Weston is the reference implementation of a Wayland compositor.
The table below lists the actions that can be performed through Weston keyboard shortcuts, when the development board is connected to a keyboard.
It must be noted that:
- <modifier-key> in the table below corresponds to the key used for common bindings. It is defined by binding-modifier=<modifier-key> in the /etc/xdg/weston/weston.ini file. Possible values for <modifier-key> are:
- "super", i.e. Windows key between "ctrl" and "alt" (default Weston value)
- "ctrl" (default value in STMicroelectronics images)
- "alt"
- "none"
- The shortcuts are defined in desktop-shell/shell.c[1] file (shell_add_bindings() function)
- Some shortcuts require that both a keyboard and a mouse are connected to the development board
- Some shortcuts require that several workspaces are defined. The number of workspaces is defined by num-workspaces=<num-workspaces> in the /etc/xdg/weston/weston.ini file. The maximum number of workspaces is 6. If num-workspaces is not set, one single workspace is configured.
- The left mouse button allows the activation of a window.
Before proceeding, it is recommended to
- check the <modifier-key> value:
grep binding-modifier /etc/xdg/weston/weston.ini
binding-modifier=ctrl
- check the <num-workspaces> value:
grep num-workspaces /etc/xdg/weston/weston.ini
num-workspaces=6
| Command | Action | Condition(s) |
|---|---|---|
| ctrl + alt + backspace | Kill Weston | Keyboard |
| super + scroll | Zoom in / out the desktop | Keyboard + mouse |
| super + alt + scroll | Change activated window opacity | Keyboard + mouse |
| <modifier-key> + page up / page down | Zoom in / out the desktop | Keyboard |
| <modifier-key> + shift + f | Put activated window fullscreen | Keyboard |
| <modifier-key> + left mouse button | Move activated window | Keyboard + mouse |
| <modifier-key> + middle mouse button | Rotate activated window | Keyboard + mouse |
| <modifier-key> + right mouse button | Resize activated window | Keyboard + mouse |
| <modifier-key> + shift + left mouse button | Resize activated window | Keyboard + mouse |
| <modifier-key> + tab | Switch windows | Keyboard |
| <modifier-key> + k | Kill activated window | Keyboard |
| <modifier-key> + key up / key down | Switch to previous / next workspace | Keyboard + workspaces |
| <modifier-key> + shift + key up / key down | Move activated window to previous / next workspace | Keyboard + workspaces |
| <modifier-key> + Fn | Switch to workspace n | Keyboard + workspaces |
| super + s | Capture a screenshot (see details below) | Keyboard |
| super + r | Start / stop recording a screencast (see details below) | Keyboard |
Additional shortcuts can be found on internet.
1. Capturing a screenshot[edit | edit source]
- Refer to the table above for the command to be used.
- The captured picture named "wayland-screenshot-*.png" (PNG format) is automatically stored in "/home/weston" or "/home/root" or "/" depending on the Weston configuration.
- Copy the screenshot from the board to the host PC in the <file-path> directory (for example with the scp command).
scp root@<ip address>:/home/weston/wayland-screenshot-*.png <file-path>/
Note: a screenshot capture is also named a snapshot or a screen capture.
 Information
|
| The above screenshot capture procedure requires a physical keyboard. If you are more interested in using the Weston debug tool named weston-screenshooter, please read How to make a screen capture in Weston. |
2. Recording a screencast[edit | edit source]
- Refer to the table above for the command to be used.
- The recorded screencast named "capture.wcap" (WCAP format) is automatically stored in "/home/weston" or "/home/root" or "/" depending on the Weston configuration. The WCAP format is a lossless video format specific to Weston (only the frame differences are recorded).
- To play the recorded screencast, convert it to a format that can be interpreted by any video player (e.g. VP8). Three steps are required:
- On the board, convert the WCAP file into a YUV file using wcap-decode:
wcap-decode capture.wcap --yuv4mpeg2 > capture.y4m
- Copy the YUV file from the board to the host PC in the <file-path> directory (for example with the scp command):
scp root@<ip address>:/capture.y4m <file-path>/
- On the host PC, transcode the YUV file to any other well-known format (e.g. VP8) using ffmpeg:
ffmpeg -i capture.y4m -c:v libvpx -b:v 1M capture.webm
- Optionally, choose a higher bitrate (-b:v 1M means a target bitrate of 1 MBit/s) if a better quality is required. Optionally, use the transpose parameter when a 90 degree clockwise rotation is needed:
ffmpeg -i capture.y4m -vf transpose=1 -c:v libvpx -b:v 1M capture.webm
| Information
|
| Note that the YUV file size might be huge if the recording is long (see example below). |
Example:
- On the board: a 5-second screencast is recorded
wcap-decode capture.wcap --yuv4mpeg2 > capture.y4m
wcap file: size 720x1280, 192 frames
ls -l capture.*
-rw-r--r-- 1 8246868 Dec 13 14:58 capture.wcap
-rw-r--r-- 1 167821312 Dec 13 14:59 capture.y4m
- On the host PC
scp root@<ip address>:/capture.y4m .
ffmpeg -i capture.y4m -vf transpose=1 -c:v libvpx -b:v 1M capture.webm
ls -l capture.*
-rw-r--r-- 1 104470 Feb 8 11:01 capture.webm
-rw-r--r-- 1 167821312 Feb 8 10:56 capture.y4m
References list:
- ↑ https://cgit.freedesktop.org/wayland/weston/tree/desktop-shell/shell.c Weston Wayland Compositor official git