OpenGL2: Fix WebGL and add fallback to GLES2

README.md

@@ -168,11 +168,12 @@ embedded System-on-a-Chip and mobile platforms.
 
 The opengl1 renderer does not have OpenGL ES support.
 
-The `r_useOpenGLES` cvar controls whether to use OpenGL or OpenGL ES API.
-Set to -1 for auto (default), 0 for OpenGL, and 1 for OpenGL ES. It should be
+The opengl2 renderer will try both OpenGL and OpenGL ES APIs to find one that
+works. The `r_preferOpenGLES` cvar controls which API to try first.
+Set it to -1 for auto (default), 0 for OpenGL, and 1 for OpenGL ES. It should be
 set using command line arguments:
 
-    ioquake3 +set cl_renderer opengl2 +set r_useOpenGLES 1
+    ioquake3 +set cl_renderer opengl2 +set r_preferOpenGLES 1
 
 
 # Console

code/renderercommon/qgl.h

@@ -80,7 +80,6 @@ extern void (APIENTRYP qglUnlockArraysEXT) (void);
 	GLE(void, TexParameterf, GLenum target, GLenum pname, GLfloat param) \
 	GLE(void, TexParameteri, GLenum target, GLenum pname, GLint param) \
 	GLE(void, TexSubImage2D, GLenum target, GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLenum type, const GLvoid *pixels) \
-	GLE(void, Translatef, GLfloat x, GLfloat y, GLfloat z) \
 	GLE(void, Viewport, GLint x, GLint y, GLsizei width, GLsizei height) \
 
 // OpenGL 1.0/1.1 and OpenGL ES 1.x but not OpenGL 3.2 core profile
@@ -98,6 +97,7 @@ extern void (APIENTRYP qglUnlockArraysEXT) (void);
 	GLE(void, ShadeModel, GLenum mode) \
 	GLE(void, TexCoordPointer, GLint size, GLenum type, GLsizei stride, const GLvoid *ptr) \
 	GLE(void, TexEnvf, GLenum target, GLenum pname, GLfloat param) \
+	GLE(void, Translatef, GLfloat x, GLfloat y, GLfloat z) \
 	GLE(void, VertexPointer, GLint size, GLenum type, GLsizei stride, const GLvoid *ptr) \
 
 // OpenGL 1.0/1.1 and 3.2 core profile but not OpenGL ES 1.x

code/renderergl2/glsl/depthblur_fp.glsl

@@ -52,10 +52,9 @@ vec4 depthGaussian1D(sampler2D imageMap, sampler2D depthMap, vec2 tex, float zFa
 #endif
 
 	float zLimit = 5.0 / zFar;
-	int i, j;
-	for (i = 0; i < 2; i++)
+	for (int i = 0; i < 2; i++)
 	{
-		for (j = 1; j < BLUR_SIZE; j++)
+		for (int j = 1; j < BLUR_SIZE; j++)
 		{
 			vec2 offset = direction * (float(j) - 0.25) + nudge;
 #if defined(USE_DEPTH)

code/renderergl2/glsl/ssao_fp.glsl

@@ -77,8 +77,7 @@ float ambientOcclusion(sampler2D depthMap, const vec2 tex, const float zFarDivZN
 
 	float invZFar = 1.0 / zFar;
 	float zLimit = 20.0 * invZFar;
-	int i;
-	for (i = 0; i < NUM_SAMPLES; i++)
+	for (int i = 0; i < NUM_SAMPLES; i++)
 	{
 		vec2 offset = rmat * poissonDisc[i] * offsetScale;
 		float sampleDiff = getLinearDepth(depthMap, tex + offset, zFarDivZNear) - sampleZ;

code/renderergl2/tr_extensions.c

@@ -73,12 +73,23 @@ void GLimp_InitExtraExtensions(void)
 			goto done;
 
 		extension = "GL_EXT_occlusion_query_boolean";
-		if (SDL_GL_ExtensionSupported(extension))
+		if (qglesMajorVersion >= 3 || SDL_GL_ExtensionSupported(extension))
 		{
 			glRefConfig.occlusionQuery = qtrue;
 			glRefConfig.occlusionQueryTarget = GL_ANY_SAMPLES_PASSED;
 
-			QGL_ARB_occlusion_query_PROCS;
+			if (qglesMajorVersion >= 3) {
+				QGL_ARB_occlusion_query_PROCS;
+			} else {
+				// GL_EXT_occlusion_query_boolean uses EXT suffix
+#undef GLE
+#define GLE(ret, name, ...) qgl##name = (name##proc *) SDL_GL_GetProcAddress("gl" #name "EXT");
+
+				QGL_ARB_occlusion_query_PROCS;
+
+#undef GLE
+#define GLE(ret, name, ...) qgl##name = (name##proc *) SDL_GL_GetProcAddress("gl" #name);
+			}
 
 			ri.Printf(PRINT_ALL, result[glRefConfig.occlusionQuery], extension);
 		}
@@ -137,7 +148,7 @@ void GLimp_InitExtraExtensions(void)
 
