ash/touch/touch_transformer_controller.cc

   1 // Copyright 2014 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/touch/touch_transformer_controller.h"
   6
   7 #include "ash/display/display_controller.h"
   8 #include "ash/display/display_manager.h"
   9 #include "ash/host/ash_window_tree_host.h"
  10 #include "ash/root_window_controller.h"
  11 #include "ash/shell.h"
  12 #include "ui/aura/window_tree_host.h"
  13 #include "ui/display/chromeos/display_configurator.h"
  14 #include "ui/display/types/display_snapshot.h"
  15 #include "ui/events/devices/device_data_manager.h"
  16
  17 namespace ash {
  18
  19 namespace {
  20
  21 DisplayManager* GetDisplayManager() {
  22   return Shell::GetInstance()->display_manager();
  23 }
  24
  25 ui::TouchscreenDevice FindTouchscreenById(unsigned int id) {
  26   const std::vector<ui::TouchscreenDevice>& touchscreens =
  27       ui::DeviceDataManager::GetInstance()->touchscreen_devices();
  28   for (const auto& touchscreen : touchscreens) {
  29     if (touchscreen.id == id)
  30       return touchscreen;
  31   }
  32
  33   return ui::TouchscreenDevice();
  34 }
  35
  36 }  // namespace
  37
  38 // This is to compute the scale ratio for the TouchEvent's radius. The
  39 // configured resolution of the display is not always the same as the touch
  40 // screen's reporting resolution, e.g. the display could be set as
  41 // 1920x1080 while the touchscreen is reporting touch position range at
  42 // 32767x32767. Touch radius is reported in the units the same as touch position
  43 // so we need to scale the touch radius to be compatible with the display's
  44 // resolution. We compute the scale as
  45 // sqrt of (display_area / touchscreen_area)
  46 double TouchTransformerController::GetTouchResolutionScale(
  47     const DisplayInfo& touch_display,
  48     const ui::TouchscreenDevice& touch_device) const {
  49   if (touch_device.id == ui::InputDevice::kInvalidId ||
  50       touch_device.size.IsEmpty() ||
  51       touch_display.bounds_in_native().size().IsEmpty())
  52     return 1.0;
  53
  54   double display_area = touch_display.bounds_in_native().size().GetArea();
  55   double touch_area = touch_device.size.GetArea();
  56   double ratio = std::sqrt(display_area / touch_area);
  57
  58   VLOG(2) << "Display size: "
  59           << touch_display.bounds_in_native().size().ToString()
  60           << ", Touchscreen size: " << touch_device.size.ToString()
  61           << ", Touch radius scale ratio: " << ratio;
  62   return ratio;
  63 }
  64
  65 gfx::Transform TouchTransformerController::GetTouchTransform(
  66     const DisplayInfo& display,
  67     const DisplayInfo& touch_display,
  68     const ui::TouchscreenDevice& touchscreen,
  69     const gfx::Size& framebuffer_size) const {
  70   gfx::SizeF current_size = display.bounds_in_native().size();
  71   gfx::SizeF touch_native_size = touch_display.GetNativeModeSize();
  72 #if defined(USE_OZONE)
  73   gfx::SizeF touch_area = touchscreen.size;
  74 #elif defined(USE_X11)
  75   // On X11 touches are reported in the framebuffer coordinate space.
  76   gfx::SizeF touch_area = framebuffer_size;
  77 #endif
  78
  79   gfx::Transform ctm;
  80
  81   if (current_size.IsEmpty() || touch_native_size.IsEmpty() ||
  82       touch_area.IsEmpty() || touchscreen.id == ui::InputDevice::kInvalidId)
  83     return ctm;
  84
  85 #if defined(USE_OZONE)
  86   // Translate the touch so that it falls within the display bounds.
  87   ctm.Translate(display.bounds_in_native().x(),
  88                 display.bounds_in_native().y());
  89 #endif
  90
  91   // Take care of panel fitting only if supported. Panel fitting is emulated in
  92   // software mirroring mode (display != touch_display).
  93   // If panel fitting is enabled then the aspect ratio is preserved and the
  94   // display is scaled acordingly. In this case blank regions would be present
  95   // in order to center the displayed area.
