// Copyright 2018 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

module viz.mojom;

import "ui/gfx/geometry/mojo/geometry.mojom";

// The syscalls needed to update a layered window are blocked by the GPU
// sandbox. This interface lets the GPU draw into shared memory and then send
// an IPC to the browser to call UpdateLayeredWindow().
interface LayeredWindowUpdater {
  // A new shared memory buffer has been allocated for |pixel_size|. The shared
  // memory buffer must be at least big enough to contain |pixel_size| in
  // RGBA_8888. The shared memory buffer will be used with subsequent calls to
  // Draw().
  OnAllocatedSharedMemory(
    gfx.mojom.Size pixel_size,
    handle<shared_buffer> scoped_buffer_handle
  );

  // Draws to the HWND by copying pixels from shared memory. Callback must be
  // called after draw operation is complete to signal shared memory can be
  // modified.
  Draw() => ();
};