1 files changed, 459 insertions, 0 deletions

diff --git a/contrib/SDL-3.2.8/src/video/emscripten/SDL_emscriptenvideo.c b/contrib/SDL-3.2.8/src/video/emscripten/SDL_emscriptenvideo.c
new file mode 100644
index 0000000..1496268
--- /dev/null
+++ b/contrib/SDL-3.2.8/src/video/emscripten/SDL_emscriptenvideo.c
@@ -0,0 +1,459 @@
+/*
+  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 "../SDL_sysvideo.h"
+#include "../SDL_pixels_c.h"
+#include "../../events/SDL_events_c.h"
+
+#include "SDL_emscriptenvideo.h"
+#include "SDL_emscriptenopengles.h"
+#include "SDL_emscriptenframebuffer.h"
+#include "SDL_emscriptenevents.h"
+#include "SDL_emscriptenmouse.h"
+
+#define EMSCRIPTENVID_DRIVER_NAME "emscripten"
+
+// Initialization/Query functions
+static bool Emscripten_VideoInit(SDL_VideoDevice *_this);
+static bool Emscripten_SetDisplayMode(SDL_VideoDevice *_this, SDL_VideoDisplay *display, SDL_DisplayMode *mode);
+static void Emscripten_VideoQuit(SDL_VideoDevice *_this);
+static bool Emscripten_GetDisplayUsableBounds(SDL_VideoDevice *_this, SDL_VideoDisplay *display, SDL_Rect *rect);
+
+static bool Emscripten_CreateWindow(SDL_VideoDevice *_this, SDL_Window *window, SDL_PropertiesID create_props);
+static void Emscripten_SetWindowSize(SDL_VideoDevice *_this, SDL_Window *window);
+static void Emscripten_GetWindowSizeInPixels(SDL_VideoDevice *_this, SDL_Window *window, int *w, int *h);
+static void Emscripten_DestroyWindow(SDL_VideoDevice *_this, SDL_Window *window);
+static SDL_FullscreenResult Emscripten_SetWindowFullscreen(SDL_VideoDevice *_this, SDL_Window *window, SDL_VideoDisplay *display, SDL_FullscreenOp fullscreen);
+static void Emscripten_PumpEvents(SDL_VideoDevice *_this);
+static void Emscripten_SetWindowTitle(SDL_VideoDevice *_this, SDL_Window *window);
+
+static bool pumpevents_has_run = false;
+static int pending_swap_interval = -1;
+
+
+// Emscripten driver bootstrap functions
+
+static void Emscripten_DeleteDevice(SDL_VideoDevice *device)
+{
+    SDL_free(device);
+}
+
+static SDL_SystemTheme Emscripten_GetSystemTheme(void)
+{
+    /* Technically, light theme can mean explicit light theme or no preference.
+       https://developer.mozilla.org/en-US/docs/Web/CSS/@media/prefers-color-scheme#syntax */
+
+    int theme_code = EM_ASM_INT({
+        if (!window.matchMedia) {
+            return -1;
+        }
+
+        if (window.matchMedia('(prefers-color-scheme: light)').matches) {
+            return 0;
+        }
+
+        if (window.matchMedia('(prefers-color-scheme: dark)').matches) {
+            return 1;
+        }
+
+        return -1;
+    });
+
+    switch (theme_code) {
+    case 0:
+        return SDL_SYSTEM_THEME_LIGHT;
+
+    case 1:
+        return SDL_SYSTEM_THEME_DARK;
+
+    default:
+        return SDL_SYSTEM_THEME_UNKNOWN;
+    }
+}
+
+static void Emscripten_ListenSystemTheme(void)
+{
+    MAIN_THREAD_EM_ASM({
+        if (window.matchMedia) {
+            if (typeof(Module['SDL3']) === 'undefined') {
+                Module['SDL3'] = {};
+            }
+
+            var SDL3 = Module['SDL3'];
+
+            SDL3.eventHandlerThemeChanged = function(event) {
+                _Emscripten_SendSystemThemeChangedEvent();
+            };
+
+            SDL3.themeChangedMatchMedia = window.matchMedia('(prefers-color-scheme: dark)');
+            SDL3.themeChangedMatchMedia.addEventListener('change', SDL3.eventHandlerThemeChanged);
+        }
+    });
+}
+
+static void Emscripten_UnlistenSystemTheme(void)
+{
+    MAIN_THREAD_EM_ASM({
+        if (typeof(Module['SDL3']) !== 'undefined') {
+            var SDL3 = Module['SDL3'];
+
+            SDL3.themeChangedMatchMedia.removeEventListener('change', SDL3.eventHandlerThemeChanged);
+            SDL3.themeChangedMatchMedia = undefined;
+            SDL3.eventHandlerThemeChanged = undefined;
+        }
+    });
+}
+
+EMSCRIPTEN_KEEPALIVE void Emscripten_SendSystemThemeChangedEvent(void)
+{
+    SDL_SetSystemTheme(Emscripten_GetSystemTheme());
+}
+
+static SDL_VideoDevice *Emscripten_CreateDevice(void)
+{
+    SDL_VideoDevice *device;
+
+    // Initialize all variables that we clean on shutdown
+    device = (SDL_VideoDevice *)SDL_calloc(1, sizeof(SDL_VideoDevice));
+    if (!device) {
+        return NULL;
+    }
+
+    /* Firefox sends blur event which would otherwise prevent full screen
+     * when the user clicks to allow full screen.
