SDL3 WebGPU Extension

This is an extension for the great SDL3 library for using it with WebGPU native. It was written as part of the Learn WebGPU for native C++ tutorial series.

Table of Contents

• Overview
• Usage
• Example
• License

Overview

This extension simply provides the following function:

WGPUSurface SDL_GetWGPUSurface(WGPUInstance instance, SDL_Window* window);

Given an SDL window, SDL_GetWGPUSurface returns a WebGPU surface that corresponds to the window's backend. This is a process that is highly platform-specific, which is why I believe it belongs to SDL.

Usage

Your project must link to an implementation of WebGPU (providing webgpu.h) and of course to SDL. Then:

Option A If you use CMake, you can simply include this project as a subdirectory with add_subdirectory(sdl3webgpu) (see the content of CMakeLists.txt).

Option B Just copy sdl3webgpu.h and sdl3webgpu.c to your project's source tree. On MacOS, you must add the compile option -x objective-c and the link libraries -framework Cocoa, -framework CoreVideo, -framework IOKit, and -framework QuartzCore. For iOS, do similarly but use -framework UIKit instead of -framework Cocoa.

Example

Thanks to this extension it is possible to simply write a fully cross-platform WebGPU hello world:

#define SDL_MAIN_HANDLED
#include "sdl3webgpu.h"
#include <SDL3/SDL.h>
#include <webgpu/webgpu.h>
#include <stdio.h>

int main(int argc, char* argv[]) {
	(void)argc;
	(void)argv;

	// Init WebGPU
	WGPUInstance instance = wgpuCreateInstance(NULL);

	// Init SDL
	SDL_Init(SDL_INIT_VIDEO);
	SDL_Window *window = SDL_CreateWindow("Learn WebGPU", 640, 480, 0);

	// Here we create our WebGPU surface from the window!
	WGPUSurface surface = SDL_GetWGPUSurface(instance, window);
	printf("surface = %p", (void*)surface);

	// Wait for close
	SDL_Event event;
	int running = 1;
	while (running)
		while (SDL_PollEvent(&event))
			if (event.type == SDL_EVENT_QUIT)
				running = 0;
	// Terminate SDL
	SDL_DestroyWindow(window);
	SDL_Quit();

	return 0;
}

NB The linking process depends on the implementation of WebGPU that you are using. You can find detailed instructions for the wgpu-native implementation in this Hello WebGPU chapter. You may also check out examples/CMakeLists.txt.

License

See LICENSE.txt.