OPENGL: Merge both OpenGL contexts

backends/graphics/android/android-graphics.cpp

@@ -93,19 +93,22 @@ void AndroidGraphicsManager::initSurface() {
 	assert(!JNI::haveSurface());
 	JNI::initSurface();
 
-	// Notify the OpenGL code about our context.
-	setContextType(OpenGL::kContextGLES2);
-
 	if (JNI::egl_bits_per_pixel == 16) {
 		// We default to RGB565 and RGBA5551 which is closest to what we setup in Java side
-		notifyContextCreate(Graphics::PixelFormat(2, 5, 6, 5, 0, 11, 5, 0, 0), Graphics::PixelFormat(2, 5, 5, 5, 1, 11, 6, 1, 0));
+		notifyContextCreate(OpenGL::kContextGLES2,
+				Graphics::PixelFormat(2, 5, 6, 5, 0, 11, 5, 0, 0),
+				Graphics::PixelFormat(2, 5, 5, 5, 1, 11, 6, 1, 0));
 	} else {
 		// If not 16, this must be 24 or 32 bpp so make use of them
+		notifyContextCreate(OpenGL::kContextGLES2,
 #ifdef SCUMM_BIG_ENDIAN
-		notifyContextCreate(Graphics::PixelFormat(3, 8, 8, 8, 0, 16, 8, 0, 0), Graphics::PixelFormat(4, 8, 8, 8, 8, 24, 16, 8, 0));
+				Graphics::PixelFormat(3, 8, 8, 8, 0, 16, 8, 0, 0),
+				Graphics::PixelFormat(4, 8, 8, 8, 8, 24, 16, 8, 0)
 #else
-		notifyContextCreate(Graphics::PixelFormat(3, 8, 8, 8, 0, 0, 8, 16, 0), Graphics::PixelFormat(4, 8, 8, 8, 8, 0, 8, 16, 24));
+				Graphics::PixelFormat(3, 8, 8, 8, 0, 0, 8, 16, 0),
+				Graphics::PixelFormat(4, 8, 8, 8, 8, 0, 8, 16, 24)
 #endif
+		);
 	}
 
 	if (_touchcontrols) {
@@ -203,8 +206,8 @@ void AndroidGraphicsManager::refreshScreen() {
 
 void AndroidGraphicsManager::touchControlDraw(int16 x, int16 y, int16 w, int16 h, const Common::Rect &clip) {
 	_backBuffer.enableBlend(OpenGL::Framebuffer::kBlendModeTraditionalTransparency);
-	OpenGL::g_context.getActivePipeline()->drawTexture(_touchcontrols->getGLTexture(),
+	OpenGL::Pipeline::getActivePipeline()->drawTexture(_touchcontrols->getGLTexture(),
-		                                           x, y, w, h, clip);
+	                                                   x, y, w, h, clip);
 }
 
 void AndroidGraphicsManager::touchControlNotifyChanged() {
@@ -212,12 +215,6 @@ void AndroidGraphicsManager::touchControlNotifyChanged() {
 	_forceRedraw = true;
 }
 
-void *AndroidGraphicsManager::getProcAddress(const char *name) const {
-	ENTER("%s", name);
-
-	return androidGLgetProcAddress(name);
-}
-
 bool AndroidGraphicsManager::notifyMousePosition(Common::Point &mouse) {
 	mouse.x = CLIP<int16>(mouse.x, _activeArea.drawRect.left, _activeArea.drawRect.right);
 	mouse.y = CLIP<int16>(mouse.y, _activeArea.drawRect.top, _activeArea.drawRect.bottom);

backends/graphics/android/android-graphics.h

@@ -98,8 +98,6 @@ protected:
 
 	void refreshScreen() override;
 
-	void *getProcAddress(const char *name) const override;
-
 private:
 	OpenGL::Surface *_touchcontrols;
 	int _old_touch_mode;

backends/graphics/opengl/context.cpp

@@ -1,240 +0,0 @@
-/* ScummVM - Graphic Adventure Engine
- *
- * ScummVM is the legal property of its developers, whose names
- * are too numerous to list here. Please refer to the COPYRIGHT
- * file distributed with this source distribution.
- *
- * 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, either version 3 of the License, or
- * (at your option) any later version.
- *
- * 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 for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- *
- */
-
-#define GLAD_GL_IMPLEMENTATION
-
-#include "backends/graphics/opengl/opengl-sys.h"
-#include "backends/graphics/opengl/opengl-graphics.h"
-#include "backends/graphics/opengl/shader.h"
-#include "backends/graphics/opengl/pipelines/pipeline.h"
-#include "backends/graphics/opengl/framebuffer.h"
-
-#include "common/tokenizer.h"
-#include "common/debug.h"
-
-namespace OpenGL {
-
-void Context::reset() {
-	maxTextureSize = 0;
-
-	majorVersion = 0;
-	minorVersion = 0;
-
-	NPOTSupported = false;
-	shadersSupported = false;
-	multitextureSupported = false;
-	framebufferObjectSupported = false;
-	packedPixelsSupported = false;
-	textureEdgeClampSupported = false;
-
-	isInitialized = false;
-
-	activePipeline = nullptr;
-}
-
-Pipeline *Context::setPipeline(Pipeline *pipeline) {
-	Pipeline *oldPipeline = activePipeline;
-	if (oldPipeline) {
-		oldPipeline->deactivate();
-	}
-
-	activePipeline = pipeline;
-	if (activePipeline) {
-		activePipeline->activate();
-	}
-
-	return oldPipeline;
-}
-
-Context g_context;
-
-void OpenGLGraphicsManager::setContextType(ContextType type) {
-#if USE_FORCED_GL
-	type = kContextGL;
-#elif USE_FORCED_GLES
-	type = kContextGLES;
-#elif USE_FORCED_GLES2
-	type = kContextGLES2;
-#endif
-
-	g_context.type = type;
-}
-
-#ifdef USE_GLAD
-static GLADapiproc loadFunc(void *userptr, const char *name) {
-	OpenGLGraphicsManager *openglGraphicsManager = (OpenGLGraphicsManager *)userptr;
-	return (GLADapiproc)openglGraphicsManager->getProcAddress(name);
-}
-#endif
-
-void OpenGLGraphicsManager::initializeGLContext() {
-	// Initialize default state.
-	g_context.reset();
-
-#ifdef USE_GLAD
-	switch (g_context.type) {
-	case kContextGL:
-		gladLoadGLUserPtr(loadFunc, this);
-		break;
-
-	case kContextGLES:
-		gladLoadGLES1UserPtr(loadFunc, this);
-		break;
-
-	case kContextGLES2:
-		gladLoadGLES2UserPtr(loadFunc, this);
-		break;
-
-	default:
-		break;
-	}
-#endif
-
-	g_context.isInitialized = true;
-
-	// Obtain maximum texture size.
-	GL_CALL(glGetIntegerv(GL_MAX_TEXTURE_SIZE, &g_context.maxTextureSize));
-	debug(5, "OpenGL maximum texture size: %d", g_context.maxTextureSize);
-
-	const char *verString = (const char *)glGetString(GL_VERSION);
-	debug(5, "OpenGL version: %s", verString);
-
-	if (g_context.type == kContextGL) {
-		// OpenGL version number is either of the form major.minor or major.minor.release,
-		// where the numbers all have one or more digits
-		if (sscanf(verString, "%d.%d", &g_context.majorVersion, &g_context.minorVersion) != 2) {
-			g_context.majorVersion = g_context.minorVersion = 0;
-			warning("Could not parse GL version '%s'", verString);
-		}
-	} else if (g_context.type == kContextGLES) {
-		// The form of the string is "OpenGL ES-<profile> <major>.<minor>",
-		// where <profile> is either "CM" (Common) or "CL" (Common-Lite),
-		// and <major> and <minor> are integers.
-		char profile[3];
-		if (sscanf(verString, "OpenGL ES-%2s %d.%d", profile,
-					&g_context.majorVersion, &g_context.minorVersion) != 3) {
-			g_context.majorVersion = g_context.minorVersion = 0;
-			warning("Could not parse GL ES version '%s'", verString);
-		}
-	} else if (g_context.type == kContextGLES2) {
-		// The version is of the form
-		// OpenGL<space>ES<space><version number><space><vendor-specific information>
-		// version number format is not defined
-		// There is only OpenGL ES 2.0 anyway
-		if (sscanf(verString, "OpenGL ES %d.%d", &g_context.majorVersion, &g_context.minorVersion) != 2) {
-			g_context.minorVersion = 0;
-			if (sscanf(verString, "OpenGL ES %d ", &g_context.majorVersion) != 1) {
-				g_context.majorVersion = 0;
-				warning("Could not parse GL ES 2 version '%s'", verString);
-			}
-		}
-	}
-
-	const char *extString = (const char *)glGetString(GL_EXTENSIONS);
-	debug(5, "OpenGL extensions: %s", extString);
-
-	bool ARBShaderObjects = false;
-	bool ARBShadingLanguage100 = false;
-	bool ARBVertexShader = false;
-	bool ARBFragmentShader = false;
-
-	Common::StringTokenizer tokenizer(extString, " ");
-	while (!tokenizer.empty()) {
-		Common::String token = tokenizer.nextToken();
-
-		if (token == "GL_ARB_texture_non_power_of_two" || token == "GL_OES_texture_npot") {
-			g_context.NPOTSupported = true;
-		} else if (token == "GL_ARB_shader_objects") {
-			ARBShaderObjects = true;
-		} else if (token == "GL_ARB_shading_language_100") {
-			ARBShadingLanguage100 = true;
-		} else if (token == "GL_ARB_vertex_shader") {
-			ARBVertexShader = true;
-		} else if (token == "GL_ARB_fragment_shader") {
-			ARBFragmentShader = true;
-		} else if (token == "GL_ARB_multitexture") {
-			g_context.multitextureSupported = true;
-		} else if (token == "GL_ARB_framebuffer_object") {
-			g_context.framebufferObjectSupported = true;
-		} else if (token == "GL_EXT_packed_pixels" || token == "GL_APPLE_packed_pixels") {
-			g_context.packedPixelsSupported = true;
-		} else if (token == "GL_SGIS_texture_edge_clamp") {
-			g_context.textureEdgeClampSupported = true;
-		}
-	}
-
-	if (g_context.type == kContextGLES2) {
-		// GLES2 always has (limited) NPOT support.
-		g_context.NPOTSupported = true;
-
-		// GLES2 always has shader support.
-		g_context.shadersSupported = true;
-
-		// GLES2 always has multi texture support.
-		g_context.multitextureSupported = true;
-
-		// GLES2 always has FBO support.
-		g_context.framebufferObjectSupported = true;
-	} else {
-		g_context.shadersSupported = ARBShaderObjects & ARBShadingLanguage100 & ARBVertexShader & ARBFragmentShader;
-	}
-
-	// OpenGL 1.2 and later always has packed pixels and texture edge clamp support
-	if (g_context.type != kContextGL || g_context.isGLVersionOrHigher(1, 2)) {
-		g_context.packedPixelsSupported = true;
-		g_context.textureEdgeClampSupported = true;
-	}
-
-	// Log context type.
-	switch (g_context.type) {
-	case kContextGL:
-		debug(5, "OpenGL: GL context initialized");
-		break;
-
-	case kContextGLES:
-		debug(5, "OpenGL: GLES context initialized");
-		break;
-
-	case kContextGLES2:
-		debug(5, "OpenGL: GLES2 context initialized");
-		break;
-
-	default:
-		warning("OpenGL: Unknown context initialized");
-		break;
-	}
-
-	// Log features supported by GL context.
-#if !USE_FORCED_GLES
-	if (g_context.shadersSupported)
-		debug(5, "GLSL version: %s", glGetString(GL_SHADING_LANGUAGE_VERSION));
-#endif
-	debug(5, "OpenGL vendor: %s", glGetString(GL_VENDOR));
-	debug(5, "OpenGL renderer: %s", glGetString(GL_RENDERER));
-	debug(5, "OpenGL: NPOT texture support: %d", g_context.NPOTSupported);
-	debug(5, "OpenGL: Shader support: %d", g_context.shadersSupported);
-	debug(5, "OpenGL: Multitexture support: %d", g_context.multitextureSupported);
-	debug(5, "OpenGL: FBO support: %d", g_context.framebufferObjectSupported);
-	debug(5, "OpenGL: Packed pixels support: %d", g_context.packedPixelsSupported);
-	debug(5, "OpenGL: Texture edge clamping support: %d", g_context.textureEdgeClampSupported);
-}
-
-} // End of namespace OpenGL

