Extends the ScreenCapturer interface for individual display screen cast.

Real implementations for each platform will be added in future CLs.

BUG=2787
R=sergeyu@chromium.org

Review URL: https://webrtc-codereview.appspot.com/6819005

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5386 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/modules/desktop_capture/desktop_capture_types.h

@@ -26,6 +26,11 @@ typedef intptr_t WindowId;
 
 const WindowId kNullWindowId = 0;
 
+typedef int ScreenId;
+
+// The screen id corresponds to all screen combined together.
+const ScreenId kFullDesktopScreenId = -1;
+
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_DESKTOP_CAPTURE_DESKTOP_CAPTURE_TYPES_H_

webrtc/modules/desktop_capture/mouse_cursor_monitor.h

@@ -69,7 +69,8 @@ class MouseCursorMonitor {
   //
   // TODO(sergeyu): Provide a way to select a specific screen.
   static MouseCursorMonitor* CreateForScreen(
-      const DesktopCaptureOptions& options);
+      const DesktopCaptureOptions& options,
+      ScreenId screen);
 
   // Initializes the monitor with the |callback|, which must remain valid until
   // capturer is destroyed.

webrtc/modules/desktop_capture/mouse_cursor_monitor_mac.mm

@@ -211,7 +211,8 @@ MouseCursorMonitor* MouseCursorMonitor::CreateForWindow(
 }
 
 MouseCursorMonitor* MouseCursorMonitor::CreateForScreen(
-    const DesktopCaptureOptions& options) {
+    const DesktopCaptureOptions& options,
+    ScreenId screen) {
   return new MouseCursorMonitorMac(kCGNullWindowID);
 }
 

webrtc/modules/desktop_capture/mouse_cursor_monitor_null.cc

@@ -21,7 +21,8 @@ MouseCursorMonitor* MouseCursorMonitor::CreateForWindow(
 }
 
 MouseCursorMonitor* MouseCursorMonitor::CreateForScreen(
-    const DesktopCaptureOptions& options) {
+    const DesktopCaptureOptions& options,
+    ScreenId screen) {
   return NULL;
 }
 

webrtc/modules/desktop_capture/mouse_cursor_monitor_unittest.cc

@@ -58,7 +58,7 @@ class MouseCursorMonitorTest : public testing::Test,
 
 TEST_F(MouseCursorMonitorTest, MAYBE(FromScreen)) {
   scoped_ptr<MouseCursorMonitor> capturer(MouseCursorMonitor::CreateForScreen(
-      DesktopCaptureOptions::CreateDefault()));
+      DesktopCaptureOptions::CreateDefault(), webrtc::kFullDesktopScreenId));
   assert(capturer.get());
   capturer->Init(this, MouseCursorMonitor::SHAPE_AND_POSITION);
   capturer->Capture();
@@ -109,7 +109,7 @@ TEST_F(MouseCursorMonitorTest, MAYBE(FromWindow)) {
 // Make sure that OnMouseCursorPosition() is not called in the SHAPE_ONLY mode.
 TEST_F(MouseCursorMonitorTest, MAYBE(ShapeOnly)) {
   scoped_ptr<MouseCursorMonitor> capturer(MouseCursorMonitor::CreateForScreen(
-      DesktopCaptureOptions::CreateDefault()));
+      DesktopCaptureOptions::CreateDefault(), webrtc::kFullDesktopScreenId));
   assert(capturer.get());
   capturer->Init(this, MouseCursorMonitor::SHAPE_ONLY);
   capturer->Capture();

webrtc/modules/desktop_capture/mouse_cursor_monitor_win.cc

@@ -105,7 +105,8 @@ MouseCursorMonitor* MouseCursorMonitor::CreateForWindow(
 }
 
 MouseCursorMonitor* MouseCursorMonitor::CreateForScreen(
-    const DesktopCaptureOptions& options) {
+    const DesktopCaptureOptions& options,
+    ScreenId screen) {
   return new MouseCursorMonitorWin(NULL);
 }
 

webrtc/modules/desktop_capture/mouse_cursor_monitor_x11.cc

@@ -214,7 +214,8 @@ MouseCursorMonitor* MouseCursorMonitor::CreateForWindow(
 }
 
 MouseCursorMonitor* MouseCursorMonitor::CreateForScreen(
-    const DesktopCaptureOptions& options) {
+    const DesktopCaptureOptions& options,
+    ScreenId screen) {
   if (!options.x_display())
     return NULL;
   return new MouseCursorMonitorX11(

webrtc/modules/desktop_capture/screen_capturer.h

@@ -11,6 +11,9 @@
 #ifndef WEBRTC_MODULES_DESKTOP_CAPTURE_SCREEN_CAPTURER_H_
 #define WEBRTC_MODULES_DESKTOP_CAPTURE_SCREEN_CAPTURER_H_
 