+     * See https://bugzilla.mozilla.org/show_bug.cgi?id=1144964
+     */
+    SDL_SetHint(SDL_HINT_VIDEO_MINIMIZE_ON_FOCUS_LOSS, "0");
+
+    // Set the function pointers
+    device->VideoInit = Emscripten_VideoInit;
+    device->VideoQuit = Emscripten_VideoQuit;
+    device->GetDisplayUsableBounds = Emscripten_GetDisplayUsableBounds;
+    device->SetDisplayMode = Emscripten_SetDisplayMode;
+
+    device->PumpEvents = Emscripten_PumpEvents;
+
+    device->CreateSDLWindow = Emscripten_CreateWindow;
+    device->SetWindowTitle = Emscripten_SetWindowTitle;
+    /*device->SetWindowIcon = Emscripten_SetWindowIcon;
+    device->SetWindowPosition = Emscripten_SetWindowPosition;*/
+    device->SetWindowSize = Emscripten_SetWindowSize;
+    /*device->ShowWindow = Emscripten_ShowWindow;
+    device->HideWindow = Emscripten_HideWindow;
+    device->RaiseWindow = Emscripten_RaiseWindow;
+    device->MaximizeWindow = Emscripten_MaximizeWindow;
+    device->MinimizeWindow = Emscripten_MinimizeWindow;
+    device->RestoreWindow = Emscripten_RestoreWindow;
+    device->SetWindowMouseGrab = Emscripten_SetWindowMouseGrab;*/
+    device->GetWindowSizeInPixels = Emscripten_GetWindowSizeInPixels;
+    device->DestroyWindow = Emscripten_DestroyWindow;
+    device->SetWindowFullscreen = Emscripten_SetWindowFullscreen;
+
+    device->CreateWindowFramebuffer = Emscripten_CreateWindowFramebuffer;
+    device->UpdateWindowFramebuffer = Emscripten_UpdateWindowFramebuffer;
+    device->DestroyWindowFramebuffer = Emscripten_DestroyWindowFramebuffer;
+
+    device->GL_LoadLibrary = Emscripten_GLES_LoadLibrary;
+    device->GL_GetProcAddress = Emscripten_GLES_GetProcAddress;
+    device->GL_UnloadLibrary = Emscripten_GLES_UnloadLibrary;
+    device->GL_CreateContext = Emscripten_GLES_CreateContext;
+    device->GL_MakeCurrent = Emscripten_GLES_MakeCurrent;
+    device->GL_SetSwapInterval = Emscripten_GLES_SetSwapInterval;
+    device->GL_GetSwapInterval = Emscripten_GLES_GetSwapInterval;
+    device->GL_SwapWindow = Emscripten_GLES_SwapWindow;
+    device->GL_DestroyContext = Emscripten_GLES_DestroyContext;
+
+    device->free = Emscripten_DeleteDevice;
+
+    Emscripten_ListenSystemTheme();
+    device->system_theme = Emscripten_GetSystemTheme();
+
+    return device;
+}
+
+VideoBootStrap Emscripten_bootstrap = {
+    EMSCRIPTENVID_DRIVER_NAME, "SDL emscripten video driver",
+    Emscripten_CreateDevice,
+    NULL, // no ShowMessageBox implementation
+    false
+};
+
+bool Emscripten_VideoInit(SDL_VideoDevice *_this)
+{
+    SDL_DisplayMode mode;
+
+    // Use a fake 32-bpp desktop mode
+    SDL_zero(mode);
+    mode.format = SDL_PIXELFORMAT_XRGB8888;
+    emscripten_get_screen_size(&mode.w, &mode.h);
+    mode.pixel_density = emscripten_get_device_pixel_ratio();
+
+    if (SDL_AddBasicVideoDisplay(&mode) == 0) {
+        return false;
+    }
+
+    Emscripten_InitMouse();
+
+    // Assume we have a mouse and keyboard
+    SDL_AddKeyboard(SDL_DEFAULT_KEYBOARD_ID, NULL, false);
+    SDL_AddMouse(SDL_DEFAULT_MOUSE_ID, NULL, false);
+
+    // We're done!