backends/graphics/opengl/debug.cpp

@@ -20,11 +20,12 @@
  */
 
 #include "backends/graphics/opengl/debug.h"
-#include "backends/graphics/opengl/opengl-sys.h"
 
 #include "common/str.h"
 #include "common/textconsole.h"
 
+#include "graphics/opengl/system_headers.h"
+
 #ifdef OPENGL_DEBUG
 
 namespace OpenGL {

backends/graphics/opengl/debug.h

@@ -22,6 +22,8 @@
 #ifndef BACKENDS_GRAPHICS_OPENGL_DEBUG_H
 #define BACKENDS_GRAPHICS_OPENGL_DEBUG_H
 
+#include "graphics/opengl/context.h"
+
 #define OPENGL_DEBUG
 
 #ifdef OPENGL_DEBUG
@@ -35,4 +37,13 @@ void checkGLError(const char *expr, const char *file, int line);
 #define GL_WRAP_DEBUG(call, name) do { (call); } while (false)
 #endif
 
+#define GL_CALL(x)                 GL_WRAP_DEBUG(x, x)
+#define GL_CALL_SAFE(func, params) \
+	do { \
+		if (OpenGLContext.type != kContextNone) { \
+			GL_CALL(func params); \
+		} \
+	} while (0)
+#define GL_ASSIGN(var, x)          GL_WRAP_DEBUG(var = x, x)
+
 #endif

backends/graphics/opengl/framebuffer.cpp

@@ -19,6 +19,7 @@
  *
  */
 
+#include "backends/graphics/opengl/debug.h"
 #include "backends/graphics/opengl/framebuffer.h"
 #include "backends/graphics/opengl/texture.h"
 #include "backends/graphics/opengl/pipelines/pipeline.h"
@@ -96,7 +97,7 @@ void Framebuffer::applyViewport() {
 }
 
 void Framebuffer::applyProjectionMatrix() {
-	g_context.getActivePipeline()->setProjectionMatrix(_projectionMatrix);
+	Pipeline::getActivePipeline()->setProjectionMatrix(_projectionMatrix);
 }
 
 void Framebuffer::applyClearColor() {
@@ -139,7 +140,7 @@ void Framebuffer::applyScissorBox() {
 
 void Backbuffer::activateInternal() {
 #if !USE_FORCED_GLES
-	if (g_context.framebufferObjectSupported) {
+	if (OpenGLContext.framebufferObjectSupported) {
 		GL_CALL(glBindFramebuffer(GL_FRAMEBUFFER, 0));
 	}
 #endif

backends/graphics/opengl/framebuffer.h

@@ -22,7 +22,7 @@
 #ifndef BACKENDS_GRAPHICS_OPENGL_FRAMEBUFFER_H
 #define BACKENDS_GRAPHICS_OPENGL_FRAMEBUFFER_H
 
-#include "backends/graphics/opengl/opengl-sys.h"
+#include "graphics/opengl/system_headers.h"
 
 namespace OpenGL {
 

backends/graphics/opengl/opengl-graphics.cpp

@@ -21,6 +21,7 @@
 
 
 #include "backends/graphics/opengl/opengl-graphics.h"
+#include "backends/graphics/opengl/debug.h"
 #include "backends/graphics/opengl/texture.h"
 #include "backends/graphics/opengl/pipelines/pipeline.h"
 #include "backends/graphics/opengl/pipelines/fixed.h"
@@ -79,7 +80,7 @@ OpenGLGraphicsManager::OpenGLGraphicsManager()
 #endif
 	{
 	memset(_gamePalette, 0, sizeof(_gamePalette));
-	g_context.reset();
+	OpenGLContext.reset();
 }
 
 OpenGLGraphicsManager::~OpenGLGraphicsManager() {
@@ -391,8 +392,8 @@ OSystem::TransactionError OpenGLGraphicsManager::endGFXTransaction() {
 		   // a context existing before, which means we don't know the maximum
 		   // supported texture size before this. Thus, we check whether the
 		   // requested game resolution is supported over here.
-		   || (   _currentState.gameWidth  > (uint)g_context.maxTextureSize
+		   || (   _currentState.gameWidth  > (uint)OpenGLContext.maxTextureSize
-		       || _currentState.gameHeight > (uint)g_context.maxTextureSize)) {
+		       || _currentState.gameHeight > (uint)OpenGLContext.maxTextureSize)) {
 			if (_transactionMode == kTransactionActive) {
 				// Try to setup the old state in case its valid and is
 				// actually different from the new one.
@@ -587,21 +588,21 @@ void OpenGLGraphicsManager::updateScreen() {
 	_backBuffer.enableBlend(Framebuffer::kBlendModeDisabled);
 
 	// First step: Draw the (virtual) game screen.
-	g_context.getActivePipeline()->drawTexture(_gameScreen->getGLTexture(), _gameDrawRect.left, _gameDrawRect.top, _gameDrawRect.width(), _gameDrawRect.height());
+	Pipeline::getActivePipeline()->drawTexture(_gameScreen->getGLTexture(), _gameDrawRect.left, _gameDrawRect.top, _gameDrawRect.width(), _gameDrawRect.height());
 
 	// Second step: Draw the overlay if visible.
 	if (_overlayVisible) {
 		int dstX = (_windowWidth - _overlayDrawRect.width()) / 2;
 		int dstY = (_windowHeight - _overlayDrawRect.height()) / 2;
 		_backBuffer.enableBlend(Framebuffer::kBlendModeTraditionalTransparency);
-		g_context.getActivePipeline()->drawTexture(_overlay->getGLTexture(), dstX, dstY, _overlayDrawRect.width(), _overlayDrawRect.height());
+		Pipeline::getActivePipeline()->drawTexture(_overlay->getGLTexture(), dstX, dstY, _overlayDrawRect.width(), _overlayDrawRect.height());
 	}
 
 	// Third step: Draw the cursor if visible.
 	if (_cursorVisible && _cursor) {
 		_backBuffer.enableBlend(Framebuffer::kBlendModePremultipliedTransparency);
 
-		g_context.getActivePipeline()->drawTexture(_cursor->getGLTexture(),
+		Pipeline::getActivePipeline()->drawTexture(_cursor->getGLTexture(),
 		                         _cursorX - _cursorHotspotXScaled + _shakeOffsetScaled.x,
 		                         _cursorY - _cursorHotspotYScaled + _shakeOffsetScaled.y,
 		                         _cursorWidthScaled, _cursorHeightScaled);
@@ -631,17 +632,17 @@ void OpenGLGraphicsManager::updateScreen() {
 		}
 
 		// Set the OSD transparency.
-		g_context.getActivePipeline()->setColor(1.0f, 1.0f, 1.0f, _osdMessageAlpha / 100.0f);
+		Pipeline::getActivePipeline()->setColor(1.0f, 1.0f, 1.0f, _osdMessageAlpha / 100.0f);
 
 		int dstX = (_windowWidth - _osdMessageSurface->getWidth()) / 2;
 		int dstY = (_windowHeight - _osdMessageSurface->getHeight()) / 2;
 
