diff --git a/CMakeLists.txt b/CMakeLists.txt index 0472fd8dc..a7f342579 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -1480,6 +1480,8 @@ elseif(EMSCRIPTEN) # project. Uncomment at will for verbose cross-compiling -I/../ path info. sdl_compile_options(PRIVATE "-Wno-warn-absolute-paths") + sdl_glob_sources("${SDL3_SOURCE_DIR}/src/core/emscripten/*.c") + sdl_glob_sources("${SDL3_SOURCE_DIR}/src/main/emscripten/*.c") set(HAVE_SDL_MAIN_CALLBACKS TRUE) diff --git a/include/SDL3/SDL_main.h b/include/SDL3/SDL_main.h index e293cc505..cd6a0b332 100644 --- a/include/SDL3/SDL_main.h +++ b/include/SDL3/SDL_main.h @@ -94,6 +94,16 @@ /* We need to export SDL_main so it can be launched from Java */ #define SDLMAIN_DECLSPEC SDL_DECLSPEC + #elif defined(SDL_PLATFORM_EMSCRIPTEN) + /* On Emscripten, SDL provides a main function that converts URL + parameters that start with "SDL_" to environment variables, so + they can be used as SDL hints, etc. + + This is 100% optional, so if you don't want this to happen, you may + define SDL_MAIN_HANDLED + */ + #define SDL_MAIN_AVAILABLE + #elif defined(SDL_PLATFORM_PSP) /* On PSP SDL provides a main function that sets the module info, activates the GPU and starts the thread required to be able to exit diff --git a/src/core/emscripten/SDL_emscripten.c b/src/core/emscripten/SDL_emscripten.c new file mode 100644 index 000000000..6eda16096 --- /dev/null +++ b/src/core/emscripten/SDL_emscripten.c @@ -0,0 +1,56 @@ +/* + Simple DirectMedia Layer + Copyright (C) 1997-2024 Sam Lantinga + + This software is provided 'as-is', without any express or implied + warranty. In no event will the authors be held liable for any damages + arising from the use of this software. + + Permission is granted to anyone to use this software for any purpose, + including commercial applications, and to alter it and redistribute it + freely, subject to the following restrictions: + + 1. The origin of this software must not be misrepresented; you must not + claim that you wrote the original software. If you use this software + in a product, an acknowledgment in the product documentation would be + appreciated but is not required. + 2. Altered source versions must be plainly marked as such, and must not be + misrepresented as being the original software. + 3. This notice may not be removed or altered from any source distribution. +*/ +#include "SDL_internal.h" + +#ifdef SDL_PLATFORM_EMSCRIPTEN + +#include + +EM_JS_DEPS(sdlrunapp, "$dynCall,$stringToNewUTF8"); + +int SDL_RunApp(int argc, char* argv[], SDL_main_func mainFunction, void * reserved) +{ + (void)reserved; + + // Move any URL params that start with "SDL_" over to environment + // variables, so the hint system can pick them up, etc, much like a user + // can set them from a shell prompt on a desktop machine. Ignore all + // other params, in case the app wants to use them for something. + MAIN_THREAD_EM_ASM({ + var parms = new URLSearchParams(window.location.search); + for (const [key, value] of parms) { + if (key.startsWith("SDL_")) { + var ckey = stringToNewUTF8(key); + var cvalue = stringToNewUTF8(value); + if ((ckey != 0) && (cvalue != 0)) { + //console.log("Setting SDL env var '" + key + "' to '" + value + "' ..."); + dynCall('iiii', $0, [ckey, cvalue, 1]); + } + _free(ckey); // these must use free(), not SDL_free()! + _free(cvalue); + } + } + }, SDL_setenv); + + return mainFunction(argc, argv); +} + +#endif