screenserver

A horrible hack to serve images across a network for display via screensaver.

Never Asked Questions

Why?

I wanted to implement a screensaver setup that turned a multi-screen configuration into something like Razor and Blade's nightclub on the movie 'Hackers'. Archillect has an excellent selection of cyberpunk-esque animated .gifs but the built-in screensavers on MacOS only show static images. Archillect itself has an excellent "TV" mode but that pulls from a constantly updated stream of animated images and requires an active Internet connection.

screenserver allows you to run a number of independent displays from a curated list of images while being offline. It was written in less time than it took to write this README.

Why is it written in NodeJS?

Good point. I should have written it in Python but wanted to learn a little about NodeJS.

What Operating Systems does it run on?

Any system that has a NodeJS interpreter.

What does it do?

It runs a web server on a configured port and delivers a random image from a local directory, embedded in a simple HTML template and maximized to the screen size as much as possible.

Installation

1. Install NodeJS.

2. Download a selection of images and place them in a directory.

3. Configure the ip address, port, and image directory in screenserver.js.

4. Run node screenserver.js.

5. Configure a screensaver to connect to the server and enjoy.

Configuration for Mac OS

While there are many ways to use this simple tool, I used webviewscreensaver to display the output of screenserver.

screenserver is run as a daemon by putting the following in a file called local.screenserver.plist in /Library/LaunchDaemons/ (root required), customizing "UserName" and "WorkingDirectory" as appropriate.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>local.screenserver.plist</string>

    <key>UserName</key>
    <string>[USERNAME]</string>

    <key>WorkingDirectory</key>
    <string>[PATH_TO_SCRIPT_DIR]</string>

    <key>ProgramArguments</key>
    <array>
        <string>/usr/local/bin/node</string>
        <string>screenserver.js</string>
    </array>

    <key>RunAtLoad</key>
    <true/>

    <key>KeepAlive</key>
    <true/>

</dict>
</plist>

You can then load the service with:

sudo launchctl load /Library/LaunchDaemons/local.screenserver.plist

and start it with:

sudo launchctl start local.screenserver.plist

If you want to stop screenserver running, you can do so with sudo launchctl unload /Library/LaunchDaemons/local.screenserver.plist