 		// Draw the OSD texture.
-		g_context.getActivePipeline()->drawTexture(_osdMessageSurface->getGLTexture(),
+		Pipeline::getActivePipeline()->drawTexture(_osdMessageSurface->getGLTexture(),
 		                                           dstX, dstY, _osdMessageSurface->getWidth(), _osdMessageSurface->getHeight());
 
 		// Reset color.
-		g_context.getActivePipeline()->setColor(1.0f, 1.0f, 1.0f, 1.0f);
+		Pipeline::getActivePipeline()->setColor(1.0f, 1.0f, 1.0f, 1.0f);
 
 		if (_osdMessageAlpha <= 0) {
 			delete _osdMessageSurface;
@@ -658,7 +659,7 @@ void OpenGLGraphicsManager::updateScreen() {
 		int dstY = kOSDIconTopMargin;
 
 		// Draw the OSD icon texture.
-		g_context.getActivePipeline()->drawTexture(_osdIconSurface->getGLTexture(),
+		Pipeline::getActivePipeline()->drawTexture(_osdIconSurface->getGLTexture(),
 		                                           dstX, dstY, _osdIconSurface->getWidth(), _osdIconSurface->getHeight());
 	}
 #endif
@@ -1019,15 +1020,15 @@ void OpenGLGraphicsManager::handleResizeImpl(const int width, const int height)
 	// possible and then scale it to the physical display size. This sounds
 	// bad but actually all recent chips should support full HD resolution
 	// anyway. Thus, it should not be a real issue for modern hardware.
-	if (   overlayWidth  > (uint)g_context.maxTextureSize
+	if (   overlayWidth  > (uint)OpenGLContext.maxTextureSize
-	    || overlayHeight > (uint)g_context.maxTextureSize) {
+	    || overlayHeight > (uint)OpenGLContext.maxTextureSize) {
 		const frac_t outputAspect = intToFrac(_windowWidth) / _windowHeight;
 
 		if (outputAspect > (frac_t)FRAC_ONE) {
-			overlayWidth  = g_context.maxTextureSize;
+			overlayWidth  = OpenGLContext.maxTextureSize;
 			overlayHeight = intToFrac(overlayWidth) / outputAspect;
 		} else {
-			overlayHeight = g_context.maxTextureSize;
+			overlayHeight = OpenGLContext.maxTextureSize;
 			overlayWidth  = fracToInt(overlayHeight * outputAspect);
 		}
 	}
@@ -1065,16 +1066,17 @@ void OpenGLGraphicsManager::handleResizeImpl(const int width, const int height)
 	++_screenChangeID;
 }
 
-void OpenGLGraphicsManager::notifyContextCreate(const Graphics::PixelFormat &defaultFormat, const Graphics::PixelFormat &defaultFormatAlpha) {
+void OpenGLGraphicsManager::notifyContextCreate(ContextType type,
-	// Initialize context for use.
+	const Graphics::PixelFormat &defaultFormat,
-	initializeGLContext();
+	const Graphics::PixelFormat &defaultFormatAlpha) {
-
 	// Initialize pipeline.
 	delete _pipeline;
 	_pipeline = nullptr;
 
+	OpenGLContext.initialize(type);
+
 #if !USE_FORCED_GLES
-	if (g_context.shadersSupported) {
+	if (OpenGLContext.shadersSupported) {
 		ShaderMan.notifyCreate();
 		_pipeline = new ShaderPipeline(ShaderMan.query(ShaderManager::kDefault));
 	}
@@ -1086,21 +1088,21 @@ void OpenGLGraphicsManager::notifyContextCreate(const Graphics::PixelFormat &def
 	}
 #endif
 
-	g_context.setPipeline(_pipeline);
+	Pipeline::setPipeline(_pipeline);
 
 	// Disable 3D properties.
 	GL_CALL(glDisable(GL_CULL_FACE));
 	GL_CALL(glDisable(GL_DEPTH_TEST));
 	GL_CALL(glDisable(GL_DITHER));
 
-	g_context.getActivePipeline()->setColor(1.0f, 1.0f, 1.0f, 1.0f);
+	Pipeline::getActivePipeline()->setColor(1.0f, 1.0f, 1.0f, 1.0f);
 
 	// Setup backbuffer state.
 
 	// Default to black as clear color.
 	_backBuffer.setClearColor(0.0f, 0.0f, 0.0f, 0.0f);
 
-	g_context.getActivePipeline()->setFramebuffer(&_backBuffer);
+	Pipeline::getActivePipeline()->setFramebuffer(&_backBuffer);
 
 	// We use a "pack" alignment (when reading from textures) to 4 here,
 	// since the only place where we really use it is the BMP screenshot
@@ -1165,18 +1167,18 @@ void OpenGLGraphicsManager::notifyContextDestroy() {
 #endif
 
 #if !USE_FORCED_GLES
-	if (g_context.shadersSupported) {
+	if (OpenGLContext.shadersSupported) {
 		ShaderMan.notifyDestroy();
 	}
 #endif
 
 	// Destroy rendering pipeline.
-	g_context.setPipeline(nullptr);
+	Pipeline::setPipeline(nullptr);
 	delete _pipeline;
 	_pipeline = nullptr;
 
 	// Rest our context description since the context is gone soon.
-	g_context.reset();
+	OpenGLContext.reset();
 }
 
 Surface *OpenGLGraphicsManager::createSurface(const Graphics::PixelFormat &format, bool wantAlpha, bool wantScaler) {
@@ -1213,7 +1215,7 @@ Surface *OpenGLGraphicsManager::createSurface(const Graphics::PixelFormat &forma
 		}
 	} else if (getGLPixelFormat(format, glIntFormat, glFormat, glType)) {
 		return new Texture(glIntFormat, glFormat, glType, format);
-	} else if (g_context.packedPixelsSupported && format == Graphics::PixelFormat(2, 5, 5, 5, 0, 10, 5, 0, 0)) {
+	} else if (OpenGLContext.packedPixelsSupported && format == Graphics::PixelFormat(2, 5, 5, 5, 0, 10, 5, 0, 0)) {
 		// OpenGL ES does not support a texture format usable for RGB555.
 		// Since SCUMM uses this pixel format for some games (and there is no
 		// hope for this to change anytime soon) we use pixel format
@@ -1244,7 +1246,7 @@ bool OpenGLGraphicsManager::getGLPixelFormat(const Graphics::PixelFormat &pixelF
 		glFormat = GL_RGBA;
 		glType = GL_UNSIGNED_BYTE;
 		return true;
-	} else if (!g_context.packedPixelsSupported) {
+	} else if (!OpenGLContext.packedPixelsSupported) {
 		return false;
 	} else if (pixelFormat == Graphics::PixelFormat(2, 5, 6, 5, 0, 11, 5, 0, 0)) { // RGB565
 		glIntFormat = GL_RGB;

backends/graphics/opengl/opengl-graphics.h

@@ -22,7 +22,6 @@
 #ifndef BACKENDS_GRAPHICS_OPENGL_OPENGL_GRAPHICS_H
 #define BACKENDS_GRAPHICS_OPENGL_OPENGL_GRAPHICS_H
 
-#include "backends/graphics/opengl/opengl-sys.h"
 #include "backends/graphics/opengl/framebuffer.h"
 #include "backends/graphics/windowed.h"
 
@@ -130,28 +129,22 @@ protected:
 	/**
 	 * Whether an GLES or GLES2 context is active.
 	 */
-	bool isGLESContext() const { return g_context.type == kContextGLES || g_context.type == kContextGLES2; }
+	bool isGLESContext() const { return OpenGLContext.type == kContextGLES || OpenGLContext.type == kContextGLES2; }
-
-	/**
-	 * Sets the OpenGL (ES) type the graphics manager shall work with.
-	 *
-	 * This needs to be called at least once (and before ever calling
-	 * notifyContextCreate).
-	 *
-	 * @param type Type of the OpenGL (ES) contexts to be created.
-	 */
-	void setContextType(ContextType type);
 
 	/**
 	 * Notify the manager of a OpenGL context change. This should be the first
 	 * thing to call after you created an OpenGL (ES) context!
 	 *
+	 * @param type               Type of the OpenGL (ES) contexts created.
 	 * @param defaultFormat      The new default format for the game screen
 	 *                           (this is used for the CLUT8 game screens).
 	 * @param defaultFormatAlpha The new default format with an alpha channel
 	 *                           (this is used for the overlay and cursor).
 	 */
-	void notifyContextCreate(const Graphics::PixelFormat &defaultFormat, const Graphics::PixelFormat &defaultFormatAlpha);
+	void notifyContextCreate(
+			ContextType type,
+			const Graphics::PixelFormat &defaultFormat,
+			const Graphics::PixelFormat &defaultFormatAlpha);
 
 	/**
 	 * Notify the manager that the OpenGL context is about to be destroyed.
@@ -300,20 +293,6 @@ private:
 	 */
 	Pipeline *_pipeline;
 
-public:
-	/**
-	 * Query the address of an OpenGL function by name.
-	 *
-	 * This can only be used after a context has been created.
-	 * Please note that this function can return valid addresses even if the
-	 * OpenGL context does not support the function.
-	 *
-	 * @param name The name of the OpenGL function.
-	 * @return An function pointer for the requested OpenGL function or
-	 *         nullptr in case of failure.
-	 */
-	virtual void *getProcAddress(const char *name) const = 0;
-
 protected:
 	/**
 	 * Try to determine the internal parameters for a given pixel format.

