src/ui/gfx/ozone/dri/dri_surface.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ui/gfx/ozone/dri/dri_surface.h"
   6
   7 #include <errno.h>
   8 #include <sys/mman.h>
   9 #include <sys/types.h>
  10 #include <xf86drm.h>
  11
  12 #include "base/logging.h"
  13 #include "third_party/skia/include/core/SkBitmap.h"
  14 #include "third_party/skia/include/core/SkBitmapDevice.h"
  15 #include "third_party/skia/include/core/SkCanvas.h"
  16 #include "ui/gfx/ozone/dri/dri_skbitmap.h"
  17 #include "ui/gfx/ozone/dri/dri_wrapper.h"
  18 #include "ui/gfx/skia_util.h"
  19
  20 namespace gfx {
  21
  22 namespace {
  23
  24 // Extends the SkBitmapDevice to allow setting the SkPixelRef. We use the setter
  25 // to change the SkPixelRef such that the device always points to the
  26 // backbuffer.
  27 class CustomSkBitmapDevice : public SkBitmapDevice {
  28  public:
  29   CustomSkBitmapDevice(const SkBitmap& bitmap) : SkBitmapDevice(bitmap) {}
  30   virtual ~CustomSkBitmapDevice() {}
  31
  32   void SetPixelRef(SkPixelRef* pixel_ref) { setPixelRef(pixel_ref); }
  33
  34  private:
  35   DISALLOW_COPY_AND_ASSIGN(CustomSkBitmapDevice);
  36 };
  37
  38 }  // namespace
  39
  40 ////////////////////////////////////////////////////////////////////////////////
  41 // DriSurface implementation
  42
  43 DriSurface::DriSurface(
  44     DriWrapper* dri, const gfx::Size& size)
  45     : dri_(dri),
  46       bitmaps_(),
  47       front_buffer_(0),
  48       size_(size) {
  49 }
  50
  51 DriSurface::~DriSurface() {
  52 }
  53
  54 bool DriSurface::Initialize() {
  55   for (int i = 0; i < 2; ++i) {
  56     bitmaps_[i].reset(CreateBuffer());
  57     // TODO(dnicoara) Should select the configuration based on what the
  58     // underlying system supports.
  59     SkImageInfo info = SkImageInfo::Make(size_.width(),
  60                                          size_.height(),
  61                                          kPMColor_SkColorType,
  62                                          kPremul_SkAlphaType);
  63     if (!bitmaps_[i]->Initialize(info)) {
  64       return false;
  65     }
  66   }
  67
  68   skia_device_ = skia::AdoptRef(
  69       new CustomSkBitmapDevice(*bitmaps_[front_buffer_ ^ 1].get()));
  70   skia_canvas_ = skia::AdoptRef(new SkCanvas(skia_device_.get()));
  71
  72   return true;
  73 }
  74
  75 uint32_t DriSurface::GetFramebufferId() const {
  76   CHECK(bitmaps_[0].get() && bitmaps_[1].get());
  77   return bitmaps_[front_buffer_ ^ 1]->get_framebuffer();
  78 }
  79
  80 uint32_t DriSurface::GetHandle() const {
  81   CHECK(bitmaps_[0].get() && bitmaps_[1].get());
  82   return bitmaps_[front_buffer_ ^ 1]->get_handle();
  83 }
  84
  85 // This call is made after the hardware just started displaying our back buffer.
  86 // We need to update our pointer reference and synchronize the two buffers.
  87 void DriSurface::SwapBuffers() {
  88   CHECK(bitmaps_[0].get() && bitmaps_[1].get());
  89
  90   // Update our front buffer pointer.
  91   front_buffer_ ^= 1;
  92
  93   // Unlocking will unset the pixel pointer, so it won't be pointing to the old
  94   // PixelRef.
  95   skia_device_->accessBitmap(false).unlockPixels();
  96   // Update the backing pixels for the bitmap device.
  97   static_cast<CustomSkBitmapDevice*>(skia_device_.get())->SetPixelRef(
  98       bitmaps_[front_buffer_ ^ 1]->pixelRef());
  99   // Locking the pixels will set the pixel pointer based on the PixelRef value.
 100   skia_device_->accessBitmap(false).lockPixels();
 101
 102   SkIRect device_damage;
 103   skia_canvas_->getClipDeviceBounds(&device_damage);
 104   SkRect damage = SkRect::Make(device_damage);
 105
 106   skia_canvas_->drawBitmapRectToRect(*bitmaps_[front_buffer_].get(),
 107                                      &damage,
 108                                      damage);
 109 }
 110
 111 SkCanvas* DriSurface::GetDrawableForWidget() {
 112   return skia_canvas_.get();
 113 }
 114
 115 DriSkBitmap* DriSurface::CreateBuffer() {
 116   return new DriSkBitmap(dri_->get_fd());
 117 }
 118
 119 }  // namespace gfx