ash/display/root_window_transformers.cc

   1 // Copyright (c) 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 "ash/display/root_window_transformers.h"
   6
   7 #include <cmath>
   8
   9 #include "ash/ash_switches.h"
  10 #include "ash/display/display_info.h"
  11 #include "ash/display/display_manager.h"
  12 #include "ash/host/root_window_transformer.h"
  13 #include "ash/magnifier/magnification_controller.h"
  14 #include "ash/shell.h"
  15 #include "base/basictypes.h"
  16 #include "base/command_line.h"
  17 #include "base/memory/scoped_ptr.h"
  18 #include "third_party/skia/include/utils/SkMatrix44.h"
  19 #include "ui/aura/window_event_dispatcher.h"
  20 #include "ui/aura/window_property.h"
  21 #include "ui/compositor/dip_util.h"
  22 #include "ui/gfx/display.h"
  23 #include "ui/gfx/geometry/insets.h"
  24 #include "ui/gfx/geometry/size_conversions.h"
  25 #include "ui/gfx/transform.h"
  26 #include "ui/gfx/transform.h"
  27
  28 DECLARE_WINDOW_PROPERTY_TYPE(gfx::Display::Rotation);
  29
  30 namespace ash {
  31 namespace {
  32
  33 #if defined(OS_WIN)
  34 DEFINE_WINDOW_PROPERTY_KEY(gfx::Display::Rotation, kRotationPropertyKey,
  35                            gfx::Display::ROTATE_0);
  36 #endif
  37
  38 // Round near zero value to zero.
  39 void RoundNearZero(gfx::Transform* transform) {
  40   const float kEpsilon = 0.001f;
  41   SkMatrix44& matrix = transform->matrix();
  42   for (int x = 0; x < 4; ++x) {
  43     for (int y = 0; y < 4; ++y) {
  44       if (std::abs(SkMScalarToFloat(matrix.get(x, y))) < kEpsilon)
  45         matrix.set(x, y, SkFloatToMScalar(0.0f));
  46     }
  47   }
  48 }
  49
  50 // TODO(oshima): Transformers should be able to adjust itself
  51 // when the device scale factor is changed, instead of
  52 // precalculating the transform using fixed value.
  53
  54 gfx::Transform CreateRotationTransform(aura::Window* root_window,
  55                                        const gfx::Display& display) {
  56   DisplayInfo info =
  57       Shell::GetInstance()->display_manager()->GetDisplayInfo(display.id());
  58
  59   // TODO(oshima): Add animation. (crossfade+rotation, or just cross-fade)
  60 #if defined(OS_WIN)
  61   // Windows 8 bots refused to resize the host window, and
  62   // updating the transform results in incorrectly resizing
  63   // the root window. Don't apply the transform unless
  64   // necessary so that unit tests pass on win8 bots.
  65   if (info.GetActiveRotation() ==
  66       root_window->GetProperty(kRotationPropertyKey)) {
  67     return gfx::Transform();
  68   }
  69   root_window->SetProperty(kRotationPropertyKey, info.GetActiveRotation());
  70 #endif
  71
  72   gfx::Transform rotate;
  73   // The origin is (0, 0), so the translate width/height must be reduced by
  74   // 1 pixel.
  75   float one_pixel = 1.0f / display.device_scale_factor();
  76   switch (info.GetActiveRotation()) {
  77     case gfx::Display::ROTATE_0:
  78       break;
  79     case gfx::Display::ROTATE_90:
  80       rotate.Translate(display.bounds().height() - one_pixel, 0);
  81       rotate.Rotate(90);
  82       break;
  83     case gfx::Display::ROTATE_270:
  84       rotate.Translate(0, display.bounds().width() - one_pixel);
  85       rotate.Rotate(270);
  86       break;
  87     case gfx::Display::ROTATE_180:
  88       rotate.Translate(display.bounds().width() - one_pixel,
  89                        display.bounds().height() - one_pixel);
  90       rotate.Rotate(180);
  91       break;
  92   }
  93
  94   RoundNearZero(&rotate);
  95   return rotate;
  96 }
  97
  98 gfx::Transform CreateMagnifierTransform(aura::Window* root_window) {
  99   MagnificationController* magnifier =
 100       Shell::GetInstance()->magnification_controller();
 101   float magnifier_scale = 1.f;
 102   gfx::Point magnifier_offset;
 103   if (magnifier && magnifier->IsEnabled()) {
 104     magnifier_scale = magnifier->GetScale();
 105     magnifier_offset = magnifier->GetWindowPosition();
 106   }
 107   gfx::Transform transform;
 108   if (magnifier_scale != 1.f) {
 109     transform.Scale(magnifier_scale, magnifier_scale);
 110     transform.Translate(-magnifier_offset.x(), -magnifier_offset.y());
 111   }
 112   return transform;
 113 }
 114
 115 gfx::Transform CreateInsetsAndScaleTransform(const gfx::Insets& insets,
 116                                              float device_scale_factor,
 117                                              float ui_scale) {
 118   gfx::Transform transform;
 119   if (insets.top() != 0 || insets.left() != 0) {
 120     float x_offset = insets.left() / device_scale_factor;
 121     float y_offset = insets.top() / device_scale_factor;
 122     transform.Translate(x_offset, y_offset);
 123   }
 124   float inverted_scale = 1.0f / ui_scale;
 125   transform.Scale(inverted_scale, inverted_scale);
 126   return transform;
 127 }
 128
 129 gfx::Transform CreateMirrorTransform(const gfx::Display& display) {
 130   gfx::Transform transform;
 131   transform.matrix().set3x3(-1, 0, 0,
 132                             0, 1, 0,
 133                             0, 0, 1);
 134   transform.Translate(-display.size().width(), 0);
 135   return transform;
 136 }
 137
 138 // RootWindowTransformer for ash environment.