 		// GL_OES_element_index_uint
 		extension = "GL_OES_element_index_uint";
-		if (SDL_GL_ExtensionSupported(extension))
+		if (qglesMajorVersion >= 3 || SDL_GL_ExtensionSupported(extension))
 		{
 			glRefConfig.vaoCacheGlIndexType = GL_UNSIGNED_INT;
 			glRefConfig.vaoCacheGlIndexSize = sizeof(unsigned int);

code/renderergl2/tr_init.c

@@ -283,7 +283,12 @@ static void InitOpenGL( void )
 		glRefConfig.maxVertexAttribs = temp;
 
 		// reserve 160 components for other uniforms
-		qglGetIntegerv( GL_MAX_VERTEX_UNIFORM_COMPONENTS, &temp );
+		if ( qglesMajorVersion ) {
+			qglGetIntegerv( GL_MAX_VERTEX_UNIFORM_VECTORS, &temp );
+			temp *= 4;
+		} else {
+			qglGetIntegerv( GL_MAX_VERTEX_UNIFORM_COMPONENTS, &temp );
+		}
 		glRefConfig.glslMaxAnimatedBones = Com_Clamp( 0, IQM_MAX_JOINTS, ( temp - 160 ) / 16 );
 		if ( glRefConfig.glslMaxAnimatedBones < 12 ) {
 			glRefConfig.glslMaxAnimatedBones = 0;

code/sdl/sdl_glimp.c

@@ -52,7 +52,7 @@ cvar_t *r_allowSoftwareGL; // Don't abort out if a hardware visual can't be obta
 cvar_t *r_allowResize; // make window resizable
 cvar_t *r_centerWindow;
 cvar_t *r_sdlDriver;
-cvar_t *r_useOpenGLES;
+cvar_t *r_preferOpenGLES;
 
 int qglMajorVersion, qglMinorVersion;
 int qglesMajorVersion, qglesMinorVersion;
@@ -394,6 +394,12 @@ GLimp_SetMode
 */
 static int GLimp_SetMode(int mode, qboolean fullscreen, qboolean noborder, qboolean fixedFunction)
 {
+	struct GLimp_ContextType {
+		int profileMask;
+		int majorVersion;
+		int minorVersion;
+	} contexts[3];
+	int numContexts, type;
 	const char *glstring;
 	int perChannelColorBits;
 	int colorBits, depthBits, stencilBits;
@@ -524,6 +530,48 @@ static int GLimp_SetMode(int mode, qboolean fullscreen, qboolean noborder, qbool
 	stencilBits = r_stencilbits->value;
 	samples = r_ext_multisample->value;
 
+	numContexts = 0;
+
+	if ( !fixedFunction ) {
+		int profileMask;
+		qboolean preferOpenGLES;
+
+		SDL_GL_ResetAttributes();
+		SDL_GL_GetAttribute( SDL_GL_CONTEXT_PROFILE_MASK, &profileMask );
+
+		preferOpenGLES = ( r_preferOpenGLES->integer == 1 ||
+		                 ( r_preferOpenGLES->integer == -1 && profileMask == SDL_GL_CONTEXT_PROFILE_ES ) );
+
+		if ( preferOpenGLES ) {
+			contexts[numContexts].profileMask = SDL_GL_CONTEXT_PROFILE_ES;
+			contexts[numContexts].majorVersion = 2;
+			contexts[numContexts].minorVersion = 0;
+			numContexts++;
+		}
+
+		contexts[numContexts].profileMask = SDL_GL_CONTEXT_PROFILE_CORE;
+		contexts[numContexts].majorVersion = 3;
+		contexts[numContexts].minorVersion = 2;
+		numContexts++;
+
+		contexts[numContexts].profileMask = 0;
+		contexts[numContexts].majorVersion = 2;
+		contexts[numContexts].minorVersion = 0;
+		numContexts++;
+
+		if ( !preferOpenGLES ) {
+			contexts[numContexts].profileMask = SDL_GL_CONTEXT_PROFILE_ES;
+			contexts[numContexts].majorVersion = 2;
+			contexts[numContexts].minorVersion = 0;
+			numContexts++;
+		}
+	} else {
+		contexts[numContexts].profileMask = 0;
+		contexts[numContexts].majorVersion = 1;
+		contexts[numContexts].minorVersion = 1;
+		numContexts++;
+	}
+
 	for (i = 0; i < 16; i++)
 	{
 		int testColorBits, testDepthBits, testStencilBits;
@@ -656,116 +704,68 @@ static int GLimp_SetMode(int mode, qboolean fullscreen, qboolean noborder, qbool
 
