Fixes a small memory leak reported by lsan:
```
Direct leak of 73 byte(s) in 1 object(s) allocated from:
#0 0x7f29825f3e70 in malloc (/lib64/liblsan.so.0+0xee70)
#1 0x7f29824a5729 in XGetWindowProperty (/lib64/libX11.so.6+0x29729)
```
Happy new year to the wonderful Godot community!
We're starting a new decade with a well-established, non-profit, free
and open source game engine, and tons of further improvements in the
pipeline from hundreds of contributors.
Godot will keep getting better, and we're looking forward to all the
games that the community will keep developing and releasing with it.
This makes it possible to know whether the window is focused
at a given time, without having to track the focus state manually
using `NOTIFICATION_WM_FOCUS_IN` and `NOTIFICATION_WM_FOCUS_OUT`.
This partially addresses #33928.
This is a new singleton where camera sources such as webcams or cameras on a mobile phone can register themselves with the Server.
Other parts of Godot can interact with this to obtain images from the camera as textures.
This work includes additions to the Visual Server to use this functionality to present the camera image in the background. This is specifically targetted at AR applications.
The current system for capturing the mouse and generating motion events on X11
has issues with inaccurate and lopsided input. This is because both
XQueryPointer and XWarpPointer work in terms of integer coordinates when the
underlying X11 input driver may be tracking the mouse using subpixel
coordinates. When warping the pointer, the fractional part of the pointer
position is discarded.
To work around this issue, the fix uses raw motion events from XInput 2. These
events report relative motion and are not affected by pointer warping.
Additionally, this means Godot is able to detect motion at a higher resolution
under X11. Because this is raw mouse input, it is not affected by the user's
pointer speed and acceleration settings. This is the same system as SDL2 uses
for its relative motion.
Multitouch input on X requires XInput 2.2. Raw motion events require
XInput 2.0. Since 2.0 is old enough, this is now the minimum requirement to
use Godot on X.
Namely:
[-Wunneeded-internal-declaration]
[-Wunused-comparison]
[-Wunused-const-variable]
[-Wunused-function]
[-Wunused-private-fields]
Fixes the following Clang 7 warnings:
```
editor/plugins/script_editor_plugin.cpp:1417:20: warning: function '_find_node_with_script' is not needed and will not be emitted [-Wunneeded-internal-declaration]
editor/scene_tree_dock.cpp:1859:14: warning: function '_find_last_visible' is not needed and will not be emitted [-Wunneeded-internal-declaration]
modules/gdscript/gdscript_parser.cpp:7838:19: warning: equality comparison result unused [-Wunused-comparison]
scene/resources/mesh.cpp:549:35: warning: unused variable '_array_types' [-Wunused-const-variable]
scene/resources/mesh.cpp:563:18: warning: unused variable '_format_translate' [-Wunused-const-variable]
drivers/gles3/rasterizer_scene_gles3.cpp:54:28: warning: unused function 'store_transform2d' [-Wunused-function]
core/io/file_access_network.h:50:6: warning: private field 'ml' is not used [-Wunused-private-field]
core/io/file_access_zip.h:93:14: warning: private field 'archive' is not used [-Wunused-private-field]
core/io/resource_format_binary.h:122:6: warning: private field 'bin_meta_idx' is not used [-Wunused-private-field]
core/message_queue.h:47:9: warning: private field 'mutex' is not used [-Wunused-private-field]
main/tests/test_gui.cpp:63:11: warning: private field 'control' is not used [-Wunused-private-field]
modules/gdscript/gdscript_parser.h:558:7: warning: private field 'completion_static' is not used [-Wunused-private-field]
platform/x11/os_x11.h:148:11: warning: private field 'ip_unix' is not used [-Wunused-private-field]
platform/x11/os_x11.h:180:7: warning: private field 'net_wm_icon' is not used [-Wunused-private-field]
platform/x11/os_x11.h:189:6: warning: private field 'audio_driver_index' is not used [-Wunused-private-field]
platform/x11/os_x11.h:190:15: warning: private field 'capture_idle' is not used [-Wunused-private-field]
servers/physics/body_pair_sw.h:79:6: warning: private field 'cc' is not used [-Wunused-private-field]
servers/visual/visual_server_raster.h:62:7: warning: private field 'draw_extra_frame' is not used [-Wunused-private-field]
```
This allows more consistency in the manner we include core headers,
where previously there would be a mix of absolute, relative and
include path-dependent includes.
When we start the engine we haven't yet gotten any X11 motion events so
we don't yet know where our mouse cursor is located. Instead we now
query the X server for this information when we start and update the
appropriate values.
In addition when we move the window we also update the mouse position
based off of X server knowledge as we will also not have received any
mouse motion events.
this fixes#8145 (for X11 only)
-Project/Editor settings now show tooltips properly
-Settings thar require restart now will show a restart warning
-Video driver is now visible all the time, can be changed easily
-Added function to request current video driver
Now generating mouse events from touch is optional (on by default) and it's performed by `InputDefault` instead of having each OS abstraction doing it. (*)
The translation algorithm waits for a touch index to be pressed and tracks it translating its events to mouse events until it is raised, while ignoring other pointers.
Furthermore, to avoid an stuck "touch mouse", since not all platforms may report touches raised when the window is unfocused, it checks if touches are still down by the time it's focused again and if so it resets the state of the emulated mouse.
*: In the case of Windows, since it already provides touch-to-mouse translation by itself, "echo" mouse events are filtered out to have it working like the rest.
On X11 a little hack has been needed to avoid a case of a spurious mouse motion event that is generated during touch interaction.
Plus: Improve/fix tracking of current mouse position.
** Summary of changes to settings: **
- `display/window/handheld/emulate_touchscreen` becomes `input/pointing_devices/emulate_touch_from_mouse`
- New setting: `input/pointing_devices/emulate_mouse_from_touch`
Using `misc/scripts/fix_headers.py` on all Godot files.
Some missing header guards were added, and the header inclusion order
was fixed in the Bullet module.