 139 class AshRootWindowTransformer : public RootWindowTransformer {
 140  public:
 141   AshRootWindowTransformer(aura::Window* root,
 142                            const gfx::Display& display)
 143       : root_window_(root) {
 144     DisplayInfo info = Shell::GetInstance()->display_manager()->
 145         GetDisplayInfo(display.id());
 146     host_insets_ = info.GetOverscanInsetsInPixel();
 147     root_window_ui_scale_ = info.GetEffectiveUIScale();
 148     root_window_bounds_transform_ =
 149         CreateInsetsAndScaleTransform(host_insets_,
 150                                       display.device_scale_factor(),
 151                                       root_window_ui_scale_) *
 152         CreateRotationTransform(root, display);
 153     if (base::CommandLine::ForCurrentProcess()->HasSwitch(
 154             switches::kAshEnableMirroredScreen)) {
 155       // Apply the tranform that flips the screen image horizontally so that
 156       // the screen looks normal when reflected on a mirror.
 157       root_window_bounds_transform_ =
 158           root_window_bounds_transform_ * CreateMirrorTransform(display);
 159     }
 160     transform_ = root_window_bounds_transform_ * CreateMagnifierTransform(root);
 161
 162     CHECK(transform_.GetInverse(&invert_transform_));
 163   }
 164
 165   // aura::RootWindowTransformer overrides:
 166   gfx::Transform GetTransform() const override { return transform_; }
 167   gfx::Transform GetInverseTransform() const override {
 168     return invert_transform_;
 169   }
 170   gfx::Rect GetRootWindowBounds(const gfx::Size& host_size) const override {
 171     gfx::Rect bounds(host_size);
 172     bounds.Inset(host_insets_);
 173     bounds = ui::ConvertRectToDIP(root_window_->layer(), bounds);
 174     gfx::RectF new_bounds(bounds);
 175     root_window_bounds_transform_.TransformRect(&new_bounds);
 176     // Apply |root_window_scale_| twice as the downscaling
 177     // is already applied once in |SetTransformInternal()|.
 178     // TODO(oshima): This is a bit ugly. Consider specifying
 179     // the pseudo host resolution instead.
 180     new_bounds.Scale(root_window_ui_scale_ * root_window_ui_scale_);
 181     // Ignore the origin because RootWindow's insets are handled by
 182     // the transform.
 183     // Floor the size because the bounds is no longer aligned to
 184     // backing pixel when |root_window_scale_| is specified
 185     // (850 height at 1.25 scale becomes 1062.5 for example.)
 186     return gfx::Rect(gfx::ToFlooredSize(new_bounds.size()));
 187   }
 188
 189   gfx::Insets GetHostInsets() const override { return host_insets_; }
 190
 191  private:
 192   ~AshRootWindowTransformer() override {}
 193
 194   aura::Window* root_window_;
 195   gfx::Transform transform_;
 196
 197   // The accurate representation of the inverse of the |transform_|.
 198   // This is used to avoid computation error caused by
 199   // |gfx::Transform::GetInverse|.
 200   gfx::Transform invert_transform_;
 201
 202   // The transform of the root window bounds. This is used to calculate
 203   // the size of root window.
 204   gfx::Transform root_window_bounds_transform_;
 205
 206   // The scale of the root window. See |display_info::ui_scale_|
 207   // for more info.
 208   float root_window_ui_scale_;
 209
 210   gfx::Insets host_insets_;
 211
 212   DISALLOW_COPY_AND_ASSIGN(AshRootWindowTransformer);
 213 };
 214
 215 // RootWindowTransformer for mirror root window. We simply copy the
 216 // texture (bitmap) of the source display into the mirror window, so
 217 // the root window bounds is the same as the source display's
 218 // pixel size (excluding overscan insets).