+    return true;
+}
+
+static bool Emscripten_SetDisplayMode(SDL_VideoDevice *_this, SDL_VideoDisplay *display, SDL_DisplayMode *mode)
+{
+    // can't do this
+    return true;
+}
+
+static void Emscripten_VideoQuit(SDL_VideoDevice *_this)
+{
+    Emscripten_QuitMouse();
+    Emscripten_UnlistenSystemTheme();
+    pumpevents_has_run = false;
+    pending_swap_interval = -1;
+}
+
+static bool Emscripten_GetDisplayUsableBounds(SDL_VideoDevice *_this, SDL_VideoDisplay *display, SDL_Rect *rect)
+{
+    if (rect) {
+        rect->x = 0;
+        rect->y = 0;
+        rect->w = MAIN_THREAD_EM_ASM_INT({
+            return window.innerWidth;
+        });
+        rect->h = MAIN_THREAD_EM_ASM_INT({
+            return window.innerHeight;
+        });
+    }
+    return true;
+}
+
+bool Emscripten_ShouldSetSwapInterval(int interval)
+{
+    if (!pumpevents_has_run) {
+        pending_swap_interval = interval;
+        return false;
+    }
+    return true;
+}
+
+static void Emscripten_PumpEvents(SDL_VideoDevice *_this)
+{
+    if (!pumpevents_has_run) {
+        // we assume you've set a mainloop by the time you've called pumpevents, so we delay initial SetInterval changes until then.
+        // otherwise you'll get a warning on the javascript console.
+        pumpevents_has_run = true;
+        if (pending_swap_interval >= 0) {
+            Emscripten_GLES_SetSwapInterval(_this, pending_swap_interval);
+            pending_swap_interval = -1;
+        }
+    }
+}
+
+EMSCRIPTEN_KEEPALIVE void requestFullscreenThroughSDL(SDL_Window *window)
+{
+    SDL_SetWindowFullscreen(window, true);
+}
+
+static bool Emscripten_CreateWindow(SDL_VideoDevice *_this, SDL_Window *window, SDL_PropertiesID props)
+{
+    SDL_WindowData *wdata;
+    double scaled_w, scaled_h;
+    double css_w, css_h;
+    const char *selector;
+
+    // Allocate window internal data
+    wdata = (SDL_WindowData *)SDL_calloc(1, sizeof(SDL_WindowData));
+    if (!wdata) {
+        return false;
+    }
+
+    selector = SDL_GetHint(SDL_HINT_EMSCRIPTEN_CANVAS_SELECTOR);
+    if (!selector) {
+        selector = "#canvas";
+    }
+
+    wdata->canvas_id = SDL_strdup(selector);
+
+    if (window->flags & SDL_WINDOW_HIGH_PIXEL_DENSITY) {
+        wdata->pixel_ratio = emscripten_get_device_pixel_ratio();
+    } else {
+        wdata->pixel_ratio = 1.0f;
+    }
+
+    scaled_w = SDL_floor(window->w * wdata->pixel_ratio);
+    scaled_h = SDL_floor(window->h * wdata->pixel_ratio);
+
+    // set a fake size to check if there is any CSS sizing the canvas
+    emscripten_set_canvas_element_size(wdata->canvas_id, 1, 1);
+    emscripten_get_element_css_size(wdata->canvas_id, &css_w, &css_h);
+
+    wdata->external_size = SDL_floor(css_w) != 1 || SDL_floor(css_h) != 1;
+
+    if ((window->flags & SDL_WINDOW_RESIZABLE) && wdata->external_size) {
+        // external css has resized us
+        scaled_w = css_w * wdata->pixel_ratio;
+        scaled_h = css_h * wdata->pixel_ratio;
+
+        SDL_SendWindowEvent(window, SDL_EVENT_WINDOW_RESIZED, SDL_lroundf(css_w), SDL_lroundf(css_h));
+    }
+    emscripten_set_canvas_element_size(wdata->canvas_id, SDL_lroundf(scaled_w), SDL_lroundf(scaled_h));
+
+    // if the size is not being controlled by css, we need to scale down for hidpi
+    if (!wdata->external_size) {
+        if (wdata->pixel_ratio != 1.0f) {
+            // scale canvas down
+            emscripten_set_element_css_size(wdata->canvas_id, window->w, window->h);
+        }
+    }
+
+    wdata->window = window;
+
+    // Setup driver data for this window
+    window->internal = wdata;
+
+    // One window, it always has focus
+    SDL_SetMouseFocus(window);
+    SDL_SetKeyboardFocus(window);
+
+    Emscripten_RegisterEventHandlers(wdata);
+
+    // disable the emscripten "fullscreen" button.
