SH-2908 Rework indexed texture rendering to use a uvec4 instead of a float for texture indices in the data stream. Also rework gl_FragColor overrides to not collide with some odd driver implementations.

6 files changed, 153 insertions, 57 deletions

diff --git a/indra/llrender/llgl.cpp b/indra/llrender/llgl.cpp
index 946e602fee..79d4415117 100644
--- a/indra/llrender/llgl.cpp
+++ b/indra/llrender/llgl.cpp
@@ -97,6 +97,8 @@ void APIENTRY gl_debug_callback(GLenum source,
 }
 #endif
 
+void parse_glsl_version(S32& major, S32& minor);
+
 void ll_init_fail_log(std::string filename)
 {
 	gFailLog.open(filename.c_str());
@@ -295,6 +297,7 @@ PFNGLGETACTIVEUNIFORMARBPROC glGetActiveUniformARB = NULL;
 PFNGLGETUNIFORMFVARBPROC glGetUniformfvARB = NULL;
 PFNGLGETUNIFORMIVARBPROC glGetUniformivARB = NULL;
 PFNGLGETSHADERSOURCEARBPROC glGetShaderSourceARB = NULL;
+PFNGLVERTEXATTRIBIPOINTERPROC glVertexAttribIPointer = NULL;
 
 #if LL_WINDOWS
 PFNWGLCREATECONTEXTATTRIBSARBPROC wglCreateContextAttribsARB = NULL;
@@ -341,6 +344,7 @@ PFNGLVERTEXATTRIB4UBVARBPROC glVertexAttrib4ubvARB = NULL;
 PFNGLVERTEXATTRIB4UIVARBPROC glVertexAttrib4uivARB = NULL;
 PFNGLVERTEXATTRIB4USVARBPROC glVertexAttrib4usvARB = NULL;
 PFNGLVERTEXATTRIBPOINTERARBPROC glVertexAttribPointerARB = NULL;
+PFNGLVERTEXATTRIBIPOINTERPROC glVertexAttribIPointer = NULL;
 PFNGLENABLEVERTEXATTRIBARRAYARBPROC glEnableVertexAttribArrayARB = NULL;
 PFNGLDISABLEVERTEXATTRIBARRAYARBPROC glDisableVertexAttribArrayARB = NULL;
 PFNGLPROGRAMSTRINGARBPROC glProgramStringARB = NULL;
@@ -443,7 +447,8 @@ LLGLManager::LLGLManager() :
 	mDriverVersionMinor(0),
 	mDriverVersionRelease(0),
 	mGLVersion(1.0f),
-		
+	mGLSLVersionMajor(0),
+	mGLSLVersionMinor(0),		
 	mVRAM(0),
 	mGLMaxVertexRange(0),
 	mGLMaxIndexRange(0)
@@ -554,6 +559,11 @@ bool LLGLManager::initGL()
 
 	mGLVersion = mDriverVersionMajor + mDriverVersionMinor * .1f;
 
+	if (mGLVersion >= 2.f)
+	{
+		parse_glsl_version(mGLSLVersionMajor, mGLSLVersionMinor);
+	}
+
 	// Trailing space necessary to keep "nVidia Corpor_ati_on" cards
 	// from being recognized as ATI.
 	if (mGLVendor.substr(0,4) == "ATI ")
@@ -1300,6 +1310,7 @@ void LLGLManager::initExtensions()
 		glVertexAttrib4uivARB = (PFNGLVERTEXATTRIB4UIVARBPROC) GLH_EXT_GET_PROC_ADDRESS("glVertexAttrib4uivARB");
 		glVertexAttrib4usvARB = (PFNGLVERTEXATTRIB4USVARBPROC) GLH_EXT_GET_PROC_ADDRESS("glVertexAttrib4usvARB");
 		glVertexAttribPointerARB = (PFNGLVERTEXATTRIBPOINTERARBPROC) GLH_EXT_GET_PROC_ADDRESS("glVertexAttribPointerARB");
+		glVertexAttribIPointer = (PFNGLVERTEXATTRIBIPOINTERPROC) GLH_EXT_GET_PROC_ADDRESS("glVertexAttribIPointer");
 		glEnableVertexAttribArrayARB = (PFNGLENABLEVERTEXATTRIBARRAYARBPROC) GLH_EXT_GET_PROC_ADDRESS("glEnableVertexAttribArrayARB");
 		glDisableVertexAttribArrayARB = (PFNGLDISABLEVERTEXATTRIBARRAYARBPROC) GLH_EXT_GET_PROC_ADDRESS("glDisableVertexAttribArrayARB");
 		glProgramStringARB = (PFNGLPROGRAMSTRINGARBPROC) GLH_EXT_GET_PROC_ADDRESS("glProgramStringARB");
@@ -2098,6 +2109,55 @@ void parse_gl_version( S32* major, S32* minor, S32* release, std::string* vendor
 	}
 }
 
