GL: Cache current GL context. Issue #262.

src/glcontext_egl.cpp

@@ -254,6 +254,7 @@ EGL_IMPORT
 
 		success = eglMakeCurrent(m_display, m_surface, m_surface, m_context);
 		BGFX_FATAL(success, Fatal::UnableToInitialize, "Failed to set context.");
+		m_current = NULL;
 
 		eglSwapInterval(m_display, 0);
 
@@ -311,20 +312,24 @@ EGL_IMPORT
 
 	void GlContext::swap(SwapChainGL* _swapChain)
 	{
+		makeCurrent(_swapChain);
+
 		if (NULL == _swapChain)
 		{
-			eglMakeCurrent(m_display, m_surface, m_surface, m_context);
 			eglSwapBuffers(m_display, m_surface);
 		}
 		else
 		{
-			_swapChain->makeCurrent();
 			_swapChain->swapBuffers();
 		}
 	}
 
 	void GlContext::makeCurrent(SwapChainGL* _swapChain)
 	{
+		if (m_current != _swapChain)
+		{
+			m_current = _swapChain;
+
 			if (NULL == _swapChain)
 			{
 				eglMakeCurrent(m_display, m_surface, m_surface, m_context);
@@ -334,6 +339,7 @@ EGL_IMPORT
 				_swapChain->makeCurrent();
 			}
 		}
+	}
 
 	void GlContext::import()
 	{

src/glcontext_egl.h

@@ -17,7 +17,8 @@ namespace bgfx
 	struct GlContext
 	{
 		GlContext()
-			: m_context(NULL)
+			: m_current(NULL)
+			, m_context(NULL)
 			, m_display(NULL)
 			, m_surface(NULL)
 		{
@@ -41,6 +42,7 @@ namespace bgfx
 		}
 
 		void* m_eglLibrary;
+		SwapChainGL* m_current;
 		EGLConfig  m_config;
 		EGLContext m_context;
 		EGLDisplay m_display;

src/glcontext_glx.cpp

@@ -175,6 +175,7 @@ namespace bgfx
 		import();
 
 		glXMakeCurrent( (::Display*)g_bgfxX11Display, (::Window)g_bgfxX11Window, m_context);
+		m_current = NULL;
 
 		glXSwapIntervalEXT = (PFNGLXSWAPINTERVALEXTPROC)glXGetProcAddress( (const GLubyte*)"glXSwapIntervalEXT");
 		if (NULL != glXSwapIntervalEXT)
@@ -248,20 +249,24 @@ namespace bgfx
 
 	void GlContext::swap(SwapChainGL* _swapChain)
 	{
+		makeCurrent(_swapChain);
+
 		if (NULL == _swapChain)
 		{
-			glXMakeCurrent( (::Display*)g_bgfxX11Display, (::Window)g_bgfxX11Window, m_context);
 			glXSwapBuffers( (::Display*)g_bgfxX11Display, (::Window)g_bgfxX11Window);
 		}
 		else
 		{
-			_swapChain->makeCurrent();
 			_swapChain->swapBuffers();
 		}
 	}
 
 	void GlContext::makeCurrent(SwapChainGL* _swapChain)
 	{
+		if (m_current != _swapChain)
+		{
+			m_current = _swapChain;
+
 			if (NULL == _swapChain)
 			{
 				glXMakeCurrent( (::Display*)g_bgfxX11Display, (::Window)g_bgfxX11Window, m_context);
@@ -271,6 +276,7 @@ namespace bgfx
 				_swapChain->makeCurrent();
 			}
 		}
+	}
 
 	void GlContext::import()
 	{

src/glcontext_glx.h

@@ -18,7 +18,8 @@ namespace bgfx
 	struct GlContext
 	{
 		GlContext()
-			: m_context(0)
+			: m_current(NULL)
+			, m_context(0)
 			, m_visualInfo(NULL)
 		{
 		}
@@ -40,6 +41,7 @@ namespace bgfx
 			return 0 != m_context;
 		}
 
+		SwapChainGL* m_current;
 		GLXContext m_context;
 		XVisualInfo* m_visualInfo;
 	};

src/glcontext_wgl.cpp

@@ -259,6 +259,7 @@ namespace bgfx
 
 			int result = wglMakeCurrent(m_hdc, m_context);
 			BGFX_FATAL(0 != result, Fatal::UnableToInitialize, "wglMakeCurrent failed!");
+			m_current = NULL;
 
 			if (NULL != wglSwapIntervalEXT)
 			{
@@ -316,8 +317,29 @@ namespace bgfx
 		BX_DELETE(g_allocator, _swapChain);
 	}
 
+	void GlContext::swap(SwapChainGL* _swapChain)
+	{
+		makeCurrent(_swapChain);
+
+		if (NULL == _swapChain)
+		{
+			if (NULL != g_bgfxHwnd)
+			{
+				SwapBuffers(m_hdc);
+			}
+		}
+		else
+		{
+			_swapChain->swapBuffers();
+		}
+	}
+
 	void GlContext::makeCurrent(SwapChainGL* _swapChain)
 	{
+		if (m_current != _swapChain)
+		{
+			m_current = _swapChain;
+
 			if (NULL == _swapChain)
 			{
 				wglMakeCurrent(m_hdc, m_context);
@@ -329,22 +351,6 @@ namespace bgfx
 				_swapChain->makeCurrent();
 			}
 		}
-
-	void GlContext::swap(SwapChainGL* _swapChain)
-	{
-		if (NULL == _swapChain)
-		{
-			if (NULL != g_bgfxHwnd)
-			{
-				wglMakeCurrent(m_hdc, m_context);
-				SwapBuffers(m_hdc);
-			}
-		}
-		else
-		{
-			_swapChain->makeCurrent();
-			_swapChain->swapBuffers();
-		}
 	}
 
 	void GlContext::import()

src/glcontext_wgl.h

@@ -61,7 +61,8 @@ typedef void (APIENTRYP PFNGLSTENCILOPPROC) (GLenum fail, GLenum zfail, GLenum z
 	struct GlContext
 	{
 		GlContext()
-			: m_opengl32dll(NULL)
+			: m_current(NULL)
+			, m_opengl32dll(NULL)
 			, m_context(NULL)
 			, m_hdc(NULL)
 		{
@@ -87,6 +88,7 @@ typedef void (APIENTRYP PFNGLSTENCILOPPROC) (GLenum fail, GLenum zfail, GLenum z
 		int32_t m_contextAttrs[9];
 		int m_pixelFormat;
 		PIXELFORMATDESCRIPTOR m_pfd;
+		SwapChainGL* m_current;
 		void* m_opengl32dll;
 		HGLRC m_context;
 		HDC m_hdc;