| // Copyright 2013 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 "remoting/host/desktop_shape_tracker.h" |
| |
| #include <vector> |
| |
| #include "base/memory/scoped_ptr.h" |
| #include "base/win/scoped_gdi_object.h" |
| #include "third_party/webrtc/modules/desktop_capture/desktop_capture_options.h" |
| #include "third_party/webrtc/modules/desktop_capture/desktop_region.h" |
| |
| namespace remoting { |
| |
| namespace { |
| |
| struct EnumDesktopShapeData { |
| EnumDesktopShapeData() |
| : window_region(CreateRectRgn(0, 0, 0, 0)), |
| desktop_region(CreateRectRgn(0, 0, 0, 0)) { |
| } |
| base::win::ScopedRegion window_region; |
| base::win::ScopedRegion desktop_region; |
| }; |
| |
| class DesktopShapeTrackerWin : public DesktopShapeTracker { |
| public: |
| DesktopShapeTrackerWin(); |
| virtual ~DesktopShapeTrackerWin(); |
| |
| virtual void RefreshDesktopShape(); |
| virtual const webrtc::DesktopRegion& desktop_shape(); |
| |
| private: |
| // Callback passed to EnumWindows() to enumerate windows. |
| static BOOL CALLBACK EnumWindowsCallback(HWND window, LPARAM lparam); |
| |
| // The most recently calculated desktop region. |
| webrtc::DesktopRegion desktop_shape_; |
| |
| // Stored to compare with newly calculated desktop shapes, to avoid converting |
| // to an DesktopRegion unless the shape has actually changed. |
| base::win::ScopedRegion old_desktop_region_; |
| |
| DISALLOW_COPY_AND_ASSIGN(DesktopShapeTrackerWin); |
| }; |
| |
| DesktopShapeTrackerWin::DesktopShapeTrackerWin() |
| : old_desktop_region_(CreateRectRgn(0, 0, 0, 0)) { |
| } |
| |
| DesktopShapeTrackerWin::~DesktopShapeTrackerWin() { |
| } |
| |
| void DesktopShapeTrackerWin::RefreshDesktopShape() { |
| // Accumulate a new desktop shape from current window positions. |
| scoped_ptr<EnumDesktopShapeData> shape_data(new EnumDesktopShapeData); |
| if (!EnumWindows(EnumWindowsCallback, (LPARAM)shape_data.get())) { |
| PLOG(ERROR) << "Failed to enumerate windows"; |
| desktop_shape_.Clear(); |
| return; |
| } |
| |
| // If the shape has changed, refresh |desktop_shape_|. |
| if (!EqualRgn(shape_data->desktop_region, old_desktop_region_)) { |
| old_desktop_region_.Set(shape_data->desktop_region.release()); |
| |
| // Determine the size of output buffer required to receive the region. |
| DWORD bytes_size = GetRegionData(old_desktop_region_, 0, NULL); |
| CHECK(bytes_size != 0); |
| |
| // Fetch the Windows RECTs that comprise the region. |
| std::vector<char> buffer(bytes_size); |
| LPRGNDATA region_data = reinterpret_cast<LPRGNDATA>(buffer.data()); |
| DWORD result = GetRegionData(old_desktop_region_, bytes_size, region_data); |
| CHECK(result == bytes_size); |
| const LPRECT rects = reinterpret_cast<LPRECT>(®ion_data->Buffer[0]); |
| |
| // Reset |desktop_shape_| and add new rectangles into it. |
| desktop_shape_.Clear(); |
| for (size_t i = 0; i < region_data->rdh.nCount; ++i) { |
| desktop_shape_.AddRect(webrtc::DesktopRect::MakeLTRB( |
| rects[i].left, rects[i].top, rects[i].right, rects[i].bottom)); |
| } |
| } |
| } |
| |
| const webrtc::DesktopRegion& DesktopShapeTrackerWin::desktop_shape() { |
| return desktop_shape_; |
| } |
| |
| // static |
| BOOL DesktopShapeTrackerWin::EnumWindowsCallback(HWND window, LPARAM lparam) { |
| EnumDesktopShapeData* data = reinterpret_cast<EnumDesktopShapeData*>(lparam); |
| HRGN desktop_region = data->desktop_region.Get(); |
| HRGN window_region = data->window_region.Get(); |
| |
| // Is the window visible? |
| if (!IsWindow(window) || !IsWindowVisible(window) || IsIconic(window)) |
| return TRUE; |
| |
| // Find the desktop position of the window (including non-client-area). |
| RECT window_rect; |
| if (!GetWindowRect(window, &window_rect)) |
| return TRUE; |
| |
| // Find the shape of the window, in window coords. |
| // GetWindowRgn will overwrite the current contents of |window_region|. |
| if (GetWindowRgn(window, window_region) != ERROR) { |
| // Translate the window region into desktop coordinates. |
| OffsetRgn(window_region, window_rect.left, window_rect.top); |
| } else { |
| // Window has no shape, or an error occurred, so assume it's rectangular. |
| SetRectRgn(window_region, window_rect.left, window_rect.top, |
| window_rect.right, window_rect.bottom); |
| } |
| |
| // TODO(wez): If the window is maximized then we should clip it to the |
| // display on which it is maximized. |
| // if (IsZoomed(window)) |
| // CombineRgn(window_region, window_region, screen_region, RGN_AND); |
| |
| // Merge the window region into the accumulated desktop region. Window |
| // regions are combined together before converting the result to |
| // DesktopRegion. It assumed that this approach is more efficient than |
| // converting each window region individually. |
| CombineRgn(desktop_region, desktop_region, window_region, RGN_OR); |
| |
| return TRUE; |
| } |
| |
| } // namespace |
| |
| // static |
| scoped_ptr<DesktopShapeTracker> DesktopShapeTracker::Create( |
| webrtc::DesktopCaptureOptions options) { |
| return scoped_ptr<DesktopShapeTracker>(new DesktopShapeTrackerWin()); |
| } |
| |
| } // namespace remoting |