blob: b19e2e46e71065d5b33d92cb7998d75ae940dabc [file] [log] [blame]
* Copyright 2018 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.
#include <X11/X.h>
#include <X11/Xlib.h>
#include <X11/extensions/Xdamage.h>
#include <X11/extensions/Xfixes.h>
#include <X11/extensions/Xrandr.h>
#include <memory>
#include "modules/desktop_capture/desktop_capture_options.h"
#include "modules/desktop_capture/desktop_capturer.h"
#include "modules/desktop_capture/desktop_frame.h"
#include "modules/desktop_capture/desktop_region.h"
#include "modules/desktop_capture/linux/shared_x_display.h"
#include "modules/desktop_capture/linux/x_atom_cache.h"
#include "modules/desktop_capture/linux/x_server_pixel_buffer.h"
#include "modules/desktop_capture/screen_capture_frame_queue.h"
#include "modules/desktop_capture/screen_capturer_helper.h"
#include "modules/desktop_capture/shared_desktop_frame.h"
#include "rtc_base/constructor_magic.h"
namespace webrtc {
// A class to perform video frame capturing for Linux on X11.
// If XDamage is used, this class sets DesktopFrame::updated_region() according
// to the areas reported by XDamage. Otherwise this class does not detect
// DesktopFrame::updated_region(), the field is always set to the entire frame
// rectangle. ScreenCapturerDifferWrapper should be used if that functionality
// is necessary.
class ScreenCapturerX11 : public DesktopCapturer,
public SharedXDisplay::XEventHandler {
~ScreenCapturerX11() override;
static std::unique_ptr<DesktopCapturer> CreateRawScreenCapturer(
const DesktopCaptureOptions& options);
// TODO(ajwong): Do we really want this to be synchronous?
bool Init(const DesktopCaptureOptions& options);
// DesktopCapturer interface.
void Start(Callback* delegate) override;
void CaptureFrame() override;
bool GetSourceList(SourceList* sources) override;
bool SelectSource(SourceId id) override;
Display* display() { return options_.x_display()->display(); }
// SharedXDisplay::XEventHandler interface.
bool HandleXEvent(const XEvent& event) override;
void InitXDamage();
void InitXrandr();
void UpdateMonitors();
// Capture screen pixels to the current buffer in the queue. In the DAMAGE
// case, the ScreenCapturerHelper already holds the list of invalid rectangles
// from HandleXEvent(). In the non-DAMAGE case, this captures the
// whole screen, then calculates some invalid rectangles that include any
// differences between this and the previous capture.
std::unique_ptr<DesktopFrame> CaptureScreen();
// Called when the screen configuration is changed.
void ScreenConfigurationChanged();
// Synchronize the current buffer with |last_buffer_|, by copying pixels from
// the area of |last_invalid_rects|.
// Note this only works on the assumption that kNumBuffers == 2, as
// |last_invalid_rects| holds the differences from the previous buffer and
// the one prior to that (which will then be the current buffer).
void SynchronizeFrame();
void DeinitXlib();
DesktopCaptureOptions options_;
Callback* callback_ = nullptr;
// X11 graphics context.
GC gc_ = nullptr;
Window root_window_ = BadValue;
// XRandR 1.5 monitors.
bool use_randr_ = false;
int randr_event_base_ = 0;
XRRMonitorInfo* monitors_ = nullptr;
int num_monitors_ = 0;
DesktopRect selected_monitor_rect_;
// selected_monitor_name_ will be changed to kFullDesktopScreenId
// by a call to SelectSource() at the end of Init() because
// selected_monitor_rect_ should be updated as well.
// Setting it to kFullDesktopScreenId here might be misleading.
Atom selected_monitor_name_ = 0;
typedef XRRMonitorInfo* (*get_monitors_func)(Display*, Window, Bool, int*);
typedef void (*free_monitors_func)(XRRMonitorInfo*);
get_monitors_func get_monitors_ = nullptr;
free_monitors_func free_monitors_ = nullptr;
// XFixes.
bool has_xfixes_ = false;
int xfixes_event_base_ = -1;
int xfixes_error_base_ = -1;
// XDamage information.
bool use_damage_ = false;
Damage damage_handle_ = 0;
int damage_event_base_ = -1;
int damage_error_base_ = -1;
XserverRegion damage_region_ = 0;
// Access to the X Server's pixel buffer.
XServerPixelBuffer x_server_pixel_buffer_;
// A thread-safe list of invalid rectangles, and the size of the most
// recently captured screen.
ScreenCapturerHelper helper_;
// Queue of the frames buffers.
ScreenCaptureFrameQueue<SharedDesktopFrame> queue_;
// Invalid region from the previous capture. This is used to synchronize the
// current with the last buffer used.
DesktopRegion last_invalid_region_;
std::unique_ptr<XAtomCache> atom_cache_;
} // namespace webrtc