src/ui/views/widget/desktop_aura/desktop_screen_x11.cc

   1 // Copyright (c) 2012 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/views/widget/desktop_aura/desktop_screen_x11.h"
   6
   7 #include <X11/extensions/Xrandr.h>
   8 #include <X11/Xlib.h>
   9
  10 // It clashes with out RootWindow.
  11 #undef RootWindow
  12
  13 #include "base/debug/trace_event.h"
  14 #include "base/logging.h"
  15 #include "ui/aura/window.h"
  16 #include "ui/aura/window_event_dispatcher.h"
  17 #include "ui/aura/window_tree_host.h"
  18 #include "ui/base/layout.h"
  19 #include "ui/display/util/display_util.h"
  20 #include "ui/display/util/x11/edid_parser_x11.h"
  21 #include "ui/events/platform/platform_event_source.h"
  22 #include "ui/gfx/display.h"
  23 #include "ui/gfx/native_widget_types.h"
  24 #include "ui/gfx/screen.h"
  25 #include "ui/gfx/x/x11_types.h"
  26 #include "ui/views/widget/desktop_aura/desktop_screen.h"
  27 #include "ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h"
  28 #include "ui/views/widget/desktop_aura/x11_topmost_window_finder.h"
  29
  30 namespace {
  31
  32 // The delay to perform configuration after RRNotify.  See the comment
  33 // in |Dispatch()|.
  34 const int64 kConfigureDelayMs = 500;
  35
  36 // TODO(oshima): Consider using gtk-xft-dpi instead.
  37 float GetDeviceScaleFactor(int screen_pixels, int screen_mm) {
  38   const int kCSSDefaultDPI = 96;
  39   const float kInchInMm = 25.4f;
  40
  41   float screen_inches = screen_mm / kInchInMm;
  42   float screen_dpi = screen_pixels / screen_inches;
  43   float scale = screen_dpi / kCSSDefaultDPI;
  44
  45   return ui::GetScaleForScaleFactor(ui::GetSupportedScaleFactor(scale));
  46 }
  47
  48 std::vector<gfx::Display> GetFallbackDisplayList() {
  49   ::XDisplay* display = gfx::GetXDisplay();
  50   ::Screen* screen = DefaultScreenOfDisplay(display);
  51   int width = WidthOfScreen(screen);
  52   int height = HeightOfScreen(screen);
  53   gfx::Size physical_size(WidthMMOfScreen(screen), HeightMMOfScreen(screen));
  54
  55   gfx::Rect bounds_in_pixels(0, 0, width, height);
  56   gfx::Display gfx_display(0, bounds_in_pixels);
  57   if (!gfx::Display::HasForceDeviceScaleFactor() &&
  58       !ui::IsDisplaySizeBlackListed(physical_size)) {
  59     float device_scale_factor = GetDeviceScaleFactor(
  60         width, physical_size.width());
  61     DCHECK_LE(1.0f, device_scale_factor);
  62     gfx_display.SetScaleAndBounds(device_scale_factor, bounds_in_pixels);
  63   }
  64
  65   return std::vector<gfx::Display>(1, gfx_display);
  66 }
  67
  68 }  // namespace
  69
  70 namespace views {
  71
  72 ////////////////////////////////////////////////////////////////////////////////
  73 // DesktopScreenX11, public:
  74
  75 DesktopScreenX11::DesktopScreenX11()
  76     : xdisplay_(gfx::GetXDisplay()),
  77       x_root_window_(DefaultRootWindow(xdisplay_)),
  78       has_xrandr_(false),
  79       xrandr_event_base_(0) {
  80   // We only support 1.3+. There were library changes before this and we should
  81   // use the new interface instead of the 1.2 one.