  96   if (display.is_aspect_preserving_scaling() ||
  97       display.id() != touch_display.id()) {
  98     float touch_native_ar =
  99         touch_native_size.width() / touch_native_size.height();
 100     float current_ar = current_size.width() / current_size.height();
 101
 102     if (current_ar > touch_native_ar) {  // Letterboxing
 103       ctm.Translate(
 104           0, (1 - current_ar / touch_native_ar) * 0.5 * current_size.height());
 105       ctm.Scale(1, current_ar / touch_native_ar);
 106     } else if (touch_native_ar > current_ar) {  // Pillarboxing
 107       ctm.Translate(
 108           (1 - touch_native_ar / current_ar) * 0.5 * current_size.width(), 0);
 109       ctm.Scale(touch_native_ar / current_ar, 1);
 110     }
 111   }
 112
 113   // Take care of scaling between touchscreen area and display resolution.
 114   ctm.Scale(current_size.width() / touch_area.width(),
 115             current_size.height() / touch_area.height());
 116   return ctm;
 117 }
 118
 119 TouchTransformerController::TouchTransformerController() {
 120   Shell::GetInstance()->display_controller()->AddObserver(this);
 121 }
 122
 123 TouchTransformerController::~TouchTransformerController() {
 124   Shell::GetInstance()->display_controller()->RemoveObserver(this);
 125 }
 126
 127 void TouchTransformerController::UpdateTouchTransformer() const {
 128   ui::DeviceDataManager* device_manager = ui::DeviceDataManager::GetInstance();
 129   device_manager->ClearTouchTransformerRecord();
 130
 131   // Display IDs and DisplayInfo for mirror or extended mode.
 132   int64 display1_id = gfx::Display::kInvalidDisplayID;
 133   int64 display2_id = gfx::Display::kInvalidDisplayID;
 134   DisplayInfo display1;
 135   DisplayInfo display2;
 136   // Display ID and DisplayInfo for single display mode.
 137   int64 single_display_id = gfx::Display::kInvalidDisplayID;
 138   DisplayInfo single_display;
 139
 140   DisplayController* display_controller =
 141       Shell::GetInstance()->display_controller();
 142   ui::MultipleDisplayState display_state =
 143       Shell::GetInstance()->display_configurator()->display_state();
 144   if (display_state == ui::MULTIPLE_DISPLAY_STATE_INVALID ||
 145       display_state == ui::MULTIPLE_DISPLAY_STATE_HEADLESS) {
 146     return;
 147   } else if (display_state == ui::MULTIPLE_DISPLAY_STATE_DUAL_MIRROR ||
 148              display_state == ui::MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED) {
 149     DisplayIdPair id_pair = GetDisplayManager()->GetCurrentDisplayIdPair();
 150     display1_id = id_pair.first;
 151     display2_id = id_pair.second;
 152     DCHECK(display1_id != gfx::Display::kInvalidDisplayID &&
 153            display2_id != gfx::Display::kInvalidDisplayID);
 154     display1 = GetDisplayManager()->GetDisplayInfo(display1_id);
 155     display2 = GetDisplayManager()->GetDisplayInfo(display2_id);
 156     device_manager->UpdateTouchRadiusScale(
 157         display1.touch_device_id(),
 158         GetTouchResolutionScale(
 159             display1,
 160             FindTouchscreenById(display1.touch_device_id())));
 161     device_manager->UpdateTouchRadiusScale(
 162         display2.touch_device_id(),
 163         GetTouchResolutionScale(
 164             display2,
 165             FindTouchscreenById(display2.touch_device_id())));
 166   } else {
 167     single_display_id = GetDisplayManager()->first_display_id();
 168     DCHECK(single_display_id != gfx::Display::kInvalidDisplayID);
 169     single_display = GetDisplayManager()->GetDisplayInfo(single_display_id);
 170     device_manager->UpdateTouchRadiusScale(
 171         single_display.touch_device_id(),
 172         GetTouchResolutionScale(
 173             single_display,
 174             FindTouchscreenById(single_display.touch_device_id())));
 175   }
 176
 177   gfx::Size fb_size =
 178       Shell::GetInstance()->display_configurator()->framebuffer_size();
 179
 180   if (display_state == ui::MULTIPLE_DISPLAY_STATE_DUAL_MIRROR) {
 181     // In mirror mode, both displays share the same root window so
 182     // both display ids are associated with the root window.
