1 files changed, 216 insertions, 0 deletions

diff --git a/contrib/SDL-3.2.8/src/video/emscripten/SDL_emscriptenmouse.c b/contrib/SDL-3.2.8/src/video/emscripten/SDL_emscriptenmouse.c
new file mode 100644
index 0000000..c959804
--- /dev/null
+++ b/contrib/SDL-3.2.8/src/video/emscripten/SDL_emscriptenmouse.c
@@ -0,0 +1,216 @@
+/*
+  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.h>
+#include <emscripten/threading.h>
+
+#include "SDL_emscriptenmouse.h"
+#include "SDL_emscriptenvideo.h"
+
+#include "../SDL_video_c.h"
+#include "../../events/SDL_mouse_c.h"
+
+// older Emscriptens don't have this, but we need to for wasm64 compatibility.
+#ifndef MAIN_THREAD_EM_ASM_PTR
+    #ifdef __wasm64__
+        #error You need to upgrade your Emscripten compiler to support wasm64
+    #else
+        #define MAIN_THREAD_EM_ASM_PTR MAIN_THREAD_EM_ASM_INT
+    #endif
+#endif
+
+static SDL_Cursor *Emscripten_CreateCursorFromString(const char *cursor_str, bool is_custom)
+{
+    SDL_CursorData *curdata;
+    SDL_Cursor *cursor = SDL_calloc(1, sizeof(SDL_Cursor));
+    if (cursor) {
+        curdata = (SDL_CursorData *)SDL_calloc(1, sizeof(*curdata));
+        if (!curdata) {
+            SDL_free(cursor);
+            return NULL;
+        }
+
+        curdata->system_cursor = cursor_str;
+        curdata->is_custom = is_custom;
+        cursor->internal = curdata;
+    }
+
+    return cursor;
+}
+
+static SDL_Cursor *Emscripten_CreateDefaultCursor(void)
+{
+    SDL_SystemCursor id = SDL_GetDefaultSystemCursor();
+    const char *cursor_name = SDL_GetCSSCursorName(id, NULL);
+    return Emscripten_CreateCursorFromString(cursor_name, false);
+}
+
+EM_JS_DEPS(sdlmouse, "$stringToUTF8,$UTF8ToString");
+
+static SDL_Cursor *Emscripten_CreateCursor(SDL_Surface *surface, int hot_x, int hot_y)
+{
+    const char *cursor_url = NULL;
+    SDL_Surface *conv_surf;
+
+    conv_surf = SDL_ConvertSurface(surface, SDL_PIXELFORMAT_ABGR8888);
+
+    if (!conv_surf) {
+        return NULL;
+    }
+
+    /* *INDENT-OFF* */ // clang-format off
+    cursor_url = (const char *)MAIN_THREAD_EM_ASM_PTR({
+        var w = $0;
+        var h = $1;
+        var hot_x = $2;
+        var hot_y = $3;
+        var pixels = $4;
+
+        var canvas = document.createElement("canvas");
+        canvas.width = w;
+        canvas.height = h;
+
+        var ctx = canvas.getContext("2d");
+
+        var image = ctx.createImageData(w, h);
+        var data = image.data;
+        var src = pixels / 4;
+
+        var data32 = new Int32Array(data.buffer);
+        data32.set(HEAP32.subarray(src, src + data32.length));
+
+        ctx.putImageData(image, 0, 0);
+        var url = hot_x === 0 && hot_y === 0
+            ? "url(" + canvas.toDataURL() + "), auto"
+            : "url(" + canvas.toDataURL() + ") " + hot_x + " " + hot_y + ", auto";
+
+        var urlBuf = _SDL_malloc(url.length + 1);
+        stringToUTF8(url, urlBuf, url.length + 1);
+
+        return urlBuf;
+    }, surface->w, surface->h, hot_x, hot_y, conv_surf->pixels);
+    /* *INDENT-ON* */ // clang-format on
+
+    SDL_DestroySurface(conv_surf);
+
+    return Emscripten_CreateCursorFromString(cursor_url, true);
+}
+
+static SDL_Cursor *Emscripten_CreateSystemCursor(SDL_SystemCursor id)
+{
+    const char *cursor_name = SDL_GetCSSCursorName(id, NULL);
+
+    return Emscripten_CreateCursorFromString(cursor_name, false);
+}
+
+static void Emscripten_FreeCursor(SDL_Cursor *cursor)
+{
+    SDL_CursorData *curdata;
+    if (cursor) {
+        curdata = cursor->internal;
+
+        if (curdata) {
+            if (curdata->is_custom) {
+                SDL_free((char *)curdata->system_cursor);
+            }
+            SDL_free(cursor->internal);
+        }
+
+        SDL_free(cursor);
+    }
+}
+
+static bool Emscripten_ShowCursor(SDL_Cursor *cursor)
+{
+    SDL_CursorData *curdata;
+    if (SDL_GetMouseFocus() != NULL) {
+        if (cursor && cursor->internal) {
+            curdata = cursor->internal;
+
+            if (curdata->system_cursor) {
+                /* *INDENT-OFF* */ // clang-format off
+                MAIN_THREAD_EM_ASM({
+                    if (Module['canvas']) {
+                        Module['canvas'].style['cursor'] = UTF8ToString($0);
+                    }
+                }, curdata->system_cursor);
+                /* *INDENT-ON* */ // clang-format on
+            }
+        } else {
+            /* *INDENT-OFF* */ // clang-format off
+            MAIN_THREAD_EM_ASM(
+                if (Module['canvas']) {
+                    Module['canvas'].style['cursor'] = 'none';
+                }
+            );
+            /* *INDENT-ON* */ // clang-format on
+        }
+    }
+    return true;
+}
+
+static bool Emscripten_SetRelativeMouseMode(bool enabled)
+{
+    SDL_Window *window;
+    SDL_WindowData *window_data;
+
+    // TODO: pointer lock isn't actually enabled yet
+    if (enabled) {
+        window = SDL_GetMouseFocus();
+        if (!window) {
+            return false;
+        }
+
+        window_data = window->internal;
+
+        if (emscripten_request_pointerlock(window_data->canvas_id, 1) >= EMSCRIPTEN_RESULT_SUCCESS) {
+            return true;
+        }
+    } else {
+        if (emscripten_exit_pointerlock() >= EMSCRIPTEN_RESULT_SUCCESS) {
+            return true;
+        }
+    }
+    return false;
+}
+
+void Emscripten_InitMouse(void)
+{
+    SDL_Mouse *mouse = SDL_GetMouse();
+
+    mouse->CreateCursor = Emscripten_CreateCursor;
+    mouse->ShowCursor = Emscripten_ShowCursor;
+    mouse->FreeCursor = Emscripten_FreeCursor;
+    mouse->CreateSystemCursor = Emscripten_CreateSystemCursor;
+    mouse->SetRelativeMouseMode = Emscripten_SetRelativeMouseMode;
+
+    SDL_SetDefaultCursor(Emscripten_CreateDefaultCursor());
+}
+
+void Emscripten_QuitMouse(void)
+{
+}
+
+#endif // SDL_VIDEO_DRIVER_EMSCRIPTEN