Canvas Window Composer

Note: This project is in very early development. Expect rough edges, bugs, and breaking changes.

Turns your Windows desktop into an infinite, pannable, zoomable canvas. Middle-click drag to pan all windows, Alt+scroll to zoom.

Features

• Pan — Middle-click drag on desktop, or Alt+middle-click anywhere
• Inertia — Fling to keep sliding, smooth deceleration
• Zoom — Alt+scroll to zoom in/out around the cursor
• Fuzzy search — Alt+S to find and jump to any window
• Minimap — Canvas overview, fades after inactivity
• Virtual desktops — Independent canvas per desktop
• Auto-focus — Camera follows focused windows
• Off-screen hiding — Windows hidden when panned out of view
• System tray — Toggle, reset, exit

Controls

Input	Action
Middle-click drag on desktop	Pan all windows
Alt + middle-click drag anywhere	Pan (works over windows)
Alt + Q	Toggle overview (map-view)
Alt + scroll	Zoom in/out around cursor (opens overview if closed)
Alt + S	Fuzzy window search
Tray menu > Enabled	Toggle the canvas on/off
Tray menu > Refresh	Unclip and redraw all windows

How it works

The overview is a fake desktop made of live DWM thumbnails. When you pan or press Alt+Q, a borderless form per monitor comes up with a D3D11 swap chain. Instead of rendering window contents ourselves, we call DwmRegisterThumbnail for the desktop wallpaper (Progman/WorkerW), every canvas-managed window, and the taskbar(s) — DWM then composites live thumbnails onto the form. We only push destination rects when the camera moves; the thumbnails stay in sync at the source window's own frame rate, with no pixel copy. The real windows stay parked wherever SetWindowRgn clipped them — the overview is a view on top of that state, not a replacement for it.

Pan and zoom share one camera, the overview adds a second on top. In panning mode the overlay is click-through (WS_EX_TRANSPARENT), so middle-click drag keeps driving the real canvas camera and all the thumbnails reflow in real time — including windows that would otherwise be clipped off-screen. In zooming mode (Alt+Q / Alt+scroll) click-through goes off and an HLSL shader draws an adaptive grid, scale marks, and a nebula parallax; a second overview camera decouples from the canvas camera so you can zoom out further than the real screen would allow for a map-level view. Clicking a thumbnail (or arrow-keys + Enter) recenters the canvas on that window and closes the overlay.

Config

A default config.ini is written to %APPDATA%\CanvasWindowComposer\ on first run. Every flag is commented out at its default — uncomment and flip to true to opt out of a feature. Changes are picked up live; no restart. Open the folder via Tray menu > Open Config Directory.

Flag	Default	Effect when true
DisableSearch	false	Don't register the Alt+S fuzzy-search hotkey
DisableAltPan	false	Disable Alt + middle-click drag to pan over windows
DisableGreedyDraw	true	Skip SetWindowRgn clipping of off-screen windows. Keeps Alt-Tab / taskbar thumbnails live at the cost of render work for windows panned out of view
DisableMouseCurve	false	Send raw HID deltas to the canvas (1 count = 1 pixel) instead of applying Windows' pointer-acceleration curve. Use if you've turned off "Enhance pointer precision" and want linear pan
DisableZoomHotkey	false	Don't register Alt+Q for the overview. The overview is still reachable by starting a pan

Requirements

• Windows 10/11
• .NET 8.0+
• NSIS (for installer, optional)

Build

# C# app
dotnet build

# Installer (optional)
Install\build-installer.bat

Author

Devnova — github.com/oreyg

License

MIT