backends/graphics/opengl/opengl-sys.h

@@ -1,136 +0,0 @@
-/* ScummVM - Graphic Adventure Engine
- *
- * ScummVM is the legal property of its developers, whose names
- * are too numerous to list here. Please refer to the COPYRIGHT
- * file distributed with this source distribution.
- *
- * 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, either version 3 of the License, or
- * (at your option) any later version.
- *
- * 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 for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- *
- */
-
-#ifndef BACKENDS_GRAPHICS_OPENGL_OPENGL_SYS_H
-#define BACKENDS_GRAPHICS_OPENGL_OPENGL_SYS_H
-
-#include "common/scummsys.h"
-#include "graphics/opengl/system_headers.h"
-
-#include "backends/graphics/opengl/debug.h"
-
-// This is an addition from us to alias ARB shader object extensions to
-// OpenGL (ES) 2.0 style functions. It only works when GLhandleARB and GLuint
-// are type compatible.
-typedef GLuint GLprogram;
-typedef GLuint GLshader;
-
-namespace OpenGL {
-
-enum ContextType {
-	kContextGL,
-	kContextGLES,
-	kContextGLES2
-};
-
-class Pipeline;
-class Framebuffer;
-
-/**
- * Description structure of the OpenGL (ES) context.
- */
-struct Context {
-	/** The type of the active context. */
-	ContextType type;
-
-	/** Whether the context is initialized or not. */
-	bool isInitialized;
-
-	/**
-	 * Reset context.
-	 *
-	 * This marks all extensions as unavailable and clears all function
-	 * pointers.
-	 */
-	void reset();
-
-	/** Helper function for checking the GL version supported by the context. */
-	inline bool isGLVersionOrHigher(int major, int minor) {
-		return ((majorVersion > major) || ((majorVersion == major) && (minorVersion >= minor)));
-	}
-
-	/** The GL version supported by the context. */
-	int majorVersion, minorVersion;
-
-	/** The maximum texture size supported by the context. */
-	GLint maxTextureSize;
-
-	/** Whether GL_ARB_texture_non_power_of_two is available or not. */
-	bool NPOTSupported;
-
-	/** Whether shader support is available or not. */
-	bool shadersSupported;
-
-	/** Whether multi texture support is available or not. */
-	bool multitextureSupported;
-
-	/** Whether FBO support is available or not. */
-	bool framebufferObjectSupported;
-
-	/** Whether packed pixels support is available or not. */
-	bool packedPixelsSupported;
-
-	/** Whether texture coordinate edge clamping is available or not. */
-	bool textureEdgeClampSupported;
-
-	//
-	// Wrapper functionality to handle fixed-function pipelines and
-	// programmable pipelines in the same fashion.
-	//
-
-private:
-	/** Currently active rendering pipeline. */
-	Pipeline *activePipeline;
-
-public:
-	/**
-	 * Set new pipeline.
-	 *
-	 * Client is responsible for any memory management related to pipelines.
-	 *
-	 * @param pipeline Pipeline to activate.
-	 * @return Formerly active pipeline.
-	 */
-	Pipeline *setPipeline(Pipeline *pipeline);
-
-	/**
-	 * Query the currently active rendering pipeline.
-	 */
-	Pipeline *getActivePipeline() const { return activePipeline; }
-};
-
-/**
- * The (active) OpenGL context.
- */
-extern Context g_context;
-
-} // End of namespace OpenGL
-
-#define GL_CALL(x)                 GL_WRAP_DEBUG(x, x)
-#define GL_CALL_SAFE(func, params) \
-	do { \
-		if (g_context.isInitialized) { \
-			GL_CALL(func params); \
-		} \
-	} while (0)
-#define GL_ASSIGN(var, x)          GL_WRAP_DEBUG(var = x, x)
-
-#endif

backends/graphics/opengl/pipelines/clut8.cpp

@@ -20,6 +20,7 @@
  */
 
 #include "backends/graphics/opengl/pipelines/clut8.h"
+#include "backends/graphics/opengl/debug.h"
 #include "backends/graphics/opengl/shader.h"
 #include "backends/graphics/opengl/framebuffer.h"
 

backends/graphics/opengl/pipelines/fixed.cpp

@@ -20,6 +20,7 @@
  */
 
 #include "backends/graphics/opengl/pipelines/fixed.h"
+#include "backends/graphics/opengl/debug.h"
 
 namespace OpenGL {
 
@@ -34,7 +35,7 @@ void FixedPipeline::activateInternal() {
 	GL_CALL(glEnableClientState(GL_TEXTURE_COORD_ARRAY));
 
 #if !USE_FORCED_GLES
-	if (g_context.multitextureSupported) {
+	if (OpenGLContext.multitextureSupported) {
 		GL_CALL(glActiveTexture(GL_TEXTURE0));
 	}
 #endif

backends/graphics/opengl/pipelines/pipeline.cpp

@@ -24,6 +24,8 @@
 
 namespace OpenGL {
 
+Pipeline *Pipeline::activePipeline = nullptr;
+
 Pipeline::Pipeline()
 	: _activeFramebuffer(nullptr), _isActive(false) {
 }
@@ -62,4 +64,18 @@ Framebuffer *Pipeline::setFramebuffer(Framebuffer *framebuffer) {
 	return oldFramebuffer;
 }
 
+Pipeline *Pipeline::setPipeline(Pipeline *pipeline) {
+	Pipeline *oldPipeline = activePipeline;
+	if (oldPipeline) {
+		oldPipeline->deactivate();
+	}
+
+	activePipeline = pipeline;
+	if (activePipeline) {
+		activePipeline->activate();
+	}
+
+	return oldPipeline;
+}
+
 } // End of namespace OpenGL

backends/graphics/opengl/pipelines/pipeline.h

@@ -22,7 +22,8 @@
 #ifndef BACKENDS_GRAPHICS_OPENGL_PIPELINES_PIPELINE_H
 #define BACKENDS_GRAPHICS_OPENGL_PIPELINES_PIPELINE_H
 
-#include "backends/graphics/opengl/opengl-sys.h"
+#include "graphics/opengl/system_headers.h"
+
 #include "backends/graphics/opengl/texture.h"
 
 namespace OpenGL {
@@ -148,6 +149,25 @@ protected:
 
 private:
 	bool _isActive;
+
+	/** Currently active rendering pipeline. */
+	static Pipeline *activePipeline;
+
+public:
+	/**
+	 * Set new pipeline.
+	 *
+	 * Client is responsible for any memory management related to pipelines.
+	 *
+	 * @param pipeline Pipeline to activate.
+	 * @return Formerly active pipeline.
+	 */
+	static Pipeline *setPipeline(Pipeline *pipeline);
+
+	/**
+	 * Query the currently active rendering pipeline.
+	 */
+	static Pipeline *getActivePipeline() { return activePipeline; }
 };
 
 } // End of namespace OpenGL

backends/graphics/opengl/pipelines/shader.cpp

@@ -20,6 +20,7 @@
  */
 
 #include "backends/graphics/opengl/pipelines/shader.h"
+#include "backends/graphics/opengl/debug.h"
 #include "backends/graphics/opengl/shader.h"
 #include "backends/graphics/opengl/framebuffer.h"
 
@@ -50,7 +51,7 @@ void ShaderPipeline::activateInternal() {
 	GL_CALL(glEnableVertexAttribArray(_texCoordAttribLocation));
 	GL_CALL(glEnableVertexAttribArray(_colorAttribLocation));
 
-	if (g_context.multitextureSupported) {
+	if (OpenGLContext.multitextureSupported) {
 		GL_CALL(glActiveTexture(GL_TEXTURE0));
 	}
 

backends/graphics/opengl/shader.cpp

@@ -20,9 +20,9 @@
  */
 
 #include "backends/graphics/opengl/shader.h"
+#include "backends/graphics/opengl/debug.h"
 
 #if !USE_FORCED_GLES
-
 #include "common/textconsole.h"
 #include "common/util.h"
 
@@ -252,7 +252,7 @@ bool Shader::setUniform(const Common::String &name, ShaderUniformValue *value) {
 }
 
 GLshader Shader::compileShader(const char *source, GLenum shaderType) {
-	const GLchar *versionSource = g_context.type == kContextGLES2 ? "#version 100\n" : "#version 110\n";
+	const GLchar *versionSource = OpenGLContext.type == kContextGLES2 ? "#version 100\n" : "#version 110\n";
 	const GLchar *compatSource = shaderType == GL_VERTEX_SHADER ? "" : g_precisionDefines;
 
 	GLshader handle;

backends/graphics/opengl/shader.h

@@ -22,7 +22,7 @@
 #ifndef BACKENDS_GRAPHICS_OPENGL_SHADER_H
 #define BACKENDS_GRAPHICS_OPENGL_SHADER_H
 
-#include "backends/graphics/opengl/opengl-sys.h"
+#include "graphics/opengl/system_headers.h"
 
 #if !USE_FORCED_GLES
 
@@ -30,6 +30,12 @@
 #include "common/hash-str.h"
 #include "common/ptr.h"
 
+// This is an addition from us to alias ARB shader object extensions to
+// OpenGL (ES) 2.0 style functions. It only works when GLhandleARB and GLuint
+// are type compatible.
+typedef GLuint GLprogram;
+typedef GLuint GLshader;
+
 namespace OpenGL {
 
