Linux/X11 application for the Logitech Spotlight device (and similar devices).
See Download section for binary packages.
I saw the Logitech Spotlight device in action at a conference and liked it immediately. Unfortunately as in a lot of cases, software is only provided for Windows and Mac. The device itself works just fine on Linux, but the cool spotlight feature is done by additional software.
So here it is: a Linux application for the Logitech Spotlight.
The application was mostly tested on Ubuntu 18.04 (GNOME) and OpenSuse 15 (GNOME) but should work on almost any Linux/X11 Desktop. In case you are building the application youself, make sure you have the correct udev rules installed (see pre-requisites section).
With a connection via the USB Dongle Receiver or via Bluetooth, the Logitech Spotlight device will be detected by Linux as a HID device with mouse and keyboard events. As mouse events the device sends relative cursor movements and left button presses. Acting as a keyboard, the device basically just sends left and right arrow key press events when forward or back on the device is pressed.
The mouse events of the detected device is what we are interested in. Since the device is already detected as a mouse input device and able to move the cursor, we simply detect if the Spotlight device is sending mouse move events. If it is sending mouse events, we will 'turn on' the desktop spot.
For more details: Have a look at the source code ;)
This version implemented a virtual device by default (You can still disable it with
--disable-uinput command line option). Projecteur will now grab all device
events and forward it to the virtual 'uniput' device. While this does currently not
change any behavior or feature from
v0.6, this prepares Projecteur for the planned
button mapping feature.
The latest binary packages for some Linux distributions are available for download on bintray. Currently binary packages for Ubuntu, Debian, Fedora, OpenSuse, CentOS and Arch Linux are automatically built.
Note: You can omit setting the
QTDIR variable, CMake will then usually find
the Qt version that comes with the distribution's package management.
> git clone https://github.com/jahnf/projecteur > cd projecteur > mkdir build && cd build > QTDIR=/opt/Qt/5.9.6/gcc_64 cmake .. > make
The input devices detected from the Spotlight device must be readable to the
user running the application. To make this easier there is a udev rule template
file in this repository:
55-projecteur.ruleswill be created from this template in your build directory. Copy that generated file to
sudo udevadm control --reload-rulesand
sudo udevadm triggerto load the rules without a reboot.
qml-modules-qtquick2to satisfy the application's runtime dependencies.
The application menu is accessable via the system tray icon. There you will find the preferences and the menu entry to exit the application. If the system tray icon is missing, see the Troubleshooting section.
Additional to the standard
--version options, there is an option to send
commands to a running instance of Projecteur and the ability to set properties.
Usage: projecteur [option] <Options> -h, --help Show command line usage. --help-all Show complete command line usage with all properties. -v, --version Print application version. --cfg FILE Set custom config file. -d, --device-scan Print device-scan results. -l, --log-level LEVEL Set log level (dbg,inf,wrn,err), default is 'inf'. -D DEVICE Additional accepted device; DEVICE=vendorId:productId -c COMMAND|PROPERTY Send command/property to a running instance. <Commands> spot=[on|off] Turn spotlight on/off. settings=[show|hide] Show/hide preferences dialog. quit Quit the running instance.
All the properties that can be set via the command line, are listed with the
Besides the Logitech Spotlight, similar devices can be used and are supported.
Additional devices can be added to
devices.conf. At CMake configuration time
the project will be configured to support these devices and also create entries
for them in the generated udev-rule file.
Projecteur will also accept devices as supported when added via the
command line option.
projecteur -D 04b3:310c
This will enable devices for Projecteur, but it is up to the user to make sure the device is accessible (via udev rules).
To be able to show transparent windows a compositing manager is necessary. If there is no compositing manager running you will see the spotlight overlay as an opaque window.
comptonor others manually.
xcompmgr -c -t-6 -l-6 -o.1or
Projecteur was developed and tested on GNOME and KDE Desktop environments, but should work on most other desktop environments. If the system tray with the Application Menu is not showing, commands can be send to the application to bring up the preferences dialog, to test the spotlight, quit the application or set spotlight properties. See Command Line Interface.
On some distributions that have a GNOME Desktop by default there is no system tray extensions installed (Fedora for example). You can install the KStatusNotifierItem/AppIndicator Support or the TopIcons Plus GNOME extension to have a system tray that can show the Projecteur tray icon (and also from other applications like Dropbox or Skype).
That is due to the fact how the zoom currently works. A screenshot is taken shortly before the overlay window is shown, and then a magnified section is shown wherever the mouse/spotlight is. If the zoom would be updated while the overlay window is shown, the overlay window it self would show up in the magnified section. That is a general problem, that also other magnifier tools face, although they can get around the problem by showing the magnified content rectangle always in the same position on the screen.
While not developed with Wayland in mind, users reported Projecteur works with
Wayland. If you experience problems, you can try to set the
[email protected]:~/Projecteur/build$ QT_QPA_PLATFORM=wayland ./projecteur Using Wayland-EGL
On Wayland the Zoom feature is currently only implemented on KDE and GNOME. This is done with the help of their respective DBus interfaces for screen capturing. On other environemnts with Wayland, the zoom feature is currently not supported.
If the device shows as not connected, there are some things you can do:
--device-scanoption. This will show you a list of all supported and detected devices and also if they are readable/writable. If a detected device is not readable/writable it is an indicator, that there is something wrong with the installed udev rules.
cat /proc/bus/input/devices | grep -A 5 "Vendor=046d"
/dev/input/event??device file is readable by you.
test -r /dev/input/event19 && echo "SUCCESS" || echo "NOT readable"
Copyright 2018-2020 Jahn Fuchs