+    MAIN_THREAD_EM_ASM({
+        Module['requestFullscreen'] = function(lockPointer, resizeCanvas) {
+            _requestFullscreenThroughSDL($0);
+        };
+    }, window);
+
+    // Window has been successfully created
+    return true;
+}
+
+static void Emscripten_SetWindowSize(SDL_VideoDevice *_this, SDL_Window *window)
+{
+    SDL_WindowData *data;
+
+    if (window->internal) {
+        data = window->internal;
+        // update pixel ratio
+        if (window->flags & SDL_WINDOW_HIGH_PIXEL_DENSITY) {
+            data->pixel_ratio = emscripten_get_device_pixel_ratio();
+        }
+        emscripten_set_canvas_element_size(data->canvas_id, SDL_lroundf(window->pending.w * data->pixel_ratio), SDL_lroundf(window->pending.h * data->pixel_ratio));
+
+        // scale canvas down
+        if (!data->external_size && data->pixel_ratio != 1.0f) {
+            emscripten_set_element_css_size(data->canvas_id, window->pending.w, window->pending.h);
+        }
+
+        SDL_SendWindowEvent(window, SDL_EVENT_WINDOW_RESIZED, window->pending.w, window->pending.h);
+    }
+}
+
+static void Emscripten_GetWindowSizeInPixels(SDL_VideoDevice *_this, SDL_Window *window, int *w, int *h)
+{
+    SDL_WindowData *data;
+    if (window->internal) {
+        data = window->internal;
+        *w = SDL_lroundf(window->w * data->pixel_ratio);
+        *h = SDL_lroundf(window->h * data->pixel_ratio);
+    }
+}
+
+static void Emscripten_DestroyWindow(SDL_VideoDevice *_this, SDL_Window *window)
+{
+    SDL_WindowData *data;
+
+    if (window->internal) {
+        data = window->internal;
+
+        Emscripten_UnregisterEventHandlers(data);
+
+        // We can't destroy the canvas, so resize it to zero instead
+        emscripten_set_canvas_element_size(data->canvas_id, 0, 0);
+        SDL_free(data->canvas_id);
+
+        SDL_free(window->internal);
+        window->internal = NULL;
+    }
+
+    // just ignore clicks on the fullscreen button while there's no SDL window.
+    MAIN_THREAD_EM_ASM({ Module['requestFullscreen'] = function(lockPointer, resizeCanvas) {}; });
+}
+
+static SDL_FullscreenResult Emscripten_SetWindowFullscreen(SDL_VideoDevice *_this, SDL_Window *window, SDL_VideoDisplay *display, SDL_FullscreenOp fullscreen)
+{
+    SDL_WindowData *data;
+    int res = -1;
+
+    if (window->internal) {
+        data = window->internal;
+
+        if (fullscreen) {
+            EmscriptenFullscreenStrategy strategy;
+            bool is_fullscreen_desktop = !window->fullscreen_exclusive;
+
+            SDL_zero(strategy);
+            strategy.scaleMode = is_fullscreen_desktop ? EMSCRIPTEN_FULLSCREEN_SCALE_STRETCH : EMSCRIPTEN_FULLSCREEN_SCALE_ASPECT;
+
+            if (!is_fullscreen_desktop) {
+                strategy.canvasResolutionScaleMode = EMSCRIPTEN_FULLSCREEN_CANVAS_SCALE_NONE;
+            } else if (window->flags & SDL_WINDOW_HIGH_PIXEL_DENSITY) {
+                strategy.canvasResolutionScaleMode = EMSCRIPTEN_FULLSCREEN_CANVAS_SCALE_HIDEF;
+            } else {
+                strategy.canvasResolutionScaleMode = EMSCRIPTEN_FULLSCREEN_CANVAS_SCALE_STDDEF;
+            }
+
+            strategy.filteringMode = EMSCRIPTEN_FULLSCREEN_FILTERING_DEFAULT;
+
+            strategy.canvasResizedCallback = Emscripten_HandleCanvasResize;
+            strategy.canvasResizedCallbackUserData = data;
+
+            data->fullscreen_mode_flags = (window->flags & SDL_WINDOW_FULLSCREEN);
+            data->fullscreen_resize = is_fullscreen_desktop;
+
+            res = emscripten_request_fullscreen_strategy(data->canvas_id, 1, &strategy);
+        } else {
+            res = emscripten_exit_fullscreen();
+        }
+    }
+
+    if (res == EMSCRIPTEN_RESULT_SUCCESS) {
+        return SDL_FULLSCREEN_SUCCEEDED;
+    } else if (res == EMSCRIPTEN_RESULT_DEFERRED) {
+        return SDL_FULLSCREEN_PENDING;
+    } else {
+        return SDL_FULLSCREEN_FAILED;
+    }
+}
+
+static void Emscripten_SetWindowTitle(SDL_VideoDevice *_this, SDL_Window *window)
+{
+    emscripten_set_window_title(window->title);
+}
+
+#endif // SDL_VIDEO_DRIVER_EMSCRIPTEN