 /**

backends/graphics/opengl/texture.cpp

@@ -20,6 +20,7 @@
  */
 
 #include "backends/graphics/opengl/texture.h"
+#include "backends/graphics/opengl/debug.h"
 #include "backends/graphics/opengl/shader.h"
 #include "backends/graphics/opengl/pipelines/pipeline.h"
 #include "backends/graphics/opengl/pipelines/clut8.h"
@@ -80,7 +81,7 @@ void GLTexture::create() {
 	GL_CALL(glPixelStorei(GL_UNPACK_ALIGNMENT, 1));
 	GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, _glFilter));
 	GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, _glFilter));
-	if (g_context.textureEdgeClampSupported) {
+	if (OpenGLContext.textureEdgeClampSupported) {
 		GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE));
 		GL_CALL(glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE));
 	} else {
@@ -106,7 +107,7 @@ void GLTexture::setSize(uint width, uint height) {
 	const uint oldWidth  = _width;
 	const uint oldHeight = _height;
 
-	if (!g_context.NPOTSupported) {
+	if (!OpenGLContext.NPOTSupported) {
 		_width  = Common::nextHigher2(width);
 		_height = Common::nextHigher2(height);
 	} else {
@@ -734,13 +735,13 @@ void TextureCLUT8GPU::updateGLTexture() {
 
 void TextureCLUT8GPU::lookUpColors() {
 	// Setup pipeline to do color look up.
-	Pipeline *oldPipeline = g_context.setPipeline(_clut8Pipeline);
+	Pipeline *oldPipeline = Pipeline::setPipeline(_clut8Pipeline);
 
 	// Do color look up.
-	g_context.getActivePipeline()->drawTexture(_clut8Texture, _clut8Vertices);
+	Pipeline::getActivePipeline()->drawTexture(_clut8Texture, _clut8Vertices);
 
 	// Restore old state.
-	g_context.setPipeline(oldPipeline);
+	Pipeline::setPipeline(oldPipeline);
 }
 #endif // !USE_FORCED_GLES
 

backends/graphics/opengl/texture.h

@@ -22,7 +22,8 @@
 #ifndef BACKENDS_GRAPHICS_OPENGL_TEXTURE_H
 #define BACKENDS_GRAPHICS_OPENGL_TEXTURE_H
 
-#include "backends/graphics/opengl/opengl-sys.h"
+#include "graphics/opengl/system_headers.h"
+#include "graphics/opengl/context.h"
 
 #include "graphics/pixelformat.h"
 #include "graphics/surface.h"
@@ -405,9 +406,9 @@ public:
 	virtual const GLTexture &getGLTexture() const;
 
 	static bool isSupportedByContext() {
-		return g_context.shadersSupported
+		return OpenGLContext.shadersSupported
-		    && g_context.multitextureSupported
+		    && OpenGLContext.multitextureSupported
-		    && g_context.framebufferObjectSupported;
+		    && OpenGLContext.framebufferObjectSupported;
 	}
 private:
 	void lookUpColors();

backends/graphics/openglsdl/openglsdl-graphics.cpp

@@ -49,8 +49,6 @@ OpenGLSdlGraphicsManager::OpenGLSdlGraphicsManager(SdlEventSource *eventSource,
 
 	// Set up proper SDL OpenGL context creation.
 #if SDL_VERSION_ATLEAST(2, 0, 0)
-	OpenGL::ContextType glContextType;
-
 	// Context version 1.4 is choosen arbitrarily based on what most shader
 	// extensions were written against.
 	enum {
@@ -65,17 +63,17 @@ OpenGLSdlGraphicsManager::OpenGLSdlGraphicsManager(SdlEventSource *eventSource,
 	};
 
 #if USE_FORCED_GL
-	glContextType = OpenGL::kContextGL;
+	_glContextType = OpenGL::kContextGL;
 	_glContextProfileMask = 0;
 	_glContextMajor = DEFAULT_GL_MAJOR;
 	_glContextMinor = DEFAULT_GL_MINOR;
 #elif USE_FORCED_GLES
-	glContextType = OpenGL::kContextGLES;
+	_glContextType = OpenGL::kContextGLES;
 	_glContextProfileMask = SDL_GL_CONTEXT_PROFILE_ES;
 	_glContextMajor = DEFAULT_GLES_MAJOR;
 	_glContextMinor = DEFAULT_GLES_MINOR;
 #elif USE_FORCED_GLES2
-	glContextType = OpenGL::kContextGLES2;
+	_glContextType = OpenGL::kContextGLES2;
 	_glContextProfileMask = SDL_GL_CONTEXT_PROFILE_ES;
 	_glContextMajor = DEFAULT_GLES2_MAJOR;
 	_glContextMinor = DEFAULT_GLES2_MINOR;
@@ -115,12 +113,12 @@ OpenGLSdlGraphicsManager::OpenGLSdlGraphicsManager(SdlEventSource *eventSource,
 
 	if (_glContextProfileMask == SDL_GL_CONTEXT_PROFILE_ES) {
 		if (_glContextMajor >= 2) {
-			glContextType = OpenGL::kContextGLES2;
+			_glContextType = OpenGL::kContextGLES2;
 		} else {
-			glContextType = OpenGL::kContextGLES;
+			_glContextType = OpenGL::kContextGLES;
 		}
 	} else if (_glContextProfileMask == SDL_GL_CONTEXT_PROFILE_CORE) {
-		glContextType = OpenGL::kContextGL;
+		_glContextType = OpenGL::kContextGL;
 
 		// Core profile does not allow legacy functionality, which we use.
 		// Thus we request a standard OpenGL context.
@@ -128,13 +126,11 @@ OpenGLSdlGraphicsManager::OpenGLSdlGraphicsManager(SdlEventSource *eventSource,
 		_glContextMajor = DEFAULT_GL_MAJOR;
 		_glContextMinor = DEFAULT_GL_MINOR;
 	} else {
-		glContextType = OpenGL::kContextGL;
+		_glContextType = OpenGL::kContextGL;
 	}
 #endif
-
-	setContextType(glContextType);
 #else
-	setContextType(OpenGL::kContextGL);
+	_glContextType = OpenGL::kContextGL;
 #endif
 
 	// Retrieve a list of working fullscreen modes
@@ -426,10 +422,6 @@ void OpenGLSdlGraphicsManager::refreshScreen() {
 #endif
 }
 
-void *OpenGLSdlGraphicsManager::getProcAddress(const char *name) const {
-	return SDL_GL_GetProcAddress(name);
-}
-
 void OpenGLSdlGraphicsManager::handleResizeImpl(const int width, const int height) {
 	OpenGLGraphicsManager::handleResizeImpl(width, height);
 	SdlGraphicsManager::handleResizeImpl(width, height);
@@ -550,7 +542,7 @@ bool OpenGLSdlGraphicsManager::setupMode(uint width, uint height) {
 	}
 #endif
 
-	notifyContextCreate(rgba8888, rgba8888);
+	notifyContextCreate(_glContextType, rgba8888, rgba8888);
 	int actualWidth, actualHeight;
 	getWindowSizeFromSdl(&actualWidth, &actualHeight);
 
@@ -617,7 +609,7 @@ bool OpenGLSdlGraphicsManager::setupMode(uint width, uint height) {
 	_lastVideoModeLoad = SDL_GetTicks();
 
 	if (_hwScreen) {
-		notifyContextCreate(rgba8888, rgba8888);
+		notifyContextCreate(_glContextType, rgba8888, rgba8888);
 		handleResize(_hwScreen->w, _hwScreen->h);
 	}
 

backends/graphics/openglsdl/openglsdl-graphics.h

@@ -55,8 +55,6 @@ protected:
 
 	void refreshScreen() override;
 
-	void *getProcAddress(const char *name) const override;
-
 	void handleResizeImpl(const int width, const int height) override;
 
 	bool saveScreenshot(const Common::String &filename) const override;
@@ -66,10 +64,12 @@ private:
 
 #if SDL_VERSION_ATLEAST(2, 0, 0)
 	int _glContextProfileMask, _glContextMajor, _glContextMinor;
+
 	SDL_GLContext _glContext;
 #else
 	uint32 _lastVideoModeLoad;
 #endif
+	OpenGL::ContextType _glContextType;
 
 	uint _lastRequestedWidth;
 	uint _lastRequestedHeight;

backends/graphics3d/android/android-graphics3d.cpp

@@ -171,7 +171,7 @@ void AndroidGraphics3dManager::initSurface() {
 	_screenChangeID = JNI::surface_changeid;
 
 	// Initialize OpenGLES context.
-	OpenGLContext.initialize(OpenGL::kOGLContextGLES2);
+	OpenGLContext.initialize(OpenGL::kContextGLES2);
 	logExtensions();
 	GLESTexture::initGL();
 
@@ -244,7 +244,7 @@ void AndroidGraphics3dManager::deinitSurface() {
 		_touchcontrols_texture->release();
 	}
 
-	OpenGL::ContextGL::destroy();
+	OpenGLContext.reset();
 
 	JNI::deinitSurface();
 }

backends/graphics3d/openglsdl/openglsdl-graphics3d.cpp

@@ -83,7 +83,7 @@ OpenGLSdlGraphics3dManager::OpenGLSdlGraphics3dManager(SdlEventSource *eventSour
 	};
 
 #if USE_FORCED_GLES2
-	_glContextType = OpenGL::kOGLContextGLES2;
+	_glContextType = OpenGL::kContextGLES2;
 	_glContextProfileMask = SDL_GL_CONTEXT_PROFILE_ES;
 	_glContextMajor = DEFAULT_GLES2_MAJOR;
 	_glContextMinor = DEFAULT_GLES2_MINOR;
@@ -123,9 +123,9 @@ OpenGLSdlGraphics3dManager::OpenGLSdlGraphics3dManager(SdlEventSource *eventSour
 
 	if (_glContextProfileMask == SDL_GL_CONTEXT_PROFILE_ES) {
 		// TODO: Support GLES1 for games
-		_glContextType = OpenGL::kOGLContextGLES2;
+		_glContextType = OpenGL::kContextGLES2;
 	} else if (_glContextProfileMask == SDL_GL_CONTEXT_PROFILE_CORE) {
-		_glContextType = OpenGL::kOGLContextGL;
+		_glContextType = OpenGL::kContextGL;
 
