Add device scale factor to Monitor

BUG=111990
TEST=none

Review URL: https://chromiumcodereview.appspot.com/9967029

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@131609 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 18 insertions, 4 deletions

diff --git a/ui/aura/monitor.cc b/ui/aura/monitor.cc
index d410a1a..52d64f0 100644
--- a/ui/aura/monitor.cc
+++ b/ui/aura/monitor.cc
@@ -6,7 +6,7 @@
 
 namespace aura {
 
-Monitor::Monitor() {
+Monitor::Monitor() : device_scale_factor_(1.0f) {
 }
 
 Monitor::~Monitor() {
diff --git a/ui/aura/monitor.h b/ui/aura/monitor.h
index 5f04188..496263e 100644
--- a/ui/aura/monitor.h
+++ b/ui/aura/monitor.h
@@ -33,6 +33,15 @@ class AURA_EXPORT Monitor {
   }
   const gfx::Insets& work_area_insets() const { return work_area_insets_; }
 
+  // Output device's pixel scale factor. This specifies how much the
+  // UI should be scaled when the actual output has more pixels than
+  // standard monitors (which is around 100~120dpi.) For aura, this
+  // value is either 1.0 or 2.0, but may return different values on
+  // other platforms.
+  float GetDeviceScaleFactor() const {
+    return device_scale_factor_;
+  }
+
   // Returns the monitor's work area.
   gfx::Rect GetWorkAreaBounds() const;
 
@@ -42,6 +51,8 @@ class AURA_EXPORT Monitor {
 
   gfx::Rect bounds_;
 
+  float device_scale_factor_;
+
   DISALLOW_COPY_AND_ASSIGN(Monitor);
 };
 
diff --git a/ui/aura/monitor_manager.cc b/ui/aura/monitor_manager.cc
index ee0bf52..de23f58 100644
--- a/ui/aura/monitor_manager.cc
+++ b/ui/aura/monitor_manager.cc
@@ -6,6 +6,7 @@
 
 #include <stdio.h>
 
+#include "base/logging.h"
 #include "ui/aura/env.h"
 #include "ui/aura/monitor.h"
 #include "ui/aura/root_window.h"
@@ -29,16 +30,18 @@ Monitor* MonitorManager::CreateMonitorFromSpec(const std::string& spec) {
   gfx::Rect bounds(kDefaultHostWindowX, kDefaultHostWindowY,
                    kDefaultHostWindowWidth, kDefaultHostWindowHeight);
   int x = 0, y = 0, width, height;
-  if (sscanf(spec.c_str(), "%dx%d", &width, &height) == 2) {
+  float scale = 1.0f;
+  if (sscanf(spec.c_str(), "%dx%d*%f", &width, &height, &scale) >= 2) {
     bounds.set_size(gfx::Size(width, height));
-  } else if (sscanf(spec.c_str(), "%d+%d-%dx%d", &x, &y, &width, &height)
-             == 4) {
+  } else if (sscanf(spec.c_str(), "%d+%d-%dx%d*%f", &x, &y, &width, &height,
+                    &scale) >= 4 ) {
     bounds = gfx::Rect(x, y, width, height);
   } else if (use_fullscreen_host_window_) {
     bounds = gfx::Rect(aura::RootWindowHost::GetNativeScreenSize());
   }
   Monitor* monitor = new Monitor();
   monitor->set_bounds(bounds);
+  VLOG(1) << "Monitor bounds=" << bounds.ToString() << ", scale=" << scale;
   return monitor;
 }