+
+void parse_glsl_version(S32& major, S32& minor)
+{
+	// GL_SHADING_LANGUAGE_VERSION returns a null-terminated string with the format: 
+	// <major>.<minor>[.<release>] [<vendor specific>]
+
+	const char* version = (const char*) glGetString(GL_SHADING_LANGUAGE_VERSION);
+	major = 0;
+	minor = 0;
+	
+	if( !version )
+	{
+		return;
+	}
+
+	std::string ver_copy( version );
+	S32 len = (S32)strlen( version );	/* Flawfinder: ignore */
+	S32 i = 0;
+	S32 start;
+	// Find the major version
+	start = i;
+	for( ; i < len; i++ )
+	{
+		if( '.' == version[i] )
+		{
+			break;
+		}
+	}
+	std::string major_str = ver_copy.substr(start,i-start);
+	LLStringUtil::convertToS32(major_str, major);
+
+	if( '.' == version[i] )
+	{
+		i++;
+	}
+
+	// Find the minor version
+	start = i;
+	for( ; i < len; i++ )
+	{
+		if( ('.' == version[i]) || isspace(version[i]) )
+		{
+			break;
+		}
+	}
+	std::string minor_str = ver_copy.substr(start,i-start);
+	LLStringUtil::convertToS32(minor_str, minor);
+}
+
 LLGLUserClipPlane::LLGLUserClipPlane(const LLPlane& p, const glh::matrix4f& modelview, const glh::matrix4f& projection, bool apply)
 {
 	mApply = apply;
diff --git a/indra/llrender/llgl.h b/indra/llrender/llgl.h
index 6a147b8e19..5a33c98708 100644
--- a/indra/llrender/llgl.h
+++ b/indra/llrender/llgl.h
@@ -138,6 +138,8 @@ public:
 	S32 mDriverVersionMinor;
 	S32 mDriverVersionRelease;
 	F32 mGLVersion; // e.g = 1.4
+	S32 mGLSLVersionMajor;
+	S32 mGLSLVersionMinor;
 	std::string mDriverVersionVendorString;
 
 	S32 mVRAM; // VRAM in MB
diff --git a/indra/llrender/llglheaders.h b/indra/llrender/llglheaders.h
index 10aad202e1..d61ec707f0 100644
--- a/indra/llrender/llglheaders.h
+++ b/indra/llrender/llglheaders.h
@@ -199,6 +199,7 @@ extern PFNGLVERTEXATTRIB4UBVARBPROC glVertexAttrib4ubvARB;
 extern PFNGLVERTEXATTRIB4UIVARBPROC glVertexAttrib4uivARB;
 extern PFNGLVERTEXATTRIB4USVARBPROC glVertexAttrib4usvARB;
 extern PFNGLVERTEXATTRIBPOINTERARBPROC glVertexAttribPointerARB;
+extern PFNGLVERTEXATTRIBIPOINTERPROC glVertexAttribIPointer;
 extern PFNGLENABLEVERTEXATTRIBARRAYARBPROC glEnableVertexAttribArrayARB;
 extern PFNGLDISABLEVERTEXATTRIBARRAYARBPROC glDisableVertexAttribArrayARB;
 extern PFNGLPROGRAMSTRINGARBPROC glProgramStringARB;
@@ -460,6 +461,7 @@ extern PFNGLVERTEXATTRIB4UBVARBPROC glVertexAttrib4ubvARB;
 extern PFNGLVERTEXATTRIB4UIVARBPROC glVertexAttrib4uivARB;
 extern PFNGLVERTEXATTRIB4USVARBPROC glVertexAttrib4usvARB;
 extern PFNGLVERTEXATTRIBPOINTERARBPROC glVertexAttribPointerARB;
+extern PFNGLVERTEXATTRIBIPOINTERPROC glVertexAttribIPointer;
 extern PFNGLENABLEVERTEXATTRIBARRAYARBPROC glEnableVertexAttribArrayARB;
 extern PFNGLDISABLEVERTEXATTRIBARRAYARBPROC glDisableVertexAttribArrayARB;
 extern PFNGLPROGRAMSTRINGARBPROC glProgramStringARB;
@@ -693,6 +695,7 @@ extern PFNGLVERTEXATTRIB4UBVARBPROC glVertexAttrib4ubvARB;
 extern PFNGLVERTEXATTRIB4UIVARBPROC glVertexAttrib4uivARB;
 extern PFNGLVERTEXATTRIB4USVARBPROC glVertexAttrib4usvARB;
 extern PFNGLVERTEXATTRIBPOINTERARBPROC glVertexAttribPointerARB;
+extern PFNGLVERTEXATTRIBIPOINTERPROC glVertexAttribIPointer;
 extern PFNGLENABLEVERTEXATTRIBARRAYARBPROC glEnableVertexAttribArrayARB;
 extern PFNGLDISABLEVERTEXATTRIBARRAYARBPROC glDisableVertexAttribArrayARB;
 extern PFNGLPROGRAMSTRINGARBPROC glProgramStringARB;
diff --git a/indra/llrender/llglslshader.cpp b/indra/llrender/llglslshader.cpp
index 7eba62e59e..a879a18895 100644
--- a/indra/llrender/llglslshader.cpp
+++ b/indra/llrender/llglslshader.cpp
@@ -164,8 +164,9 @@ BOOL LLGLSLShader::createShader(vector<string> * attributes,
 		return FALSE;
 	}
 