 		SDL_SetWindowIcon( SDL_window, icon );
 
-		if (!fixedFunction)
-		{
-			int profileMask;
-
-			SDL_GL_GetAttribute( SDL_GL_CONTEXT_PROFILE_MASK, &profileMask );
-
-			if ( r_useOpenGLES->integer == 1 || ( r_useOpenGLES->integer == -1 && profileMask == SDL_GL_CONTEXT_PROFILE_ES ) )
-			{
-				ri.Printf( PRINT_ALL, "Trying to get an OpenGL ES 2.0 context\n" );
-				SDL_GL_SetAttribute( SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES );
-				SDL_GL_SetAttribute( SDL_GL_CONTEXT_MAJOR_VERSION, 2 );
-				SDL_GL_SetAttribute( SDL_GL_CONTEXT_MINOR_VERSION, 0 );
+		for ( type = 0; type < numContexts; type++ ) {
+			char contextName[32];
 
-				SDL_glContext = SDL_GL_CreateContext( SDL_window );
-				if ( !SDL_glContext )
-				{
-					ri.Printf( PRINT_ALL, "SDL_GL_CreateContext failed: %s\n", SDL_GetError() );
-				}
-				else
-				{
-					ri.Printf( PRINT_ALL, "SDL_GL_CreateContext succeeded.\n" );
-
-					if ( !GLimp_GetProcAddresses( fixedFunction ) )
-					{
-						ri.Printf( PRINT_ALL, "GLimp_GetProcAddresses() failed for OpenGL ES 2.0 context\n" );
-						GLimp_ClearProcAddresses();
-						SDL_GL_DeleteContext( SDL_glContext );
-						SDL_glContext = NULL;
-					}
-				}
+			switch ( contexts[type].profileMask ) {
+				default:
+				case 0:
+					Com_sprintf( contextName, sizeof( contextName ), "OpenGL %d.%d",
+					             contexts[type].majorVersion, contexts[type].minorVersion );
+					break;
+				case SDL_GL_CONTEXT_PROFILE_CORE:
+					Com_sprintf( contextName, sizeof( contextName ), "OpenGL %d.%d Core",
+					             contexts[type].majorVersion, contexts[type].minorVersion );
+					break;
+				case SDL_GL_CONTEXT_PROFILE_ES:
+					Com_sprintf( contextName, sizeof( contextName ), "OpenGL ES %d.%d",
+					             contexts[type].majorVersion, contexts[type].minorVersion );
+					break;
 			}
 
-			if ( !SDL_glContext )
-			{
-				ri.Printf( PRINT_ALL, "Trying to get an OpenGL 3.2 core context\n" );
-				SDL_GL_SetAttribute( SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE );
-				SDL_GL_SetAttribute( SDL_GL_CONTEXT_MAJOR_VERSION, 3 );
-				SDL_GL_SetAttribute( SDL_GL_CONTEXT_MINOR_VERSION, 2 );
-
-				SDL_glContext = SDL_GL_CreateContext( SDL_window );
-				if ( !SDL_glContext )
-				{
-					ri.Printf( PRINT_ALL, "SDL_GL_CreateContext failed: %s\n", SDL_GetError() );
-				}
-				else
-				{
-					const char *renderer;
-
-					ri.Printf( PRINT_ALL, "SDL_GL_CreateContext succeeded.\n" );
-
-					if ( GLimp_GetProcAddresses( fixedFunction ) )
-					{
-						renderer = (const char *)qglGetString( GL_RENDERER );
-					}
-					else
-					{
-						ri.Printf( PRINT_ALL, "GLimp_GetProcAddresses() failed for OpenGL 3.2 core context\n" );
-						renderer = NULL;
-					}
-
-					if ( !renderer || strstr( renderer, "Software Renderer" ) || strstr( renderer, "Software Rasterizer" ) )
-					{
-						if ( renderer )
-							ri.Printf(PRINT_ALL, "GL_RENDERER is %s, rejecting context\n", renderer);
-
-						GLimp_ClearProcAddresses();
-						SDL_GL_DeleteContext( SDL_glContext );
-						SDL_glContext = NULL;
-					}
-				}
-			}
+			SDL_GL_SetAttribute( SDL_GL_CONTEXT_PROFILE_MASK, contexts[type].profileMask );
+			SDL_GL_SetAttribute( SDL_GL_CONTEXT_MAJOR_VERSION, contexts[type].majorVersion );
+			SDL_GL_SetAttribute( SDL_GL_CONTEXT_MINOR_VERSION, contexts[type].minorVersion );
 