 183     aura::Window* root = display_controller->GetPrimaryRootWindow();
 184     RootWindowController::ForWindow(root)->ash_host()->UpdateDisplayID(
 185         display1_id, display2_id);
 186     device_manager->UpdateTouchInfoForDisplay(
 187         display1_id, display1.touch_device_id(),
 188         GetTouchTransform(display1, display1,
 189                           FindTouchscreenById(display1.touch_device_id()),
 190                           fb_size));
 191     device_manager->UpdateTouchInfoForDisplay(
 192         display2_id, display2.touch_device_id(),
 193         GetTouchTransform(display2, display2,
 194                           FindTouchscreenById(display2.touch_device_id()),
 195                           fb_size));
 196     return;
 197   }
 198
 199   if (display_state == ui::MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED) {
 200     // In extended but software mirroring mode, ther is only one X root window
 201     // that associates with both displays.
 202     if (GetDisplayManager()->software_mirroring_enabled())  {
 203       aura::Window* root = display_controller->GetPrimaryRootWindow();
 204       RootWindowController::ForWindow(root)->ash_host()->UpdateDisplayID(
 205           display1_id, display2_id);
 206       DisplayInfo source_display =
 207           display_controller->GetPrimaryDisplayId() == display1_id ? display1
 208                                                                    : display2;
 209       // Mapping from framebuffer size to the source display's native
 210       // resolution.
 211       device_manager->UpdateTouchInfoForDisplay(
 212           display1_id, display1.touch_device_id(),
 213           GetTouchTransform(source_display, display1,
 214                             FindTouchscreenById(display1.touch_device_id()),
 215                             fb_size));
 216       device_manager->UpdateTouchInfoForDisplay(
 217           display2_id, display2.touch_device_id(),
 218           GetTouchTransform(source_display, display2,
 219                             FindTouchscreenById(display2.touch_device_id()),
 220                             fb_size));
 221     } else {
 222       // In actual extended mode, each display is associated with one root
 223       // window.
 224       aura::Window* root1 =
 225           display_controller->GetRootWindowForDisplayId(display1_id);
 226       aura::Window* root2 =
 227           display_controller->GetRootWindowForDisplayId(display2_id);
 228       RootWindowController::ForWindow(root1)->ash_host()->UpdateDisplayID(
 229           display1_id, gfx::Display::kInvalidDisplayID);
 230       RootWindowController::ForWindow(root2)->ash_host()->UpdateDisplayID(
 231           display2_id, gfx::Display::kInvalidDisplayID);
 232       // Mapping from framebuffer size to each display's native resolution.
 233       device_manager->UpdateTouchInfoForDisplay(
 234           display1_id, display1.touch_device_id(),
 235           GetTouchTransform(display1, display1,
 236                             FindTouchscreenById(display1.touch_device_id()),
 237                             fb_size));
 238       device_manager->UpdateTouchInfoForDisplay(
 239           display2_id, display2.touch_device_id(),
 240           GetTouchTransform(display2, display2,
 241                             FindTouchscreenById(display2.touch_device_id()),
 242                             fb_size));
 243     }
 244     return;
 245   }
 246
 247   // Single display mode. The root window has one associated display id.
 248   aura::Window* root =
 249       display_controller->GetRootWindowForDisplayId(single_display.id());
 250   RootWindowController::ForWindow(root)->ash_host()->UpdateDisplayID(
 251       single_display.id(), gfx::Display::kInvalidDisplayID);
 252   device_manager->UpdateTouchInfoForDisplay(
 253       single_display_id, single_display.touch_device_id(),
 254       GetTouchTransform(single_display, single_display,
 255                         FindTouchscreenById(single_display.touch_device_id()),
 256                         fb_size));
 257 }
 258
 259 void TouchTransformerController::OnDisplaysInitialized() {
 260   UpdateTouchTransformer();
 261 }
 262
 263 void TouchTransformerController::OnDisplayConfigurationChanged() {
 264   UpdateTouchTransformer();
 265 }
 266
 267 }  // namespace ash