Get the default device scale factor from monitor

ui/aura/monitor_manager.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/aura/monitor_manager.h"
 
 #include <stdio.h>
 
+#include "base/command_line.h"
 #include "base/logging.h"
+#include "base/string_number_conversions.h"
 #include "ui/aura/env.h"
+#include "ui/aura/aura_switches.h"
 #include "ui/aura/monitor_observer.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/root_window_host.h"
 #include "ui/gfx/monitor.h"
 #include "ui/gfx/rect.h"
 
 namespace aura {
 namespace {
 // Default bounds for a monitor.
 static const int kDefaultHostWindowX = 200;
 static const int kDefaultHostWindowY = 200;
 static const int kDefaultHostWindowWidth = 1280;
 static const int kDefaultHostWindowHeight = 1024;
 }  // namespace
 
 // static
 bool MonitorManager::use_fullscreen_host_window_ = false;
 
 // static
-gfx::Monitor MonitorManager::CreateMonitorFromSpec(const std::string& spec) {
+gfx::Monitor MonitorManager::CreateMonitorFromSpec(
+    float device_scale_factor, const std::string& spec) {

[sadrul, 2012/04/30 15:15:49]

one param in a line

   static int synthesized_monitor_id = 1000;
   gfx::Rect bounds(kDefaultHostWindowX, kDefaultHostWindowY,
                    kDefaultHostWindowWidth, kDefaultHostWindowHeight);
   int x = 0, y = 0, width, height;
-  float scale = 1.0f;
+  float scale = device_scale_factor;
   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*%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());
   }
   gfx::Monitor monitor(synthesized_monitor_id++);
   monitor.SetScaleAndBounds(scale, bounds);
   DVLOG(1) << "Monitor bounds=" << bounds.ToString() << ", scale=" << scale;
   return monitor;
 }
 
 // static
 RootWindow* MonitorManager::CreateRootWindowForPrimaryMonitor() {
   MonitorManager* manager = aura::Env::GetInstance()->monitor_manager();
   RootWindow* root =
       manager->CreateRootWindowForMonitor(manager->GetMonitorAt(0));
   if (use_fullscreen_host_window_)
     root->ConfineCursorToWindow();
   return root;
 }
 
-MonitorManager::MonitorManager() {
+MonitorManager::MonitorManager() : default_device_scale_factor_(1.0f) {
+

[sadrul, 2012/04/30 15:15:49]

-newline

+  const CommandLine& command_line = *CommandLine::ForCurrentProcess();
+  if (command_line.HasSwitch(switches::kDefaultDeviceScaleFactor)) {
+    double scale_in_double;
+    base::StringToDouble(
+        command_line.GetSwitchValueASCII(switches::kDefaultDeviceScaleFactor),
+        &scale_in_double);
+    default_device_scale_factor_ = static_cast<float>(scale_in_double);
+  }
 }
 
 MonitorManager::~MonitorManager() {
 }
 
 void MonitorManager::AddObserver(MonitorObserver* observer) {
   observers_.AddObserver(observer);
 }
 
 void MonitorManager::RemoveObserver(MonitorObserver* observer) {
   observers_.RemoveObserver(observer);
 }
 
 void MonitorManager::NotifyBoundsChanged(const gfx::Monitor& monitor) {
   FOR_EACH_OBSERVER(MonitorObserver, observers_,
                     OnMonitorBoundsChanged(monitor));
 }
 
 void MonitorManager::NotifyMonitorAdded(const gfx::Monitor& monitor) {
   FOR_EACH_OBSERVER(MonitorObserver, observers_,
                     OnMonitorAdded(monitor));
 }
 
 void MonitorManager::NotifyMonitorRemoved(const gfx::Monitor& monitor) {
   FOR_EACH_OBSERVER(MonitorObserver, observers_,
                     OnMonitorRemoved(monitor));
 }
 
 }  // namespace aura