHWTransf
 		WRITE(p, "uniform highp vec2 u_fogcoef;\n");
 	}
 
-	if (!gstate.isModeThrough()) {
+	if (!gstate.isModeThrough() && gstate_c.Supports(GPU_ROUND_DEPTH_TO_16BIT)) {
 		WRITE(p, "uniform highp vec4 u_depthRange;\n");
 	}
 
@@ -380,7 +380,7 @@ void GenerateVertexShader(int prim, u32 vertType, char *buffer, bool useHWTransf
 	}
 
 	// See comment above this function (GenerateVertexShader).
-	if (!gstate.isModeThrough()) {
+	if (!gstate.isModeThrough() && gstate_c.Supports(GPU_ROUND_DEPTH_TO_16BIT)) {
 		// Apply the projection and viewport to get the Z buffer value, floor to integer, undo the viewport and projection.
 		WRITE(p, "\nvec4 depthRoundZVP(vec4 v) {\n");
 		WRITE(p, "  float z = v.z / v.w;\n");
@@ -418,7 +418,11 @@ void GenerateVertexShader(int prim, u32 vertType, char *buffer, bool useHWTransf
 			WRITE(p, "  gl_Position = u_proj_through * vec4(position.xyz, 1.0);\n");
 		} else {
 			// The viewport is used in this case, so need to compensate for that.
-			WRITE(p, "  gl_Position = depthRoundZVP(u_proj * vec4(position.xyz, 1.0));\n");
+			if (gstate_c.Supports(GPU_ROUND_DEPTH_TO_16BIT)) {
+				WRITE(p, "  gl_Position = depthRoundZVP(u_proj * vec4(position.xyz, 1.0));\n");
+			} else {
+				WRITE(p, "  gl_Position = u_proj * vec4(position.xyz, 1.0);\n");
+			}
 		}
 	} else {
 		// Step 1: World Transform / Skinning
@@ -511,7 +515,11 @@ void GenerateVertexShader(int prim, u32 vertType, char *buffer, bool useHWTransf
 		WRITE(p, "  vec4 viewPos = u_view * vec4(worldpos, 1.0);\n");
 
 		// Final view and projection transforms.
-		WRITE(p, "  gl_Position = depthRoundZVP(u_proj * viewPos);\n");
+		if (gstate_c.Supports(GPU_ROUND_DEPTH_TO_16BIT)) {
+			WRITE(p, "  gl_Position = depthRoundZVP(u_proj * viewPos);\n");
+		} else {
+			WRITE(p, "  gl_Position = u_proj * viewPos;\n");
+		}
 
 		// TODO: Declare variables for dots for shade mapping if needed.
 

GPU/GPUState.h

@@ -454,6 +454,7 @@ enum {
 	GPU_SUPPORTS_BLEND_MINMAX = FLAG_BIT(4),
 	GPU_SUPPORTS_LOGIC_OP = FLAG_BIT(5),
 	GPU_SUPPORTS_ANY_FRAMEBUFFER_FETCH = FLAG_BIT(20),
+	GPU_ROUND_DEPTH_TO_16BIT = FLAG_BIT(23),  // Can be disabled either per game or if we use a real 16-bit depth buffer
 	GPU_SUPPORTS_TEXTURE_LOD_CONTROL = FLAG_BIT(24),
 	GPU_SUPPORTS_FBO = FLAG_BIT(25),
 	GPU_SUPPORTS_ARB_FRAMEBUFFER_BLIT = FLAG_BIT(26),

android/jni/Android.mk

@@ -199,6 +199,7 @@ EXEC_AND_LIB_FILES := \
   $(SRC)/Core/HW/SasAudio.cpp.arm \
   $(SRC)/Core/HW/StereoResampler.cpp.arm \
   $(SRC)/Core/Core.cpp \
+  $(SRC)/Core/Compatibility.cpp \
   $(SRC)/Core/Config.cpp \
   $(SRC)/Core/CoreTiming.cpp \
   $(SRC)/Core/CwCheat.cpp \

assets/compat.ini

@@ -0,0 +1,5 @@
+# Fight Night Round 3
+[ULES00270]
+NoDepthRounding = true
+[ULUS10066]
+NoDepthRounding = true