+#include <vector>
+
+#include "webrtc/modules/desktop_capture/desktop_capture_types.h"
 #include "webrtc/modules/desktop_capture/desktop_capturer.h"
 #include "webrtc/system_wrappers/interface/scoped_ptr.h"
 #include "webrtc/typedefs.h"
@@ -40,6 +43,13 @@ struct MouseCursorShape;
 //    Since data can be read while another capture action is happening.
 class ScreenCapturer : public DesktopCapturer {
  public:
+  // Use a struct to represent a screen although it has only an id for now,
+  // because we may want to add more fields (e.g. description) in the future.
+  struct Screen {
+    ScreenId id;
+  };
+  typedef std::vector<Screen> ScreenList;
+
   // Provides callbacks used by the capturer to pass captured video frames and
   // mouse cursor shapes to the processing pipeline.
   //
@@ -78,6 +88,15 @@ class ScreenCapturer : public DesktopCapturer {
   // remain valid until the capturer is destroyed.
   virtual void SetMouseShapeObserver(
       MouseShapeObserver* mouse_shape_observer) = 0;
+
+  // Get the list of screens (not containing kFullDesktopScreenId). Returns
+  // false in case of a failure.
+  virtual bool GetScreenList(ScreenList* screens) = 0;
+
+  // Select the screen to be captured. Returns false in case of a failure (e.g.
+  // if there is no screen with the specified id). If this is never called, the
+  // full desktop is captured.
+  virtual bool SelectScreen(ScreenId id) = 0;
 };
 
 }  // namespace webrtc

webrtc/modules/desktop_capture/screen_capturer_mac.mm

@@ -136,6 +136,8 @@ class ScreenCapturerMac : public ScreenCapturer {
   virtual void Capture(const DesktopRegion& region) OVERRIDE;
   virtual void SetMouseShapeObserver(
       MouseShapeObserver* mouse_shape_observer) OVERRIDE;
+  virtual bool GetScreenList(ScreenList* screens) OVERRIDE;
+  virtual bool SelectScreen(ScreenId id) OVERRIDE;
 
  private:
   void CaptureCursor();
@@ -415,6 +417,20 @@ void ScreenCapturerMac::SetMouseShapeObserver(
   mouse_shape_observer_ = mouse_shape_observer;
 }
 
+bool ScreenCapturerMac::GetScreenList(ScreenList* screens) {
+  assert(screens->size() == 0);
+  // TODO(jiayl): implement screen enumeration.
+  Screen default_screen;
+  default_screen.id = 0;
+  screens->push_back(default_screen);
+  return true;
+}
+
+bool ScreenCapturerMac::SelectScreen(ScreenId id) {
+  // TODO(jiayl): implement screen selection.
+  return true;
+}
+
 void ScreenCapturerMac::CaptureCursor() {
   if (!mouse_shape_observer_)
     return;

webrtc/modules/desktop_capture/screen_capturer_win.cc

@@ -53,6 +53,8 @@ class ScreenCapturerWin : public ScreenCapturer {
   virtual void Capture(const DesktopRegion& region) OVERRIDE;
   virtual void SetMouseShapeObserver(
       MouseShapeObserver* mouse_shape_observer) OVERRIDE;
+  virtual bool GetScreenList(ScreenList* screens) OVERRIDE;
+  virtual bool SelectScreen(ScreenId id) OVERRIDE;
 
  private:
   // Make sure that the device contexts match the screen configuration.
@@ -204,6 +206,20 @@ void ScreenCapturerWin::SetMouseShapeObserver(
   mouse_shape_observer_ = mouse_shape_observer;
 }
 
+bool ScreenCapturerWin::GetScreenList(ScreenList* screens) {
+  assert(screens->size() == 0);
+  // TODO(jiayl): implement screen enumeration.
+  Screen default_screen;
+  default_screen.id = 0;
+  screens->push_back(default_screen);
+  return true;
+}
+
+bool ScreenCapturerWin::SelectScreen(ScreenId id) {
+  // TODO(jiayl): implement screen selection.
+  return true;
+}
+
 void ScreenCapturerWin::Start(Callback* callback) {
   assert(!callback_);
   assert(callback);

webrtc/modules/desktop_capture/screen_capturer_x11.cc

@@ -57,6 +57,8 @@ class ScreenCapturerLinux : public ScreenCapturer,
   // ScreenCapturer interface.
   virtual void SetMouseShapeObserver(
       MouseShapeObserver* mouse_shape_observer) OVERRIDE;
+  virtual bool GetScreenList(ScreenList* screens) OVERRIDE;
+  virtual bool SelectScreen(ScreenId id) OVERRIDE;
 
  private:
   Display* display() { return options_.x_display()->display(); }
@@ -310,6 +312,20 @@ void ScreenCapturerLinux::SetMouseShapeObserver(
   mouse_shape_observer_ = mouse_shape_observer;
 }
 
+bool ScreenCapturerLinux::GetScreenList(ScreenList* screens) {
+  DCHECK(screens->size() == 0);
+  // TODO(jiayl): implement screen enumeration.
+  Screen default_screen;
+  default_screen.id = 0;
+  screens->push_back(default_screen);
+  return true;
+}
+
+bool ScreenCapturerLinux::SelectScreen(ScreenId id) {
+  // TODO(jiayl): implement screen selection.
+  return true;
+}
+
 bool ScreenCapturerLinux::HandleXEvent(const XEvent& event) {
   if (use_damage_ && (event.type == damage_event_base_ + XDamageNotify)) {
     const XDamageNotifyEvent* damage_event =