-	if (gGLManager.mGLVersion < 3.1f)
-	{ //attachShaderFeatures may have set the number of indexed texture channels, so set to 1 again
+	if (gGLManager.mGLSLVersionMajor < 2 && gGLManager.mGLSLVersionMinor < 3)
+	{ //indexed texture rendering requires GLSL 1.3 or later
+		//attachShaderFeatures may have set the number of indexed texture channels, so set to 1 again
 		mFeatures.mIndexedTextureChannels = llmin(mFeatures.mIndexedTextureChannels, 1);
 	}
 
diff --git a/indra/llrender/llshadermgr.cpp b/indra/llrender/llshadermgr.cpp
index d03d349f0f..321b139181 100644
--- a/indra/llrender/llshadermgr.cpp
+++ b/indra/llrender/llshadermgr.cpp
@@ -575,31 +575,39 @@ GLhandleARB LLShaderMgr::loadShaderFile(const std::string& filename, S32 & shade
 	GLcharARB* text[4096];
 	GLuint count = 0;
 
-	F32 version = gGLManager.mGLVersion;
-
-//hack to never use GLSL > 1.20 on OSX
-#if LL_DARWIN
-	version = llmin(version, 2.9f);
-#endif
-
-	if (version < 2.1f)
-	{
-		text[count++] = strdup("#version 110\n");
-		text[count++] = strdup("#define ATTRIBUTE attribute\n");
-		text[count++] = strdup("#define VARYING varying\n");
-	}
-	else if (version < 3.3f)
+	S32 major_version = gGLManager.mGLSLVersionMajor;
+	S32 minor_version = gGLManager.mGLSLVersionMinor;
+	
+	if (major_version == 1 && minor_version < 30)
 	{
-		//set version to 1.20
-		text[count++] = strdup("#version 120\n");
-		text[count++] = strdup("#define FXAA_GLSL_120 1\n");
-		text[count++] = strdup("#define FXAA_FAST_PIXEL_OFFSET 0\n");
-		text[count++] = strdup("#define ATTRIBUTE attribute\n");
-		text[count++] = strdup("#define VARYING varying\n");
+		if (minor_version < 10)
+		{
+			//should NEVER get here -- if major version is 1 and minor version is less than 10, 
+			// viewer should never attempt to use shaders, continuing will result in undefined behavior
+			llerrs << "Unsupported GLSL Version." << llendl;
+		}
+
+		if (minor_version <= 19)
+		{
+			text[count++] = strdup("#version 110\n");
+			text[count++] = strdup("#define ATTRIBUTE attribute\n");
+			text[count++] = strdup("#define VARYING varying\n");
+			text[count++] = strdup("#define VARYING_FLAT varying\n");
+		}
+		else if (minor_version <= 29)
+		{
+			//set version to 1.20
+			text[count++] = strdup("#version 120\n");
+			text[count++] = strdup("#define FXAA_GLSL_120 1\n");
+			text[count++] = strdup("#define FXAA_FAST_PIXEL_OFFSET 0\n");
+			text[count++] = strdup("#define ATTRIBUTE attribute\n");
+			text[count++] = strdup("#define VARYING varying\n");
+			text[count++] = strdup("#define VARYING_FLAT varying\n");
+		}
 	}
 	else
 	{  
-		if (version < 4.f)
+		if (major_version < 4)
 		{
 			//set version to 1.30
 			text[count++] = strdup("#version 130\n");
@@ -618,13 +626,17 @@ GLhandleARB LLShaderMgr::loadShaderFile(const std::string& filename, S32 & shade
 		{ //"varying" state is "out" in a vertex program, "in" in a fragment program 
 			// ("varying" is deprecated after version 1.20)
 			text[count++] = strdup("#define VARYING out\n");
+			text[count++] = strdup("#define VARYING_FLAT flat out\n");
 		}
 		else
 		{
 			text[count++] = strdup("#define VARYING in\n");
+			text[count++] = strdup("#define VARYING_FLAT flat in\n");
 		}
 