+			SDL_glContext = SDL_GL_CreateContext( SDL_window );
 			if ( !SDL_glContext )
 			{
-				ri.Printf( PRINT_ALL, "Trying to get an OpenGL 2.0 context\n" );
-
-				SDL_GL_SetAttribute( SDL_GL_CONTEXT_PROFILE_MASK, 0 );
-				SDL_GL_SetAttribute( SDL_GL_CONTEXT_MAJOR_VERSION, 2 );
-				SDL_GL_SetAttribute( SDL_GL_CONTEXT_MINOR_VERSION, 0 );
-			}
-		}
-		else
-		{
-			SDL_GL_SetAttribute( SDL_GL_CONTEXT_PROFILE_MASK, 0 );
-			SDL_GL_SetAttribute( SDL_GL_CONTEXT_MAJOR_VERSION, 1 );
-			SDL_GL_SetAttribute( SDL_GL_CONTEXT_MINOR_VERSION, 1 );
-
-			SDL_glContext = NULL;
-		}
-
-		if ( !SDL_glContext )
-		{
-			if( ( SDL_glContext = SDL_GL_CreateContext( SDL_window ) ) == NULL )
-			{
-				ri.Printf( PRINT_DEVELOPER, "SDL_GL_CreateContext failed: %s\n", SDL_GetError( ) );
-				SDL_DestroyWindow( SDL_window );
-				SDL_window = NULL;
+				ri.Printf( PRINT_ALL, "SDL_GL_CreateContext() for %s context failed: %s\n", contextName, SDL_GetError() );
 				continue;
 			}
 
 			if ( !GLimp_GetProcAddresses( fixedFunction ) )
 			{
-				ri.Printf( PRINT_ALL, "GLimp_GetProcAddresses() failed\n" );
+				ri.Printf( PRINT_ALL, "GLimp_GetProcAddresses() for %s context failed\n", contextName );
 				GLimp_ClearProcAddresses();
 				SDL_GL_DeleteContext( SDL_glContext );
 				SDL_glContext = NULL;
-				SDL_DestroyWindow( SDL_window );
-				SDL_window = NULL;
 				continue;
 			}
+
+			if ( contexts[type].profileMask == SDL_GL_CONTEXT_PROFILE_CORE ) {
+				const char *renderer;
+
+				renderer = (const char *)qglGetString( GL_RENDERER );
+
+				if ( !renderer || strstr( renderer, "Software Renderer" ) || strstr( renderer, "Software Rasterizer" ) )
+				{
+					ri.Printf( PRINT_ALL, "GL_RENDERER is %s, rejecting %s context\n", renderer, contextName );
+
+					GLimp_ClearProcAddresses();
+					SDL_GL_DeleteContext( SDL_glContext );
+					SDL_glContext = NULL;
+					continue;
+				}
+			}
+
+			break;
+		}
+
+		if ( !SDL_glContext ) {
+			SDL_DestroyWindow( SDL_window );
+			SDL_window = NULL;
+			continue;
 		}
 
 		qglClearColor( 0, 0, 0, 1 );
@@ -1055,7 +1055,7 @@ void GLimp_Init( qboolean fixedFunction )
 	r_sdlDriver = ri.Cvar_Get( "r_sdlDriver", "", CVAR_ROM );
 	r_allowResize = ri.Cvar_Get( "r_allowResize", "0", CVAR_ARCHIVE | CVAR_LATCH );
 	r_centerWindow = ri.Cvar_Get( "r_centerWindow", "0", CVAR_ARCHIVE | CVAR_LATCH );
-	r_useOpenGLES = ri.Cvar_Get( "r_useOpenGLES", "-1", CVAR_ARCHIVE | CVAR_LATCH );
+	r_preferOpenGLES = ri.Cvar_Get( "r_preferOpenGLES", "-1", CVAR_ARCHIVE | CVAR_LATCH );
 
 	if( ri.Cvar_VariableIntegerValue( "com_abnormalExit" ) )
 	{

opengl2-readme.md

@@ -65,10 +65,10 @@ For Win32:
 
 Cvars for API:
 
-* `r_useOpenGLES`                   - This enables using OpenGL ES 2+.
-                                   Many features are not supported such as sun shadows and HDR.
-                                     1 - Use OpenGL ES.
-                                     0 - Use desktop OpenGL.
+* `r_preferOpenGLES`                - This sets the preference for using OpenGL or OpenGL ES 2.
+                                   Many features are not supported when using OpenGL ES such as sun shadows and HDR.
+                                     1 - Prefer OpenGL ES 2+.
+                                     0 - Prefer desktop OpenGL.
                                      -1 - Automatically pick (default).
 
 Cvars for simple rendering features: