chromium/ui/ozone/platform/wayland/gpu/wayland_canvas_surface.h

// Copyright 2019 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_OZONE_PLATFORM_WAYLAND_GPU_WAYLAND_CANVAS_SURFACE_H_
#define UI_OZONE_PLATFORM_WAYLAND_GPU_WAYLAND_CANVAS_SURFACE_H_

#include <memory>
#include <vector>

#include "base/memory/raw_ptr.h"
#include "base/memory/weak_ptr.h"
#include "base/time/time.h"
#include "third_party/skia/include/core/SkRefCnt.h"
#include "third_party/skia/include/core/SkSurface.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gfx/native_widget_types.h"
#include "ui/gfx/vsync_provider.h"
#include "ui/ozone/platform/wayland/gpu/wayland_surface_gpu.h"
#include "ui/ozone/public/surface_ozone_canvas.h"

class SkCanvas;

namespace ui {

class WaylandBufferManagerGpu;

// WaylandCanvasSurface creates an SkCanvas whose contents is backed by a shared
// memory region. The shared memory region is registered with the Wayland server
// as a wl_buffer.
//
// Basic control flow:
//   1. WaylandCanvasSurface creates an anonymous shared memory region.
//   2. WaylandCanvasSurface creates an SkCanvas that rasters directly into
//   this shared memory region.
//   3. WaylandCanvasSurface registers the shared memory region with the
//   WaylandServer via IPC through WaylandBufferManagerGpu and
//   WaylandBufferManagerHost. See
//   WaylandBufferManagerHost::CreateShmBasedBuffer. This creates a wl_buffer
//   object in the browser process.
//   4. WaylandCanvasSurface::CommitBuffer simply routes via IPC through the
//   browser process to the Wayland server. It is not safe to modify the shared
//   memory region in (1) until OnSubmission/OnPresentation callbacks are
//   received.
class WaylandCanvasSurface : public SurfaceOzoneCanvas,
                             public WaylandSurfaceGpu { … };

}  // namespace ui

#endif  // UI_OZONE_PLATFORM_WAYLAND_GPU_WAYLAND_CANVAS_SURFACE_H_