 		//backwards compatibility with legacy texture lookup syntax
+		text[count++] = strdup("#define texture2D texture\n");
+		text[count++] = strdup("#define texture2DRect texture\n");
 		text[count++] = strdup("#define textureCube texture\n");
 		text[count++] = strdup("#define texture2DLod textureLod\n");
 		text[count++] = strdup("#define	shadow2D(a,b) vec2(texture(a,b))\n");
@@ -651,11 +663,11 @@ GLhandleARB LLShaderMgr::loadShaderFile(const std::string& filename, S32 & shade
 		.
 		uniform sampler2D texN;
 		
-		VARYING float vary_texture_index;
+		VARYING uvec4 vary_texture_index;
 
 		vec4 diffuseLookup(vec2 texcoord)
 		{
-			switch (int(vary_texture_index+0.25))
+			switch (vary_texture_index.r))
 			{
 				case 0: return texture2D(tex0, texcoord);
 				case 1: return texture2D(tex1, texcoord);
@@ -679,7 +691,7 @@ GLhandleARB LLShaderMgr::loadShaderFile(const std::string& filename, S32 & shade
 
 		if (texture_index_channels > 1)
 		{
-			text[count++] = strdup("VARYING float vary_texture_index;\n");
+			text[count++] = strdup("VARYING_FLAT uvec4 vary_texture_index;\n");
 		}
 
 		text[count++] = strdup("vec4 diffuseLookup(vec2 texcoord)\n");
@@ -691,9 +703,9 @@ GLhandleARB LLShaderMgr::loadShaderFile(const std::string& filename, S32 & shade
 			text[count++] = strdup("return texture2D(tex0, texcoord);\n");
 			text[count++] = strdup("}\n");
 		}
-		else if (gGLManager.mGLVersion >= 3.f)
-		{ 
-			text[count++] = strdup("\tswitch (int(vary_texture_index+0.25))\n");
+		else if (major_version > 1 || minor_version >= 30)
+		{  //switches are supported in GLSL 1.30 and later
+			text[count++] = strdup("\tswitch (vary_texture_index.r)\n");
 			text[count++] = strdup("\t{\n");
 		
 			//switch body
@@ -708,28 +720,10 @@ GLhandleARB LLShaderMgr::loadShaderFile(const std::string& filename, S32 & shade
 			text[count++] = strdup("}\n");
 		}
 		else
-		{
-			//switches aren't supported, make block that looks like:
-			/*
-				int ti = int(vary_texture_index+0.25);
-				if (ti == 0) return texture2D(tex0, texcoord);
-				if (ti == 1) return texture2D(tex1, texcoord);
-				.
-				.
-				.
-				if (ti == N) return texture2D(texN, texcoord);
-			*/
-				
-			text[count++] = strdup("int ti = int(vary_texture_index+0.25);\n");
-			for (S32 i = 0; i < texture_index_channels; ++i)
-			{
-				std::string if_str = llformat("if (ti == %d) return texture2D(tex%d, texcoord);\n", i, i);
-				text[count++] = strdup(if_str.c_str());
-			}
-
-			text[count++] = strdup("\treturn vec4(1,0,1,1);\n");
-			text[count++] = strdup("}\n");
-		}			
+		{ //should never get here.  Indexed texture rendering requires GLSL 1.30 or later 
+			// (for passing integers between vertex and fragment shaders)
+			llerrs << "Indexed texture rendering requires GLSL 1.30 or later." << llendl;
+		}
 	}
 
 	//copy file into memory
diff --git a/indra/llrender/llvertexbuffer.cpp b/indra/llrender/llvertexbuffer.cpp
index e4a5cd0299..b2438ef824 100644
--- a/indra/llrender/llvertexbuffer.cpp
+++ b/indra/llrender/llvertexbuffer.cpp
@@ -284,6 +284,12 @@ void LLVertexBuffer::setupClientArrays(U32 data_mask)
 	{
 		bool error = false;
 
