[Chromoting] Improve DirectX capturer to support multiple outputs

webrtc/modules/desktop_capture/win/dxgi_texture_mapping.h

+/*
+ *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef WEBRTC_MODULES_DESKTOP_CAPTURE_WIN_DXGI_TEXTURE_MAPPING_H_
+#define WEBRTC_MODULES_DESKTOP_CAPTURE_WIN_DXGI_TEXTURE_MAPPING_H_
+
+#include <D3D11.h>
+#include <DXGI1_2.h>
+
+#include "webrtc/modules/desktop_capture/desktop_geometry.h"
+#include "webrtc/modules/desktop_capture/desktop_region.h"
+#include "webrtc/modules/desktop_capture/win/dxgi_texture.h"
+
+namespace webrtc {
+
+// A DxgiTexture which directly maps bitmap from IDXGIResource. This class is
+// used when DXGI_OUTDUPL_DESC.DesktopImageInSystemMemory is true. (This usually
+// means the video card shares main memory with CPU, instead of having its own
+// individual memory.)
+class DxgiTextureMapping : public DxgiTexture {
+ public:
+  // Creates a DxgiTextureMapping instance. Caller must maintain the lifetime
+  // of input duplication to make sure it outlives this instance.
+  DxgiTextureMapping(const DesktopRect& desktop_rect,
+                     IDXGIOutputDuplication* duplication);
+
+  ~DxgiTextureMapping() override;
+
+  bool CopyFrom(const DXGI_OUTDUPL_FRAME_INFO& frame_info,
+                IDXGIResource* resource,
+                const DesktopRegion& region) override;
+
+  bool DoRelease() override;
+
+ private:
+  IDXGIOutputDuplication* const duplication_;
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_DESKTOP_CAPTURE_WIN_DXGI_TEXTURE_MAPPING_H_