diff --git a/src/video/emscripten/SDL_emscriptenframebuffer.c b/src/video/emscripten/SDL_emscriptenframebuffer.c index f252538e4a..3ffbf0df49 100644 --- a/src/video/emscripten/SDL_emscriptenframebuffer.c +++ b/src/video/emscripten/SDL_emscriptenframebuffer.c @@ -67,7 +67,7 @@ bool Emscripten_UpdateWindowFramebuffer(SDL_VideoDevice *_this, SDL_Window *wind // Send the data to the display /* *INDENT-OFF* */ // clang-format off - MAIN_THREAD_EM_ASM({ + int updated = MAIN_THREAD_EM_ASM_INT({ var w = $0; var h = $1; var pixels = $2; @@ -79,6 +79,9 @@ bool Emscripten_UpdateWindowFramebuffer(SDL_VideoDevice *_this, SDL_Window *wind var SDL3 = Module['SDL3']; if (SDL3.ctxCanvas !== canvas) { SDL3.ctx = Browser.createContext(canvas, false, true); + if (!SDL3.ctx) { + return false; + } SDL3.ctxCanvas = canvas; } if (SDL3.w !== w || SDL3.h !== h || SDL3.imageCtx !== SDL3.ctx) { @@ -98,9 +101,14 @@ bool Emscripten_UpdateWindowFramebuffer(SDL_VideoDevice *_this, SDL_Window *wind data32.set(HEAP32.subarray(src, src + data32.length)); SDL3.ctx.putImageData(SDL3.image, 0, 0); + return true; }, surface->w, surface->h, surface->pixels, data->canvas_id); /* *INDENT-ON* */ // clang-format on + if (!updated) { + return SDL_SetError("Couldn't create context for canvas update"); + } + if (emscripten_has_asyncify() && SDL_GetHintBoolean(SDL_HINT_EMSCRIPTEN_ASYNCIFY, true)) { // give back control to browser for screen refresh emscripten_sleep(0);