+		if (gGLManager.mGLSLVersionMajor < 2 && gGLManager.mGLSLVersionMinor < 30)
+		{
+			//make sure texture index is disabled
+			data_mask = data_mask & ~MAP_TEXTURE_INDEX;
+		}
+
 		if (LLGLSLShader::sNoFixedFunction)
 		{
 			for (U32 i = 0; i < TYPE_MAX; ++i)
@@ -1193,7 +1199,7 @@ void LLVertexBuffer::setupVertexArray()
 		1, //TYPE_WEIGHT,
 		4, //TYPE_WEIGHT4,
 		4, //TYPE_CLOTHWEIGHT,
-		1, //TYPE_TEXTURE_INDEX
+		4, //TYPE_TEXTURE_INDEX
 	};
 
 	U32 attrib_type[] =
@@ -1210,7 +1216,24 @@ void LLVertexBuffer::setupVertexArray()
 		GL_FLOAT, //TYPE_WEIGHT,
 		GL_FLOAT, //TYPE_WEIGHT4,
 		GL_FLOAT, //TYPE_CLOTHWEIGHT,
-		GL_FLOAT, //TYPE_TEXTURE_INDEX
+		GL_UNSIGNED_BYTE, //TYPE_TEXTURE_INDEX
+	};
+
+	bool attrib_integer[] = 
+	{
+		false, //TYPE_VERTEX,
+		false, //TYPE_NORMAL,
+		false, //TYPE_TEXCOORD0,
+		false, //TYPE_TEXCOORD1,
+		false, //TYPE_TEXCOORD2,
+		false, //TYPE_TEXCOORD3,
+		false, //TYPE_COLOR,
+		false, //TYPE_EMISSIVE,
+		false, //TYPE_BINORMAL,
+		false, //TYPE_WEIGHT,
+		false, //TYPE_WEIGHT4,
+		false, //TYPE_CLOTHWEIGHT,
+		true, //TYPE_TEXTURE_INDEX
 	};
 
 	U32 attrib_normalized[] =
@@ -1238,7 +1261,19 @@ void LLVertexBuffer::setupVertexArray()
 		if (mTypeMask & (1 << i))
 		{
 			glEnableVertexAttribArrayARB(i);
-			glVertexAttribPointerARB(i, attrib_size[i], attrib_type[i], attrib_normalized[i], sTypeSize[i], (void*) mOffsets[i]); 
+
+			if (attrib_integer)
+			{
+				//glVertexattribIPointer requires GLSL 1.30 or later
+				if (gGLManager.mGLSLVersionMajor > 1 || gGLManager.mGLSLVersionMinor >= 30)
+				{
+					glVertexAttribIPointer(i, attrib_size[i], attrib_type[i], sTypeSize[i], (void*) mOffsets[i]); 
+				}
+			}
+			else
+			{
+				glVertexAttribPointerARB(i, attrib_size[i], attrib_type[i], attrib_normalized[i], sTypeSize[i], (void*) mOffsets[i]); 
+			}
 		}
 		else
 		{
@@ -2220,11 +2255,12 @@ void LLVertexBuffer::setupVertexBuffer(U32 data_mask)
 			void* ptr = (void*)(base + mOffsets[TYPE_CLOTHWEIGHT]);
 			glVertexAttribPointerARB(loc, 4, GL_FLOAT, GL_TRUE,  LLVertexBuffer::sTypeSize[TYPE_CLOTHWEIGHT], ptr);
 		}
-		if (data_mask & MAP_TEXTURE_INDEX)
+		if (data_mask & MAP_TEXTURE_INDEX && 
+				(gGLManager.mGLSLVersionMajor >= 2 || gGLManager.mGLSLVersionMinor >= 30)) //indexed texture rendering requires GLSL 1.30 or later
 		{
 			S32 loc = TYPE_TEXTURE_INDEX;
 			void *ptr = (void*) (base + mOffsets[TYPE_VERTEX] + 12);
-			glVertexAttribPointerARB(loc, 1, GL_FLOAT, GL_FALSE, LLVertexBuffer::sTypeSize[TYPE_VERTEX], ptr);
+			glVertexAttribIPointer(loc, 4, GL_UNSIGNED_BYTE, LLVertexBuffer::sTypeSize[TYPE_VERTEX], ptr);
 		}
 		if (data_mask & MAP_VERTEX)
 		{