SDL3 , cannot render anything

SDL Development
1

Good day, i 'd like to switch from glfw to sdl3, i have created an app and set the opengl version to 3.1 , everything works fine. But when i set the major and minor version to 4.5 , or anything else which is not 3.1 , i cannot see any longer the vertex array being drawn. I am sure its something related to vertex arrays rendering becasue the glclear screen still works.
What am I doing wrong ?
thanks

2
  1. show a MRE
  2. what platform is being used? (Windows, Linux, etc.)
  3. how do you fill OpenGL function pointers? (glew, glad etc.)
3

show a MRE

1 Like
4 
		void InitSDL(uint32_t flags)
		{

			// Initialize SDL

			if (!SDL_Init(SDL_INIT_VIDEO))
			{
				vml::os::Message::Error("SDL could not initialize! SDL Error : ", SDL_GetError());
			}
			else
			{
				// get flags

				Flags = flags;

				vml::utils::Logger::GetInstance()->Info("SDL API", "Initting SDL : In progress...");
				
				// Use OpenGL 3.1 core
			//	SDL_GL_SetAttribute(SDL_GL_ACCELERATED_VISUAL, 1);
				SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
				SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 1);
				SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);

				// Also request a depth buffer

				SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
				SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);

				// Create window

				GlWindow = SDL_CreateWindow("SDL Tutorial", ScreenWidth, ScreenHeight, SDL_WINDOW_OPENGL );

				if (!GlWindow)
					vml::os::Message::Error("SDL : ", "couldn't set up video mode");

				// check if window is at fullscreen or not

				bool maximized  = vml::utils::bits32::Get(Flags, MAXIMIZED);
				bool fullscreen = vml::utils::bits32::Get(Flags, FULLSCREEN);

				if (maximized && fullscreen)
					vml::os::Message::Error("SDL : ", "couldn't set up screen mode choose fullscreen or windowed");

				if ( maximized && !fullscreen )
				{
					SDL_SetWindowResizable(GlWindow, true);
					SDL_MaximizeWindow(GlWindow);
				}

				if (fullscreen && !maximized)
				{
					SDL_SetWindowResizable(GlWindow, true);
					SDL_SetWindowFullscreen(GlWindow, true);
				}

				// exit on esc pressed ?

				ExitOnEsc = false;
				if (vml::utils::bits32::Get(Flags, EXIT_ON_ESC))
					ExitOnEsc = true;

				// create opengl window

					//Create context
					
					GlContext = SDL_GL_CreateContext(GlWindow);

					if (!GlContext)
					{
						vml::os::Message::Error("OpenGL context could not be created! SDL Error: %s\n", SDL_GetError());
					}
					else
					{

						//Initialize GLEW

						glewExperimental = GL_TRUE;

						GLenum glewError = glewInit();

						if (glewError != GLEW_OK)
							vml::os::Message::Error("Error initializing GLEW! %s\n", glewGetErrorString(glewError));

						//Use Vsync

						if (!SDL_GL_SetSwapInterval(1))
							vml::os::Message::Error("Warning: Unable to set VSync! SDL Error: %s\n", SDL_GetError());

						//Initialize OpenGL

						if (!initGL())
							vml::os::Message::Error("Unable to initialize OpenGL!\n");
						
					}
					

				vml::utils::Logger::GetInstance()->Info("SDL API", "Initting SDL : Done");

			}
		}

This is the initialisation part, windows 10 paltform, opengl pointers are filled trhough glew ( yes they work )

5

according to lazyfoo’s tutorials

"Also, I get e-mails of how this code is broken because if you set the version to 3.2+ it won’t work because it doesn’t use vertex array objects (or VAOs). The thing is this code works fine for version 3.1 core, which it is designed to be. However, OpenGL 3.2+ requires you create a VAO. Fortunately I cover VAOs in the OpenGL tutorial. "