1 files changed, 162 insertions, 0 deletions

diff --git a/contrib/SDL-3.2.8/src/video/emscripten/SDL_emscriptenopengles.c b/contrib/SDL-3.2.8/src/video/emscripten/SDL_emscriptenopengles.c
new file mode 100644
index 0000000..227cdc5
--- /dev/null
+++ b/contrib/SDL-3.2.8/src/video/emscripten/SDL_emscriptenopengles.c
@@ -0,0 +1,162 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+
+  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_VIDEO_DRIVER_EMSCRIPTEN
+
+#include <emscripten/emscripten.h>
+#include <emscripten/html5_webgl.h>
+#include <GLES2/gl2.h>
+
+#include "SDL_emscriptenvideo.h"
+#include "SDL_emscriptenopengles.h"
+
+bool Emscripten_GLES_LoadLibrary(SDL_VideoDevice *_this, const char *path)
+{
+    return true;
+}
+
+void Emscripten_GLES_UnloadLibrary(SDL_VideoDevice *_this)
+{
+}
+
+SDL_FunctionPointer Emscripten_GLES_GetProcAddress(SDL_VideoDevice *_this, const char *proc)
+{
+    return emscripten_webgl_get_proc_address(proc);
+}
+
+bool Emscripten_GLES_SetSwapInterval(SDL_VideoDevice *_this, int interval)
+{
+    if (interval < 0) {
+        return SDL_SetError("Late swap tearing currently unsupported");
+    }
+
+    if (Emscripten_ShouldSetSwapInterval(interval)) {
+        if (interval == 0) {
+            emscripten_set_main_loop_timing(EM_TIMING_SETTIMEOUT, 0);
+        } else {
+            emscripten_set_main_loop_timing(EM_TIMING_RAF, interval);
+        }
+    }
+
+    return true;
+}
+
+bool Emscripten_GLES_GetSwapInterval(SDL_VideoDevice *_this, int *interval)
+{
+    int mode, value;
+
+    emscripten_get_main_loop_timing(&mode, &value);
+
+    if (mode == EM_TIMING_RAF) {
+        *interval = value;
+        return true;
+    } else {
+        *interval = 0;
+        return true;
+    }
+}
+
+SDL_GLContext Emscripten_GLES_CreateContext(SDL_VideoDevice *_this, SDL_Window *window)
+{
+    SDL_WindowData *window_data;
+
+    EmscriptenWebGLContextAttributes attribs;
+    EMSCRIPTEN_WEBGL_CONTEXT_HANDLE context;
+
+    emscripten_webgl_init_context_attributes(&attribs);
+
+    attribs.alpha = _this->gl_config.alpha_size > 0;
+    attribs.depth = _this->gl_config.depth_size > 0;
+    attribs.stencil = _this->gl_config.stencil_size > 0;
+    attribs.antialias = _this->gl_config.multisamplebuffers == 1;
+
+    if (_this->gl_config.major_version == 3)
+        attribs.majorVersion = 2; // WebGL 2.0 ~= GLES 3.0
+
+    window_data = window->internal;
+
+    if (window_data->gl_context) {
+        SDL_SetError("Cannot create multiple webgl contexts per window");
+        return NULL;
+    }
+
+    context = emscripten_webgl_create_context(window_data->canvas_id, &attribs);
+
+    if (context < 0) {
+        SDL_SetError("Could not create webgl context");
+        return NULL;
+    }
+
+    if (emscripten_webgl_make_context_current(context) != EMSCRIPTEN_RESULT_SUCCESS) {
+        emscripten_webgl_destroy_context(context);
+        return NULL;
+    }
+
+    window_data->gl_context = (SDL_GLContext)context;
+
+    return (SDL_GLContext)context;
+}
+
+bool Emscripten_GLES_DestroyContext(SDL_VideoDevice *_this, SDL_GLContext context)
+{
+    SDL_Window *window;
+
+    // remove the context from its window
+    for (window = _this->windows; window; window = window->next) {
+        SDL_WindowData *window_data = window->internal;
+
+        if (window_data->gl_context == context) {
+            window_data->gl_context = NULL;
+        }
+    }
+
+    emscripten_webgl_destroy_context((EMSCRIPTEN_WEBGL_CONTEXT_HANDLE)context);
+    return true;
+}
+
+bool Emscripten_GLES_SwapWindow(SDL_VideoDevice *_this, SDL_Window *window)
+{
+    if (emscripten_has_asyncify() && SDL_GetHintBoolean(SDL_HINT_EMSCRIPTEN_ASYNCIFY, true)) {
+        // give back control to browser for screen refresh
+        emscripten_sleep(0);
+    }
+    return true;
+}
+
+bool Emscripten_GLES_MakeCurrent(SDL_VideoDevice *_this, SDL_Window *window, SDL_GLContext context)
+{
+    // it isn't possible to reuse contexts across canvases
+    if (window && context) {
+        SDL_WindowData *window_data = window->internal;
+
+        if (context != window_data->gl_context) {
+            return SDL_SetError("Cannot make context current to another window");
+        }
+    }
+
+    if (emscripten_webgl_make_context_current((EMSCRIPTEN_WEBGL_CONTEXT_HANDLE)context) != EMSCRIPTEN_RESULT_SUCCESS) {
+        return SDL_SetError("Unable to make context current");
+    }
+    return true;
+}
+
+#endif // SDL_VIDEO_DRIVER_EMSCRIPTEN