 		// Core profile does not allow legacy functionality, which we use.
 		// Thus we request a standard OpenGL context.
@@ -133,11 +133,11 @@ OpenGLSdlGraphics3dManager::OpenGLSdlGraphics3dManager(SdlEventSource *eventSour
 		_glContextMajor = DEFAULT_GL_MAJOR;
 		_glContextMinor = DEFAULT_GL_MINOR;
 	} else {
-		_glContextType = OpenGL::kOGLContextGL;
+		_glContextType = OpenGL::kContextGL;
 	}
 #endif
 #else
-	_glContextType = OpenGL::kOGLContextGL;
+	_glContextType = OpenGL::kContextGL;
 #endif
 }
 
@@ -718,7 +718,7 @@ void OpenGLSdlGraphics3dManager::closeOverlay() {
 	delete _frameBuffer;
 	_frameBuffer = nullptr;
 
-	OpenGL::ContextGL::destroy();
+	OpenGLContext.reset();
 }
 
 int16 OpenGLSdlGraphics3dManager::getOverlayHeight() const {

backends/graphics3d/openglsdl/openglsdl-graphics3d.h

@@ -121,7 +121,7 @@ protected:
 	void deinitializeRenderer();
 #endif
 
-	OpenGL::ContextOGLType _glContextType;
+	OpenGL::ContextType _glContextType;
 
 	bool _supportsFrameBuffer;
 

backends/module.mk

@@ -123,7 +123,6 @@ endif
 # OpenGL specific source files.
 ifdef USE_OPENGL
 MODULE_OBJS += \
-	graphics/opengl/context.o \
 	graphics/opengl/debug.o \
 	graphics/opengl/framebuffer.o \
 	graphics/opengl/opengl-graphics.o \

backends/platform/android/android.cpp

@@ -121,11 +121,6 @@ void checkGlError(const char *expr, const char *file, int line) {
 }
 #endif
 
-void *androidGLgetProcAddress(const char *name) {
-	// This exists since Android 2.3 (API Level 9)
-	return (void *)eglGetProcAddress(name);
-}
-
 OSystem_Android::OSystem_Android(int audio_sample_rate, int audio_buffer_size) :
 	_audio_sample_rate(audio_sample_rate),
 	_audio_buffer_size(audio_buffer_size),
@@ -793,4 +788,11 @@ int OSystem_Android::getGraphicsMode() const {
 	return 0;
 }
 
+#if defined(USE_OPENGL) && defined(USE_GLAD)
+void *OSystem_Android::getOpenGLProcAddress(const char *name) const {
+	// This exists since Android 2.3 (API Level 9)
+	return (void *)eglGetProcAddress(name);
+}
+#endif
+
 #endif

backends/platform/android/android.h

@@ -201,7 +201,10 @@ public:
 	bool setGraphicsMode(int mode, uint flags) override;
 	int getGraphicsMode() const override;
 
-	OpenGL::ContextOGLType getOpenGLType() const override { return OpenGL::kOGLContextGLES2; }
+	OpenGL::ContextType getOpenGLType() const override { return OpenGL::kContextGLES2; }
+#if defined(USE_OPENGL) && defined(USE_GLAD)
+	void *getOpenGLProcAddress(const char *name) const override;
+#endif
 
 #ifdef ANDROID_DEBUG_GL_CALLS
 	bool isRunningInMainThread() { return pthread_self() == _main_thread; }

backends/platform/ios7/ios7_common.h

@@ -112,7 +112,6 @@ bool iOS7_isBigDevice();
 
 void iOS7_buildSharedOSystemInstance();
 void iOS7_main(int argc, char **argv);
-void *iOS7_getProcAddress(const char *name);
 const char *iOS7_getDocumentsDir();
 bool iOS7_touchpadModeEnabled();
 

backends/platform/ios7/ios7_osys_main.cpp

@@ -124,6 +124,12 @@ bool OSystem_iOS7::touchpadModeEnabled() const {
 	return _touchpadModeEnabled;
 }
 
+#if defined(USE_OPENGL) && defined(USE_GLAD)
+void *OSystem_iOS7::getOpenGLProcAddress(const char *name) const {
+	return dlsym(RTLD_SELF, name);
+}
+#endif
+
 int OSystem_iOS7::timerHandler(int t) {
 	DefaultTimerManager *tm = (DefaultTimerManager *)g_system->getTimerManager();
 	tm->handler();
@@ -413,7 +419,3 @@ void iOS7_main(int argc, char **argv) {
 		fclose(newfp);
 	}
 }
-
-void *iOS7_getProcAddress(const char *name) {
-	return dlsym(RTLD_SELF, name);
-}

backends/platform/ios7/ios7_osys_main.h

@@ -143,6 +143,9 @@ public:
 	Graphics::PixelFormat getScreenFormat() const override { return _framebuffer.format; }
 	Common::List<Graphics::PixelFormat> getSupportedFormats() const override;
 #endif
+#if defined(USE_OPENGL) && defined(USE_GLAD)
+	void *getOpenGLProcAddress(const char *name) const override;
+#endif
 
 	PaletteManager *getPaletteManager() override { return this; }
 

backends/platform/sdl/sdl.cpp

@@ -315,12 +315,12 @@ void OSystem_SDL::initBackend() {
 
 #if defined(USE_OPENGL_GAME) || defined(USE_OPENGL_SHADERS)
 void OSystem_SDL::detectOpenGLFeaturesSupport() {
-	_oglType = OpenGL::kOGLContextNone;
+	_oglType = OpenGL::kContextNone;
 	_supportsFrameBuffer = false;
 	_supportsShaders = false;
 #if USE_FORCED_GLES2
 	// Framebuffers and shaders are always available with GLES2
-	_oglType = OpenGL::kOGLContextGLES2;
+	_oglType = OpenGL::kContextGLES2;
 	_supportsFrameBuffer = true;
 	_supportsShaders = true;
 #else
@@ -342,13 +342,13 @@ void OSystem_SDL::detectOpenGLFeaturesSupport() {
 			return;
 		}
 		if (glContextMajor == 2) {
-			_oglType = OpenGL::kOGLContextGLES2;
+			_oglType = OpenGL::kContextGLES2;
 		} else {
 			SDL_DestroyWindow(window);
 			return;
 		}
 	} else {
-		_oglType = OpenGL::kOGLContextGL;
+		_oglType = OpenGL::kContextGL;
 	}
 	SDL_GLContext glContext = SDL_GL_CreateContext(window);
 	if (!glContext) {
@@ -358,7 +358,7 @@ void OSystem_SDL::detectOpenGLFeaturesSupport() {
 
 	OpenGLContext.initialize(_oglType);
 	_supportsFrameBuffer = OpenGLContext.framebufferObjectSupported;
-	_supportsShaders = OpenGLContext.shadersSupported;
+	_supportsShaders = OpenGLContext.enginesShadersSupported;
 	OpenGLContext.reset();
 	SDL_GL_DeleteContext(glContext);
 	SDL_DestroyWindow(window);
@@ -367,7 +367,7 @@ void OSystem_SDL::detectOpenGLFeaturesSupport() {
 	SDL_SetVideoMode(32, 32, 0, SDL_OPENGL);
 	SDL_putenv(const_cast<char *>("SDL_VIDEO_WINDOW_POS=center"));
 	// SDL 1.2 only supports OpenGL
-	_oglType = OpenGL::kOGLContextGL;
+	_oglType = OpenGL::kContextGL;
 	OpenGLContext.initialize(_oglType);
 	_supportsFrameBuffer = OpenGLContext.framebufferObjectSupported;
 	_supportsShaders = OpenGLContext.shadersSupported;
@@ -522,6 +522,12 @@ Common::Array<uint> OSystem_SDL::getSupportedAntiAliasingLevels() const {
 }
 #endif
 
+#if defined(USE_OPENGL) && defined(USE_GLAD)
+void *OSystem_SDL::getOpenGLProcAddress(const char *name) const {
+	return SDL_GL_GetProcAddress(name);
+}
+#endif
+
 void OSystem_SDL::quit() {
 	destroy();
 	exit(0);

backends/platform/sdl/sdl.h

@@ -95,7 +95,10 @@ public:
 
 #if defined(USE_OPENGL_GAME) || defined(USE_OPENGL_SHADERS)
 	Common::Array<uint> getSupportedAntiAliasingLevels() const override;
-	OpenGL::ContextOGLType getOpenGLType() const override { return _oglType; }
+	OpenGL::ContextType getOpenGLType() const override { return _oglType; }
+#endif
+#if defined(USE_OPENGL) && defined(USE_GLAD)
+	void *getOpenGLProcAddress(const char *name) const override;
 #endif
 
 protected:
@@ -137,7 +140,7 @@ protected:
 	void detectOpenGLFeaturesSupport();
 	void detectAntiAliasingSupport();
 
-	OpenGL::ContextOGLType _oglType;
+	OpenGL::ContextType _oglType;
 	bool _supportsFrameBuffer;
 	bool _supportsShaders;
 	Common::Array<uint> _antiAliasLevels;

common/system.h

@@ -745,10 +745,25 @@ public:
 	 *
 	 * @return the OpenGL type of context which is supported.
 	 */
-	virtual OpenGL::ContextOGLType getOpenGLType() const {
+	virtual OpenGL::ContextType getOpenGLType() const {
-		return OpenGL::kOGLContextNone;
+		return OpenGL::kContextNone;
 	}
 