  82   int randr_version_major = 0;
  83   int randr_version_minor = 0;
  84   has_xrandr_ = XRRQueryVersion(
  85         xdisplay_, &randr_version_major, &randr_version_minor) &&
  86       randr_version_major == 1 &&
  87       randr_version_minor >= 3;
  88
  89   if (has_xrandr_) {
  90     int error_base_ignored = 0;
  91     XRRQueryExtension(xdisplay_, &xrandr_event_base_, &error_base_ignored);
  92
  93     if (ui::PlatformEventSource::GetInstance())
  94       ui::PlatformEventSource::GetInstance()->AddPlatformEventDispatcher(this);
  95     XRRSelectInput(xdisplay_,
  96                    x_root_window_,
  97                    RRScreenChangeNotifyMask |
  98                    RROutputChangeNotifyMask |
  99                    RRCrtcChangeNotifyMask);
 100
 101     displays_ = BuildDisplaysFromXRandRInfo();
 102   } else {
 103     displays_ = GetFallbackDisplayList();
 104   }
 105 }
 106
 107 DesktopScreenX11::~DesktopScreenX11() {
 108   if (has_xrandr_ && ui::PlatformEventSource::GetInstance())
 109     ui::PlatformEventSource::GetInstance()->RemovePlatformEventDispatcher(this);
 110 }
 111
 112 ////////////////////////////////////////////////////////////////////////////////
 113 // DesktopScreenX11, gfx::Screen implementation:
 114
 115 gfx::Point DesktopScreenX11::GetCursorScreenPoint() {
 116   TRACE_EVENT0("views", "DesktopScreenX11::GetCursorScreenPoint()");
 117
 118   XDisplay* display = gfx::GetXDisplay();
 119
 120   ::Window root, child;
 121   int root_x, root_y, win_x, win_y;
 122   unsigned int mask;
 123   XQueryPointer(display,
 124                 DefaultRootWindow(display),
 125                 &root,
 126                 &child,
 127                 &root_x,
 128                 &root_y,
 129                 &win_x,
 130                 &win_y,
 131                 &mask);
 132
 133   return gfx::Point(root_x, root_y);
 134 }
 135
 136 gfx::NativeWindow DesktopScreenX11::GetWindowUnderCursor() {
 137   return GetWindowAtScreenPoint(GetCursorScreenPoint());
 138 }
 139
 140 gfx::NativeWindow DesktopScreenX11::GetWindowAtScreenPoint(
 141     const gfx::Point& point) {
 142   X11TopmostWindowFinder finder;
 143   return finder.FindLocalProcessWindowAt(point, std::set<aura::Window*>());
 144 }
 145
 146 int DesktopScreenX11::GetNumDisplays() const {
 147   return displays_.size();
 148 }
 149
 150 std::vector<gfx::Display> DesktopScreenX11::GetAllDisplays() const {
 151   return displays_;
 152 }
 153
 154 gfx::Display DesktopScreenX11::GetDisplayNearestWindow(
 155     gfx::NativeView window) const {
 156   if (!window)
 157     return GetPrimaryDisplay();
 158
 159   // Getting screen bounds here safely is hard.
 160   //
 161   // You'd think we'd be able to just call window->GetBoundsInScreen(), but we
 162   // can't because |window| (and the associated WindowEventDispatcher*) can be
 163   // partially initialized at this point; WindowEventDispatcher initializations
 164   // call through into GetDisplayNearestWindow(). But the X11 resources are
 165   // created before we create the aura::WindowEventDispatcher. So we ask what
 166   // the DRWHX11 believes the window bounds are instead of going through the
 167   // aura::Window's screen bounds.
 168   aura::WindowTreeHost* host = window->GetHost();
 169   if (host) {
 170     DesktopWindowTreeHostX11* rwh = DesktopWindowTreeHostX11::GetHostForXID(
 171         host->GetAcceleratedWidget());
 172     if (rwh)
 173       return GetDisplayMatching(rwh->GetX11RootWindowBounds());
 174   }
 175
 176   return GetPrimaryDisplay();
 177 }
 178
 179 gfx::Display DesktopScreenX11::GetDisplayNearestPoint(
 180     const gfx::Point& point) const {
 181   for (std::vector<gfx::Display>::const_iterator it = displays_.begin();
 182        it != displays_.end(); ++it) {
 183     if (it->bounds().Contains(point))
 184       return *it;
 185   }
 186
 187   return GetPrimaryDisplay();
 188 }
 189
 190 gfx::Display DesktopScreenX11::GetDisplayMatching(
 191     const gfx::Rect& match_rect) const {
 192   int max_area = 0;
 193   const gfx::Display* matching = NULL;
 194   for (std::vector<gfx::Display>::const_iterator it = displays_.begin();
 195        it != displays_.end(); ++it) {
 196     gfx::Rect intersect = gfx::IntersectRects(it->bounds(), match_rect);
 197     int area = intersect.width() * intersect.height();
 198     if (area > max_area) {
 199       max_area = area;
 200       matching = &*it;
 201     }
 202   }
 203   // Fallback to the primary display if there is no matching display.
 204   return matching ? *matching : GetPrimaryDisplay();
 205 }
 206
 207 gfx::Display DesktopScreenX11::GetPrimaryDisplay() const {
 208   return displays_.front();
 209 }
 210
 211 void DesktopScreenX11::AddObserver(gfx::DisplayObserver* observer) {
 212   change_notifier_.AddObserver(observer);
 213 }
 214
 215 void DesktopScreenX11::RemoveObserver(gfx::DisplayObserver* observer) {
 216   change_notifier_.RemoveObserver(observer);
 217 }
 218
 219 bool DesktopScreenX11::CanDispatchEvent(const ui::PlatformEvent& event) {
 220   return event->type - xrandr_event_base_ == RRScreenChangeNotify ||
 221          event->type - xrandr_event_base_ == RRNotify;
 222 }
 223
 224 uint32_t DesktopScreenX11::DispatchEvent(const ui::PlatformEvent& event) {
 225   if (event->type - xrandr_event_base_ == RRScreenChangeNotify) {
 226     // Pass the event through to xlib.
 227     XRRUpdateConfiguration(event);
 228   } else if (event->type - xrandr_event_base_ == RRNotify) {
 229     // There's some sort of observer dispatch going on here, but I don't think
 230     // it's the screen's?
