# BlackScreens

> A free, open source Windows tray app that blacks out the monitors you are not using while a
> fullscreen or borderless game is running. The game keeps its monitor, the monitor with keyboard
> focus stays clear, and every other screen goes dark until you alt tab back out. MIT licensed,
> no account and no telemetry. The one network request it can make is an optional check for a
> newer release, which is off until the user turns it on.

## What it is

- Platform: Windows 10 version 1809 or newer, 64 bit. Built on .NET 10 with WinForms overlays and a WPF settings window.
- Install: a per user installer that needs no admin prompt, a single portable exe, or a small framework dependent zip.
- Cost: free. Source is on GitHub under the MIT license.
- Updates: optional and off by default. The app asks once on first run. When switched on it asks the GitHub releases API once a day, downloads the new build and installs it while no monitor is blacked out.

## How it decides what to cover

A few times a second it looks at the visible top level windows. A window counts as a game when it is
not cloaked, has no title bar or is a popup, fills its monitor to within two pixels, and its process
is not on the denylist. By default only the foreground window can start a blackout, so a game you
alt tabbed away from leaves the desktop alone. These monitors are never covered: the one the game is
on, the one with keyboard focus, and any monitor whitelisted in settings.

## Features

- Solid black on the covered monitors, or a Windows screensaver run in preview mode inside the overlay
- Per monitor whitelist, with an Identify button that flashes a number on every screen
- Process denylist with program icons, so browsers, chat apps and the shell never count as a game
- Pause from the tray menu or a global hotkey, Ctrl + Alt + B by default
- Settings window follows the Windows light or dark theme and accent color
- Correct on mixed DPI desktops, portrait screens and hot plugged displays

## Links

- [Website](https://blackscreens.app/): screenshots, downloads and the current release
- [Source code](https://github.com/zedle/BlackScreens): the full repository
- [Downloads](https://github.com/zedle/BlackScreens/releases/latest): installer, portable exe and zip
- [Readme](https://github.com/zedle/BlackScreens/blob/main/README.md): usage and build instructions
- [Issues](https://github.com/zedle/BlackScreens/issues): bug reports and feature requests