OPENGL: Add functionality to query OpenGL functions on runtime.

This can and will be used for future extension usage support.

Tizen changes have been untested.

2 files changed, 21 insertions, 0 deletions

diff --git a/backends/graphics/opengl/opengl-graphics.h b/backends/graphics/opengl/opengl-graphics.h
index 2a03b878ce..f83c9537ec 100644
--- a/backends/graphics/opengl/opengl-graphics.h
+++ b/backends/graphics/opengl/opengl-graphics.h
@@ -286,6 +286,21 @@ private:
 	 */
 	void initializeGLExtensions();
 
+protected:
+	/**
+	 * 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;
+
+private:
 	/**
 	 * Try to determine the internal parameters for a given pixel format.
 	 *
diff --git a/backends/graphics/opengl/opengl-sys.h b/backends/graphics/opengl/opengl-sys.h
index 4e21894380..f4d8488259 100644
--- a/backends/graphics/opengl/opengl-sys.h
+++ b/backends/graphics/opengl/opengl-sys.h
@@ -54,4 +54,10 @@ using namespace Tizen::Graphics::Opengl;
 #include <GL/gl.h>
 #endif
 
+#ifdef SDL_BACKEND
+#define GLCALLCONV APIENTRY
+#else
+#define GLCALLCONV
+#endif
+
 #endif