Function createContext

gpu.hpp:774–865

* @brief Factory function to create a GPU context, which aggregates WebGPU API * handles to interact with the GPU including the instance, adapter, device, and * queue. * * The function takes optional descriptor parameters for the instance * descriptor, adapter request options, and device descriptor, which are passed * through to the WebGPU API calls to create the instance, adapter, and devic

 * @endcode
 */
inline Context createContext(const WGPUInstanceDescriptor &desc = {},
                             const WGPURequestAdapterOptions &adapterOpts = {},
                             const WGPUDeviceDescriptor &devDescriptor = {}) {
  Context context;
  {
#ifdef __EMSCRIPTEN__
    // Emscripten does not support the instance descriptor
    // and throws an assertion error if it is not nullptr.
    context.instance = wgpuCreateInstance(nullptr);
#else
    context.instance = wgpuCreateInstance(&desc);
#endif
    check(context.instance, "Initialize WebGPU", __FILE__, __LINE__);
  }

  LOG(kDefLog, kInfo, "Requesting adapter");
  {
    struct AdapterData {
      WGPUAdapter adapter = nullptr;
      bool requestEnded = false;
    };
    AdapterData adapterData;
    auto onAdapterRequestEnded = [](WGPURequestAdapterStatus status,
                                    WGPUAdapter adapter, char const *message,
                                    void *pUserData) {
      AdapterData &adapterData = *reinterpret_cast<AdapterData *>(pUserData);
#ifdef __EMSCRIPTEN__
      if (status != WGPURequestAdapterStatus_Success) {
        LOG(kDefLog, kError, "Could not get WebGPU adapter: %s", message);
        LOG(kDefLog, kError,
            "\n\nA common reason is that the browser does not have WebGPU "
            "enabled, particularly on Linux.\n"
            "- Open `chrome://flags/` in the browser and make sure "
            "\"WebGPU Support\" is enabled.\n"
            "- Chrome is launched with vulkan enabled. From the command line "
            "launch chrome as `google-chrome --enable-features=Vulkan`\n");
      }
#endif
      check(status == WGPURequestAdapterStatus_Success,
            "Request WebGPU adapter", __FILE__, __LINE__);
      adapterData.adapter = adapter;
      adapterData.requestEnded = true;
    };

    wgpuInstanceRequestAdapter(context.instance, &adapterOpts,
                               onAdapterRequestEnded, (void *)&adapterData);

    while (!adapterData.requestEnded) {
      processEvents(context.instance);
    }
    assert(adapterData.requestEnded);
    context.adapter = adapterData.adapter;
  }

  LOG(kDefLog, kInfo, "Requesting device");
  {
    struct DeviceData {
      WGPUDevice device = nullptr;