 219 class MirrorRootWindowTransformer : public RootWindowTransformer {
 220  public:
 221   MirrorRootWindowTransformer(const DisplayInfo& source_display_info,
 222                               const DisplayInfo& mirror_display_info) {
 223     root_bounds_ = gfx::Rect(source_display_info.bounds_in_native().size());
 224     gfx::Rect mirror_display_rect =
 225         gfx::Rect(mirror_display_info.bounds_in_native().size());
 226
 227     bool letterbox = root_bounds_.width() * mirror_display_rect.height() >
 228         root_bounds_.height() * mirror_display_rect.width();
 229     if (letterbox) {
 230       float mirror_scale_ratio =
 231           (static_cast<float>(root_bounds_.width()) /
 232            static_cast<float>(mirror_display_rect.width()));
 233       float inverted_scale = 1.0f / mirror_scale_ratio;
 234       int margin = static_cast<int>(
 235           (mirror_display_rect.height() -
 236            root_bounds_.height() * inverted_scale) / 2);
 237       insets_.Set(0, margin, 0, margin);
 238
 239       transform_.Translate(0,  margin);
 240       transform_.Scale(inverted_scale, inverted_scale);
 241     } else {
 242       float mirror_scale_ratio =
 243           (static_cast<float>(root_bounds_.height()) /
 244            static_cast<float>(mirror_display_rect.height()));
 245       float inverted_scale = 1.0f / mirror_scale_ratio;
 246       int margin = static_cast<int>(
 247           (mirror_display_rect.width() -
 248            root_bounds_.width() * inverted_scale) / 2);
 249       insets_.Set(margin, 0, margin, 0);
 250
 251       transform_.Translate(margin, 0);
 252       transform_.Scale(inverted_scale, inverted_scale);
 253     }
 254   }
 255
 256   // aura::RootWindowTransformer overrides:
 257   gfx::Transform GetTransform() const override { return transform_; }
 258   gfx::Transform GetInverseTransform() const override {
 259     gfx::Transform invert;
 260     CHECK(transform_.GetInverse(&invert));
 261     return invert;
 262   }
 263   gfx::Rect GetRootWindowBounds(const gfx::Size& host_size) const override {
 264     return root_bounds_;
 265   }
 266   gfx::Insets GetHostInsets() const override { return insets_; }
 267
 268  private:
 269   ~MirrorRootWindowTransformer() override {}
 270
 271   gfx::Transform transform_;
 272   gfx::Rect root_bounds_;
 273   gfx::Insets insets_;
 274
 275   DISALLOW_COPY_AND_ASSIGN(MirrorRootWindowTransformer);
 276 };
 277
 278 class PartialBoundsRootWindowTransformer : public RootWindowTransformer {
 279  public:
 280   PartialBoundsRootWindowTransformer(const gfx::Rect& screen_bounds,
 281                                      const gfx::Display& display) {
 282     gfx::SizeF root_size(display.bounds().size());
 283     root_size.Scale(display.device_scale_factor());
 284     root_bounds_ = gfx::Rect(gfx::ToFlooredSize(root_size));
 285
 286     transform_.Translate(-SkIntToMScalar(display.bounds().x()),
 287                          -SkIntToMScalar(display.bounds().y()));
 288   }
 289
 290   // RootWindowTransformer:
 291   gfx::Transform GetTransform() const override { return transform_; }
 292   gfx::Transform GetInverseTransform() const override {
 293     gfx::Transform invert;
 294     CHECK(transform_.GetInverse(&invert));
 295     return invert;
 296   }
 297   gfx::Rect GetRootWindowBounds(const gfx::Size& host_size) const override {
 298     return root_bounds_;
 299   }
 300   gfx::Insets GetHostInsets() const override { return gfx::Insets(); }
 301
 302  private:
 303   gfx::Transform transform_;
 304   gfx::Rect root_bounds_;
 305
 306   DISALLOW_COPY_AND_ASSIGN(PartialBoundsRootWindowTransformer);
 307 };
 308
 309 }  // namespace
 310
 311 RootWindowTransformer* CreateRootWindowTransformerForDisplay(
 312     aura::Window* root,
 313     const gfx::Display& display) {
 314   return new AshRootWindowTransformer(root, display);
 315 }
 316
 317 RootWindowTransformer* CreateRootWindowTransformerForMirroredDisplay(
 318     const DisplayInfo& source_display_info,
 319     const DisplayInfo& mirror_display_info) {
 320   return new MirrorRootWindowTransformer(source_display_info,
 321                                          mirror_display_info);
 322 }
 323
 324 RootWindowTransformer* CreateRootWindowTransformerForUnifiedDesktop(
 325     const gfx::Rect& screen_bounds,
 326     const gfx::Display& display) {
 327   return new PartialBoundsRootWindowTransformer(screen_bounds, display);
 328 }
 329
 330 }  // namespace ash