Compono

Grid based window placement overlay for Windows.

Overview

Compono is a lightweight, high-performance window manager and placement overlay for Windows. Drag a window to any screen edge or use hotkeys to snap, resize, or navigate windows across a configurable grid.

Unlike default Windows Snap, Compono applies direct SetWindowPos geometry, reliably managing elevated processes (Command Prompt, PowerShell, Windows Terminal), WinUI applications, and XAML Island windows across multi-monitor setups.

Screenshots

Edge Detection & Halo Trigger	Custom Rectangle Selection
Screen edge dwell detection triggers the grid overlay.	Click and drag to trace your exact target window rectangle.

Features

• Fast Edge Dwell Detection: Drag any window to a screen edge and hold for 250 ms to open the full-screen grid.
• Custom Rectangle Drawing: Drop the window on the grid, draw any target rectangle, and release to place.
• Keyboard Snapping (Ctrl+Alt+Arrows): Instant cycling between halves, quarters, two-thirds, corners, and full screen.
• Grid Navigation (Alt+Arrows): Move windows cell-by-cell on the grid using arrow keys.
• Multi-Monitor Seamless Transition: Moving a window past screen boundaries jumps directly to the adjacent monitor.
• Quick Close (Escape & Top-Right Button): Press Esc at any time or click the top-right cell (marked with a red cross) to exit the grid immediately.
• Windows Snap Integration: Toggle native Windows Snap on or off directly from the tray with clean Explorer reload.
• Multi-Monitor and Per-Monitor DPI Aware: Hardware-accelerated Direct2D and DirectComposition rendering.
• Bilingual: French and English interface automatically matching your system locale.

Shortcuts

Shortcut	Action	Description
Win+Alt+G	Toggle grid overlay	Opens or closes the placement grid on the active monitor
Ctrl+Alt+Left	Snap horizontal left	Cycles: 1/2 (50%) -> 1/4 (25%) -> 2/3 (66.6%) -> 1/2 (100% height)
Ctrl+Alt+Right	Snap horizontal right	Cycles: 1/2 (50%) -> 1/4 (25%) -> 2/3 (66.6%) -> 1/2 (100% height)
Ctrl+Alt+Up (from side)	Snap corner / top half	Cycles: Top corner (1/4) -> Fine corner (1/8) -> Full top half (1/2) -> Full screen
Ctrl+Alt+Down (from side)	Snap corner / bottom half	Cycles: Bottom corner (1/4) -> Fine corner (1/8) -> Full bottom half (1/2)
Ctrl+Alt+Up (direct)	Snap vertical top	Cycles: Top half (50%) -> Top quarter (25%) -> Full screen (100%)
Ctrl+Alt+Down (direct)	Snap vertical bottom	Cycles: Bottom half (50%) -> Bottom quarter (25%)
Alt + Arrows (hold Alt)	Grid cell movement	Moves the active window step-by-step across grid cells
Alt + Arrows (at screen edge)	Cross-monitor jump	Jumps window and grid focus to the adjacent screen
Esc	Exit / cancel grid	Closes the active grid overlay and cancels placement
Release Alt	Confirm keyboard placement	Locks window position on the grid and hides the overlay

Usage

1. Edge Drag and Drop

1. Drag any window to a screen edge (left, right, top, or bottom) and hold for 250 ms.
2. The grid overlay appears with an edge halo. Release the mouse button.
3. Click and drag across grid cells to define your destination rectangle.
4. Release the click: the window is placed and focused.
5. To cancel: click the top-right cell marked with ✕, right-click, or press Esc.

2. Keyboard Grid Navigation

1. Snap a window using Ctrl+Alt+Arrows.
2. Release Ctrl while keeping Alt pressed.
3. Press any arrow key (Left, Right, Up, Down) to step the window across the grid.
4. If you reach the edge of a monitor, pressing the arrow key again moves the window to the adjacent monitor.
5. Release Alt to lock the window into position.

3. Tray Menu

Click or right-click the Compono icon in the taskbar notification area:

• Show grid / Hide grid (Win+Alt+G).
• Start with Windows: Toggle automatic startup via HKCU\Software\Microsoft\Windows\CurrentVersion\Run.
• Windows Snap: Toggle OS native window snapping (updates registry and triggers SPI_SETWINARRANGEMENT).
• Quit: Exits Compono and unregisters hooks.

Administrator Privileges

Compono requests requireAdministrator via its application manifest. Under Windows User Interface Privilege Isolation (UIPI), standard processes cannot move or resize windows belonging to elevated processes. Running Compono elevated allows it to manage all desktop windows, including administrator consoles and terminals.

Installation

1. Download the latest release from the Releases page.
2. Extract the archive.
3. Run compono.exe (accept the standard UAC elevation prompt).

Configuration

Compono creates its configuration in %APPDATA%\Compono\config.toml:

lang = "en" # "en" or "fr"

If omitted, Compono automatically follows the Windows system language.

Building from Source

Requires Rust 1.85 or later on Windows:

cargo build --release

The optimized binary is created at target/release/compono.exe.

License

MIT License. See LICENSE for details.