 231     if (configure_timer_.get() && configure_timer_->IsRunning()) {
 232       configure_timer_->Reset();
 233     } else {
 234       configure_timer_.reset(new base::OneShotTimer<DesktopScreenX11>());
 235       configure_timer_->Start(
 236           FROM_HERE,
 237           base::TimeDelta::FromMilliseconds(kConfigureDelayMs),
 238           this,
 239           &DesktopScreenX11::ConfigureTimerFired);
 240     }
 241   } else {
 242     NOTREACHED();
 243   }
 244
 245   return ui::POST_DISPATCH_NONE;
 246 }
 247
 248 ////////////////////////////////////////////////////////////////////////////////
 249 // DesktopScreenX11, private:
 250
 251 DesktopScreenX11::DesktopScreenX11(
 252     const std::vector<gfx::Display>& test_displays)
 253     : xdisplay_(gfx::GetXDisplay()),
 254       x_root_window_(DefaultRootWindow(xdisplay_)),
 255       has_xrandr_(false),
 256       xrandr_event_base_(0),
 257       displays_(test_displays) {
 258 }
 259
 260 std::vector<gfx::Display> DesktopScreenX11::BuildDisplaysFromXRandRInfo() {
 261   std::vector<gfx::Display> displays;
 262   XRRScreenResources* resources =
 263       XRRGetScreenResourcesCurrent(xdisplay_, x_root_window_);
 264   if (!resources) {
 265     LOG(ERROR) << "XRandR returned no displays. Falling back to Root Window.";
 266     return GetFallbackDisplayList();
 267   }
 268
 269   bool has_work_area = false;
 270   gfx::Rect work_area;
 271   std::vector<int> value;
 272   if (ui::GetIntArrayProperty(x_root_window_, "_NET_WORKAREA", &value) &&
 273       value.size() >= 4) {
 274     work_area = gfx::Rect(value[0], value[1], value[2], value[3]);
 275     has_work_area = true;
 276   }
 277
 278   float device_scale_factor = 1.0f;
 279   for (int i = 0; i < resources->noutput; ++i) {
 280     RROutput output_id = resources->outputs[i];
 281     XRROutputInfo* output_info =
 282         XRRGetOutputInfo(xdisplay_, resources, output_id);
 283
 284     bool is_connected = (output_info->connection == RR_Connected);
 285     if (!is_connected) {
 286       XRRFreeOutputInfo(output_info);
 287       continue;
 288     }
 289
 290     if (output_info->crtc) {
 291       XRRCrtcInfo *crtc = XRRGetCrtcInfo(xdisplay_,
 292                                          resources,
 293                                          output_info->crtc);
 294
 295       int64 display_id = -1;
 296       if (!ui::GetDisplayId(output_id, static_cast<uint8>(i), &display_id)) {
 297         // It isn't ideal, but if we can't parse the EDID data, fallback on the
 298         // display number.
 299         display_id = i;
 300       }
 301
 302       gfx::Rect crtc_bounds(crtc->x, crtc->y, crtc->width, crtc->height);
 303       gfx::Display display(display_id, crtc_bounds);
 304
 305       if (!gfx::Display::HasForceDeviceScaleFactor()) {
 306         if (i == 0 && !ui::IsDisplaySizeBlackListed(
 307             gfx::Size(output_info->mm_width, output_info->mm_height))) {
 308           // As per display scale factor is not supported right now,
 309           // the primary display's scale factor is always used.
 310           device_scale_factor = GetDeviceScaleFactor(crtc->width,
 311                                                      output_info->mm_width);
 312           DCHECK_LE(1.0f, device_scale_factor);
 313         }
 314         display.SetScaleAndBounds(device_scale_factor, crtc_bounds);
 315       }
 316
 317       if (has_work_area) {
 318         gfx::Rect intersection = crtc_bounds;
 319         intersection.Intersect(work_area);
 320         display.set_work_area(intersection);
 321       }
 322
 323       switch (crtc->rotation) {
 324         case RR_Rotate_0:
 325           display.set_rotation(gfx::Display::ROTATE_0);
 326           break;
 327         case RR_Rotate_90:
 328           display.set_rotation(gfx::Display::ROTATE_90);
 329           break;
 330         case RR_Rotate_180:
 331           display.set_rotation(gfx::Display::ROTATE_180);
 332           break;
 333         case RR_Rotate_270:
 334           display.set_rotation(gfx::Display::ROTATE_270);
 335           break;
 336       }
 337
 338       displays.push_back(display);
 339
 340       XRRFreeCrtcInfo(crtc);
 341     }
 342
 343     XRRFreeOutputInfo(output_info);
 344   }
 345
 346   XRRFreeScreenResources(resources);
 347
 348   if (displays.empty())
 349     return GetFallbackDisplayList();
 350
 351   return displays;
 352 }
 353
 354 void DesktopScreenX11::ConfigureTimerFired() {
 355   std::vector<gfx::Display> old_displays = displays_;
 356   displays_ = BuildDisplaysFromXRandRInfo();
 357
 358   change_notifier_.NotifyDisplaysChanged(old_displays, displays_);
 359 }
 360
 361 ////////////////////////////////////////////////////////////////////////////////
 362
 363 gfx::Screen* CreateDesktopScreen() {
 364   return new DesktopScreenX11;
 365 }
 366
 367 }  // namespace views