+#if defined(USE_OPENGL) && defined(USE_GLAD)
+	/**
+	 * Query the address of an OpenGL function by name.
+	 *
+	 * This can only be used after a context has been created.
+	 * Please note that this function can return valid addresses even if the
+	 * OpenGL context does not support the function.
+	 *
+	 * @param name The name of the OpenGL function.
+	 * @return An function pointer for the requested OpenGL function or
+	 *         nullptr in case of failure.
+	 */
+	virtual void *getOpenGLProcAddress(const char *name) const { return nullptr; }
+#endif
+
 	/**
 	 * Retrieve a list of all hardware shaders supported by this backend.
 	 *

engines/grim/gfx_opengl_shaders.cpp

@@ -2215,7 +2215,7 @@ Bitmap *GfxOpenGLS::getScreenshot(int w, int h, bool useStored) {
 	Bitmap *bmp;
 
 	if (useStored) {
-		if (OpenGLContext.type == OpenGL::kOGLContextGLES2) {
+		if (OpenGLContext.type == OpenGL::kContextGLES2) {
 			GLuint frameBuffer;
 			glGenFramebuffers(1, &frameBuffer);
 			glBindFramebuffer(GL_FRAMEBUFFER, frameBuffer);

engines/stark/gfx/opengltexture.cpp

@@ -106,7 +106,7 @@ void OpenGlTexture::setLevelCount(uint32 count) {
 		// GLES2 does not allow setting the max provided mipmap level.
 		// It expects all the levels to be provided, which is not the case in TLJ.
 		// FIXME: Enable mipmapping on GLES2
-		if (OpenGLContext.type != OpenGL::kOGLContextGLES2) {
+		if (OpenGLContext.type != OpenGL::kContextGLES2) {
 			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, count - 1);
 
 			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);
@@ -122,7 +122,7 @@ void OpenGlTexture::setLevelCount(uint32 count) {
 void OpenGlTexture::addLevel(uint32 level, const Graphics::Surface *surface, const byte *palette) {
 	assert(level < _levelCount);
 
-	if (level == 0 || OpenGLContext.type != OpenGL::kOGLContextGLES2) {
+	if (level == 0 || OpenGLContext.type != OpenGL::kContextGLES2) {
 		updateLevel(level, surface, palette);
 	}
 }

graphics/opengl/context.cpp

@@ -19,75 +19,62 @@
  *
  */
 
+#define GLAD_GL_IMPLEMENTATION
+
 #include "graphics/opengl/context.h"
 
 #include "common/debug.h"
 #include "common/str.h"
+#include "common/system.h"
 #include "common/textconsole.h"
 #include "common/tokenizer.h"
 
 #include "graphics/opengl/system_headers.h"
 
-#if defined(USE_OPENGL_GAME) || defined(USE_OPENGL_SHADERS)
+#if defined(USE_OPENGL)
 
 #ifdef USE_GLAD
-
+static GLADapiproc loadFunc(const char *name) {
-#ifdef SDL_BACKEND
+	return (GLADapiproc)g_system->getOpenGLProcAddress(name);
-#include "backends/platform/sdl/sdl-sys.h"
-
-static GLADapiproc loadFunc(void *userptr, const char *name) {
-	return (GLADapiproc)SDL_GL_GetProcAddress(name);
 }
-
-#elif defined(__ANDROID__)
-// To keep includes light, don't include EGL here and don't include Android headers
-void *androidGLgetProcAddress(const char *name);
-
-static GLADapiproc loadFunc(void *userptr, const char *name) {
-	return (GLADapiproc)androidGLgetProcAddress(name);
-}
-
-#elif defined(IPHONE_IOS7)
-#include "backends/platform/ios7/ios7_common.h"
-
-static GLADapiproc loadFunc(void *userptr, const char *name) {
-	return (GLADapiproc)iOS7_getProcAddress(name);
-}
-
-#else
-#error Not implemented
-#endif
-
 #endif
 
 namespace Common {
-DECLARE_SINGLETON(OpenGL::ContextGL);
+DECLARE_SINGLETON(OpenGL::Context);
 }
 
 namespace OpenGL {
 
-ContextGL::ContextGL() {
+Context::Context() {
 	reset();
 }
 
-void ContextGL::reset() {
+void Context::reset() {
-	type = kOGLContextNone;
+	type = kContextNone;
 	maxTextureSize = 0;
 
+	majorVersion = 0;
+	minorVersion = 0;
+	glslVersion = 0;
+
 	NPOTSupported = false;
 	shadersSupported = false;
+	enginesShadersSupported = false;
+	multitextureSupported = false;
 	framebufferObjectSupported = false;
+	framebufferObjectMultisampleSupported = false;
+	multisampleMaxSamples = -1;
+	packedPixelsSupported = false;
 	packedDepthStencilSupported = false;
 	unpackSubImageSupported = false;
-	framebufferObjectMultisampleSupported = false;
 	OESDepth24 = false;
-	multisampleMaxSamples = -1;
+	textureEdgeClampSupported = false;
 }
 
-void ContextGL::initialize(ContextOGLType contextType) {
+void Context::initialize(ContextType contextType) {
 	// Initialize default state.
 	reset();
-	if (contextType == kOGLContextNone) {
+	if (contextType == kContextNone) {
 		return;
 	}
 
@@ -95,12 +82,16 @@ void ContextGL::initialize(ContextOGLType contextType) {
 
 #ifdef USE_GLAD
 	switch (type) {
-	case kOGLContextGL:
+	case kContextGL:
-		gladLoadGLUserPtr(loadFunc, this);
+		gladLoadGL(loadFunc);
 		break;
 
-	case kOGLContextGLES2:
+	case kContextGLES:
-		gladLoadGLES2UserPtr(loadFunc, this);
+		gladLoadGLES1(loadFunc);
+		break;
+
+	case kContextGLES2:
+		gladLoadGLES2(loadFunc);
 		break;
 
 	default:
@@ -108,6 +99,42 @@ void ContextGL::initialize(ContextOGLType contextType) {
 	}
 #endif
 
+	const char *verString = (const char *)glGetString(GL_VERSION);
+	debug(5, "OpenGL version: %s", verString);
+
+	if (type == kContextGL) {
+		// OpenGL version number is either of the form major.minor or major.minor.release,
+		// where the numbers all have one or more digits
+		if (sscanf(verString, "%d.%d", &majorVersion, &minorVersion) != 2) {
+			majorVersion = minorVersion = 0;
+			warning("Could not parse GL version '%s'", verString);
+		}
+	} else if (type == kContextGLES) {
+		// The form of the string is "OpenGL ES-<profile> <major>.<minor>",
+		// where <profile> is either "CM" (Common) or "CL" (Common-Lite),
+		// and <major> and <minor> are integers.
+		char profile[3];
+		if (sscanf(verString, "OpenGL ES-%2s %d.%d", profile,
+					&majorVersion, &minorVersion) != 3) {
+			majorVersion = minorVersion = 0;
+			warning("Could not parse GL ES version '%s'", verString);
+		}
+	} else if (type == kContextGLES2) {
+		// The version is of the form
+		// OpenGL<space>ES<space><version number><space><vendor-specific information>
+		// version number format is not defined
+		// There is only OpenGL ES 2.0 anyway
+		if (sscanf(verString, "OpenGL ES %d.%d", &majorVersion, &minorVersion) != 2) {
+			minorVersion = 0;
+			if (sscanf(verString, "OpenGL ES %d ", &majorVersion) != 1) {
+				majorVersion = 0;
+				warning("Could not parse GL ES 2 version '%s'", verString);
+			}
+		}
+	}
+
+	glslVersion = getGLSLVersion();
+
 	// Obtain maximum texture size.
 	glGetIntegerv(GL_MAX_TEXTURE_SIZE, (GLint *)&maxTextureSize);
 	debug(5, "OpenGL maximum texture size: %d", maxTextureSize);
@@ -135,8 +162,12 @@ void ContextGL::initialize(ContextOGLType contextType) {
 			ARBVertexShader = true;
 		} else if (token == "GL_ARB_fragment_shader") {
 			ARBFragmentShader = true;
+		} else if (token == "GL_ARB_multitexture") {
+			multitextureSupported = true;
 		} else if (token == "GL_ARB_framebuffer_object") {
 			framebufferObjectSupported = true;
+		} else if (token == "GL_EXT_packed_pixels" || token == "GL_APPLE_packed_pixels") {
+			packedPixelsSupported = true;
 		} else if (token == "GL_EXT_packed_depth_stencil" || token == "GL_OES_packed_depth_stencil") {
 			packedDepthStencilSupported = true;
 		} else if (token == "GL_EXT_unpack_subimage") {
@@ -147,19 +178,22 @@ void ContextGL::initialize(ContextOGLType contextType) {
 			EXTFramebufferBlit = true;
 		} else if (token == "GL_OES_depth24") {
 			OESDepth24 = true;
+		} else if (token == "GL_SGIS_texture_edge_clamp") {
+			textureEdgeClampSupported = true;
 		}
-
 	}
 
-	int glslVersion = getGLSLVersion();
+	if (type == kContextGLES2) {
-	debug(5, "OpenGL GLSL version: %d", glslVersion);
-
-	if (type == kOGLContextGLES2) {
 		// GLES2 always has (limited) NPOT support.
 		NPOTSupported = true;
 
 		// GLES2 always has shader support.
 		shadersSupported = true;
+		// GLES2 should always have GLSL ES 1.00 support but let's make sure
+		enginesShadersSupported = (glslVersion >= 100);
+
+		// GLES2 always has multi texture support.
+		multitextureSupported = true;
 
