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POOpenGL window with SDL not showing
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  1. POOpenGL window with SDL not showing
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    copied!<p>I'm working on a program with OpenGL/SDL, but the window won't draw. The window's entry appears in the taskbar and the alt+tab menu, but no thumbnail is shown. When I click it, it's marked as active, but nothing changes onscreen. </p> <p>I can verify that <code>glClear(GL_COLOR_BUFFER_BIT)</code> and <code>SDL_GL_SwapBuffers()</code> are being called from my render loop, and that <code>SDL_SetVideoMode</code> is succeeding, but it still won't render. It's not a shared library issue, since other SDL/GL apps work fine. </p> <p>Any ideas?</p> <p>EDIT:</p> <p>Here's the graphics initialization:</p> <pre><code>void GraphicsManager::initGraphics() { // Access prefs PreferencesManager* prefMgr = PreferencesManager::getInstance(); int width = prefMgr-&gt;getIntKey("res_width"); int height = prefMgr-&gt;getIntKey("res_height"); if(SDL_InitSubSystem(SDL_INIT_VIDEO) != 0) { fprintf(stderr, "Cannot initialize SDL video!\n"); exit(1); } SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1); SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 8); SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 8); SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 8); SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, 8); m_screen = SDL_SetVideoMode(width, height, 0, SDL_OPENGL); if(!m_screen) { fprintf(stderr, "Error: Invalid screen pointer\n"); exit(2); } SDL_ShowCursor(SDL_DISABLE); // Setup OpenGL stuffs glDisable(GL_DEPTH_TEST); // We're only using 2D glClearColor(0.0, 0.0, 0.0, 0.0); glViewport(0.0, 0.0, width, height); glClear(GL_COLOR_BUFFER_BIT); glMatrixMode(GL_PROJECTION); glLoadIdentity(); glOrtho(0.0, width, height, 0.0, -1.0f, 1.0f); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glEnable(GL_TEXTURE_2D); glClear(GL_COLOR_BUFFER_BIT); SDL_GL_SwapBuffers(); // Init FPS stuff m_avgFps = 60.0f; m_lastUpdate = SDL_GetTicks(); } </code></pre> <p>Here's my main loop:</p> <pre><code>while(stateMgr-&gt;getState() != GS_QUIT) { // Process input events inputMgr-&gt;processEvents(); // Update the current system mode stateMgr-&gt;update(); // Update GUI state guiMgr-&gt;update(); // Render gfxMgr-&gt;render(); //char buf[16]; //snprintf(buf, 16, "FPS: %4.2f", gfxMgr-&gt;getFramerate()); //testWindow-&gt;getChild("TestRoot/Framerate")-&gt;setText(buf); SDL_Delay(10); } </code></pre> <p>And here's the render function:</p> <pre><code>void GraphicsManager::render() { std::list&lt;IRenderCallback*&gt;::iterator rci; // Clear the screen glClear(GL_COLOR_BUFFER_BIT); // Run render callbacks /*for(rci=m_renderCallbacks.begin();rci != m_renderCallbacks.end();rci++) { (*rci)-&gt;preRender(); } // Iterate through all renderables and render them std::list&lt;Renderable*&gt;::iterator i; for(i=m_renderables.begin();i != m_renderables.end();i++) { (*i)-&gt;render(); } // Run render callbacks for(rci=m_renderCallbacks.begin();rci != m_renderCallbacks.end();rci++) { (*rci)-&gt;preFlip(); }*/ // Flip the buffers SDL_GL_SwapBuffers(); // Update FPS stuff Uint32 now = SDL_GetTicks(); Uint32 timeTaken = now - m_lastUpdate; m_lastUpdate = now; double seconds = (double)timeTaken / 1000.0f; m_avgFps = (1.0f / seconds); // Run render callbacks for(rci=m_renderCallbacks.begin();rci != m_renderCallbacks.end();rci++) { (*rci)-&gt;postRender(); } } </code></pre>
 

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