 		// GLES2 always has FBO support.
 		framebufferObjectSupported = true;
@@ -167,8 +201,42 @@ void ContextGL::initialize(ContextOGLType contextType) {
 		// ScummVM does not support multisample FBOs with GLES2 for now
 		framebufferObjectMultisampleSupported = false;
 		multisampleMaxSamples = -1;
-	} else {
+
-		shadersSupported = ARBShaderObjects && ARBShadingLanguage100 && ARBVertexShader && ARBFragmentShader && glslVersion >= 120;
+		packedPixelsSupported = true;
+		textureEdgeClampSupported = true;
+		debug(5, "OpenGL: GLES2 context initialized");
+	} else if (type == kContextGLES) {
+		// GLES doesn't support shaders natively
+		// We don't do any aliasing in our code and expect standard OpenGL functions but GLAD does it
+		// So if we use GLAD we can check for ARB extensions and expect a GLSL of 1.00
+#ifdef USE_GLAD
+		shadersSupported = ARBShaderObjects && ARBShadingLanguage100 && ARBVertexShader && ARBFragmentShader;
+		glslVersion = 100;
+#endif
+		// We don't expect GLES to support shaders recent enough for engines
+
+		// ScummVM does not support multisample FBOs with GLES for now
+		framebufferObjectMultisampleSupported = false;
+		multisampleMaxSamples = -1;
+
+		packedPixelsSupported = true;
+		textureEdgeClampSupported = true;
+		debug(5, "OpenGL: GLES context initialized");
+	} else if (type == kContextGL) {
+		shadersSupported = glslVersion >= 100;
+
+		// We don't do any aliasing in our code and expect standard OpenGL functions but GLAD does it
+		// So if we use GLAD we can check for ARB extensions and expect a GLSL of 1.00
+#ifdef USE_GLAD
+		if (!shadersSupported) {
+			shadersSupported = ARBShaderObjects && ARBShadingLanguage100 && ARBVertexShader && ARBFragmentShader;
+			if (shadersSupported) {
+				glslVersion = 100;
+			}
+		}
+#endif
+		// In GL mode engines need GLSL 1.20
+		enginesShadersSupported = glslVersion >= 120;
 
 		// Desktop GL always has unpack sub-image support
 		unpackSubImageSupported = true;
@@ -178,31 +246,50 @@ void ContextGL::initialize(ContextOGLType contextType) {
 		if (framebufferObjectMultisampleSupported) {
 			glGetIntegerv(GL_MAX_SAMPLES, (GLint *)&multisampleMaxSamples);
 		}
-	}
 
-	// Log context type.
+		// OpenGL 1.2 and later always has packed pixels and texture edge clamp support
-	switch (type) {
+		if (isGLVersionOrHigher(1, 2)) {
-		case kOGLContextNone:
+			packedPixelsSupported = true;
-			/* Shouldn't happen */
+			textureEdgeClampSupported = true;
-			break;
+		}
-		case kOGLContextGL:
+		debug(5, "OpenGL: GL context initialized");
-			debug(5, "OpenGL: GL context initialized");
+	} else {
-			break;
+		warning("OpenGL: Unknown context initialized");
-
-		case kOGLContextGLES2:
-			debug(5, "OpenGL: GLES2 context initialized");
-			break;
 	}
 
 	// Log features supported by GL context.
+	debug(5, "OpenGL vendor: %s", glGetString(GL_VENDOR));
+	debug(5, "OpenGL renderer: %s", glGetString(GL_RENDERER));
+	debug(5, "OpenGL: version %d.%d", majorVersion, minorVersion);
+	debug(5, "OpenGL: GLSL version: %d", glslVersion);
+	debug(5, "OpenGL: Max texture size: %d", maxTextureSize);
 	debug(5, "OpenGL: NPOT texture support: %d", NPOTSupported);
 	debug(5, "OpenGL: Shader support: %d", shadersSupported);
+	debug(5, "OpenGL: Multitexture support: %d", multitextureSupported);
 	debug(5, "OpenGL: FBO support: %d", framebufferObjectSupported);
+	debug(5, "OpenGL: Multisample FBO support: %d", framebufferObjectMultisampleSupported);
+	debug(5, "OpenGL: Multisample max number: %d", multisampleMaxSamples);
+	debug(5, "OpenGL: Packed pixels support: %d", packedPixelsSupported);
 	debug(5, "OpenGL: Packed depth stencil support: %d", packedDepthStencilSupported);
 	debug(5, "OpenGL: Unpack subimage support: %d", unpackSubImageSupported);
+	debug(5, "OpenGL: OpenGL ES depth 24 support: %d", OESDepth24);
+	debug(5, "OpenGL: Texture edge clamping support: %d", textureEdgeClampSupported);
 }
 
-int ContextGL::getGLSLVersion() const {
+int Context::getGLSLVersion() const {
+#if USE_FORCED_GLES
+	return 0;
+#else
+	// No shader support in GLES
+	if (type == kContextGLES) {
+		return 0;
+	}
+
+	// No shader support in OpenGL 1.x
+	if (type == kContextGL && !isGLVersionOrHigher(2, 0)) {
+		return 0;
+	}
+
 	const char *glslVersionString = (const char *)glGetString(GL_SHADING_LANGUAGE_VERSION);
 	if (!glslVersionString) {
 		warning("Could not get GLSL version");
@@ -210,7 +297,7 @@ int ContextGL::getGLSLVersion() const {
 	}
 
 	const char *glslVersionFormat;
-	if (type == kOGLContextGL) {
+	if (type == kContextGL) {
 		glslVersionFormat = "%d.%d";
 	} else {
 		glslVersionFormat = "OpenGL ES GLSL ES %d.%d";
@@ -223,6 +310,7 @@ int ContextGL::getGLSLVersion() const {
 	}
 
 	return glslMajorVersion * 100 + glslMinorVersion;
+#endif
 }
 
 } // End of namespace OpenGL

graphics/opengl/context.h

@@ -26,20 +26,19 @@
 
 namespace OpenGL {
 
-enum ContextOGLType {
+enum ContextType {
-	kOGLContextNone,
+	kContextNone,
-	kOGLContextGL,
+	kContextGL,
-	kOGLContextGLES2
+	kContextGLES,
+	kContextGLES2
 };
 
 /**
  * Description structure of the OpenGL (ES) context.
- *
- * This class is based on LordHoto's OpenGL backend for ScummVM
  */
-class ContextGL : public Common::Singleton<ContextGL> {
+class Context : public Common::Singleton<Context> {
 public:
-	ContextGL();
+	Context();
 
 	/**
 	 * Initialize the context description from currently active context.
@@ -47,7 +46,7 @@ public:
 	 * The extensions and features are marked as available according
 	 * to the current context capabilities.
 	 */
-	void initialize(ContextOGLType contextType);
+	void initialize(ContextType contextType);
 
 	/**
 	 * Reset context.
@@ -57,7 +56,18 @@ public:
 	void reset();
 
 	/** The type of the active context. */
-	ContextOGLType type;
+	ContextType type;
+
+	/** Helper function for checking the GL version supported by the context. */
+	inline bool isGLVersionOrHigher(int major, int minor) const {
+		return ((majorVersion > major) || ((majorVersion == major) && (minorVersion >= minor)));
+	}
+
+	/** The GL version supported by the context. */
+	int majorVersion, minorVersion;
+
+	/** The GLSL version supported by the context */
+	int glslVersion;
 
 	/** The maximum texture size supported by the context. */
 	int maxTextureSize;
@@ -68,6 +78,12 @@ public:
 	/** Whether shader support is available or not. */
 	bool shadersSupported;
 
+	/** Whether shader support is good enough for engines or not. */
+	bool enginesShadersSupported;
+
+	/** Whether multi texture support is available or not. */
+	bool multitextureSupported;
+
 	/** Whether FBO support is available or not. */
 	bool framebufferObjectSupported;
 
@@ -80,6 +96,9 @@ public:
 	 */
 	int multisampleMaxSamples;
 
+	/** Whether packed pixels support is available or not. */
+	bool packedPixelsSupported;
+
 	/** Whether packing the depth and stencil buffers is possible or not. */
 	bool packedDepthStencilSupported;
 
@@ -89,12 +108,20 @@ public:
 	/** Whether depth component 24 is supported or not */
 	bool OESDepth24;
 
+	/** Whether texture coordinate edge clamping is available or not. */
+	bool textureEdgeClampSupported;
+
+private:
+	/**
+	 * Returns the native GLSL version supported by the driver.
+	 * This does NOT take shaders ARB extensions into account.
+	 */
 	int getGLSLVersion() const;
 };
 
 } // End of namespace OpenGL
 
 /** Shortcut for accessing the active OpenGL context. */
-#define OpenGLContext OpenGL::ContextGL::instance()
+#define OpenGLContext OpenGL::Context::instance()
 
 #endif

graphics/opengl/shader.cpp

@@ -133,7 +133,7 @@ static GLuint createDirectShader(const char *shaderSource, GLenum shaderType, co
 }
 
 static GLuint createCompatShader(const char *shaderSource, GLenum shaderType, const Common::String &name) {
-	const GLchar *versionSource = OpenGLContext.type == kOGLContextGLES2 ? "#version 100\n" : "#version 120\n";
+	const GLchar *versionSource = OpenGLContext.type == kContextGLES2 ? "#version 100\n" : "#version 120\n";
 	const GLchar *compatSource =
 			shaderType == GL_VERTEX_SHADER ? compatVertex : compatFragment;
 	const GLchar *shaderSources[] = {

graphics/renderer.cpp

@@ -93,7 +93,7 @@ uint32 Renderer::getAvailableTypes() {
 		/* Backend either support OpenGL or OpenGL ES(2) */
 #if defined(USE_OPENGL_GAME)
 		/* OpenGL classic is compiled in, check if hardware supports it */
-		if (g_system->getOpenGLType() == OpenGL::kOGLContextGL) {
+		if (g_system->getOpenGLType() == OpenGL::kContextGL) {
 			available |= kRendererTypeOpenGL;
 		}
 #endif