DiskLens

Disk space analyser in the spirit of TreeSize / WizTree / WinDirStat – C# on .NET 10, with its own GPU-rendered UI (SkiaSharp, no UI framework) that runs on Windows, Linux and Android, and an NTFS MFT reader that scans a 1.3 TB drive in ~4 seconds.

Features

• Tree view with size, share bar, item count and modification date; keyboard navigation.
• Nested treemap (squarified) with labelled folder frames, type colouring, hover/select sync, zoom by double-click, breadcrumb.
• Details panel: headline numbers, breakdown by file type, largest files.
• Live updates while the scan runs.
• Scanners are plug-ins chosen per target:
  • ntfs-mft – reads the Master File Table directly (Windows, administrator). 3.75 M entries on a 1.3 TB drive in ~3.6 s.
  • generic-walk – portable parallel directory walk on top of FileSystemEnumerator. Works everywhere; ~15 s (warm cache) for the same drive.
• Right-click on Windows opens the real Explorer menu (shell extensions, "Open with", "Send to", "Properties") with DiskLens' zoom/reveal items on top; deletions made there update the tree. Shift+right-click (or right-click elsewhere) gives DiskLens' own menu: open, copy path, zoom, Recycle Bin / delete.
• Custom title bar on Windows (drag, Snap Layouts, double-click maximise all still work), dark and light theme, DPI aware. Event-driven render loop: 0 wake-ups when idle, partial repaints on hover.

Android

The same UI, scanner and treemap run on Android (API 30+). Download DiskLens-x.y.z-android.apk from a release, install it, and grant All files access from the banner so the scan can see the whole device. Tap a folder to expand it, long-press for the menu, the ⓘ button opens the details sheet; rotate for the two-pane layout.

Build it yourself: dotnet workload install android, then dotnet build src/DiskLens.Android -c Release (needs an Android SDK with platform 36 and a JDK 21; dotnet build -t:InstallAndroidDependencies -p:AcceptAndroidSDKLicenses=true fetches the SDK parts).

Build & run

dotnet run --project src/DiskLens.App                 # start with the drive picker
dotnet run --project src/DiskLens.App -- C:\Users     # scan a folder immediately
dotnet run --project src/DiskLens.App -- --light      # light theme
dotnet run --project src/DiskLens.App -- --bench C:\ --scanner ntfs-mft   # headless benchmark + memory stats
dotnet test

Requires the .NET 10 SDK. On Linux you need an OpenGL 3.3 capable driver (Mesa is fine); native SkiaSharp binaries for Linux are pulled in via NuGet.

Architecture

src/
  DiskLens.Core              model, scanner abstractions, treemap layout, statistics – no UI, no platform
  DiskLens.Scanners.Generic  portable walk scanner + DriveInfo volume provider
  DiskLens.Scanners.Windows  NTFS MFT scanner, elevation, Recycle Bin, Explorer menu
  DiskLens.Scanners.Android  storage volumes, "All files access", file ops
  DiskLens.Scanners.Posix    (placeholder for /proc/mounts, statx, ...)
  DiskLens.UI                the toolkit: element tree, flex layout, widgets, animation, touch
  DiskLens.UI.Desktop        Silk.NET window host (GLFW + OpenGL), custom Windows title bar
  DiskLens.Presentation      shell, views, treemap/tree/details controls – shared by every host
  DiskLens.App               desktop composition root
  DiskLens.Android           Android app: activity + GL view hosting the same UI
tests/DiskLens.Tests
tools/DiskLens.IconGen       renders the app icon (PNG + ICO) from code

Model

FsTree is a struct-of-arrays: one ChunkedArray<T> per column (parent, name id, size, flags, …), 40 bytes per node plus a 32-byte side table entry per directory for the aggregates. Chunks never move, so the UI can read the tree while a scanner keeps appending; totals are propagated up with interlocked adds as entries arrive. Names live in a de-duplicated UTF-8 NamePool. 3.75 M nodes take ~210 MB.

Scanners

IFileSystemScanner.ProbeAsync tells the registry how well a scanner fits a target (NotApplicable / Fallback / Supported / Preferred, plus RequiresElevation); the best applicable one wins. Scanners write into an IScanSink, which owns node ids – they never touch the tree directly. Adding a scanner (SMB, restic, S3, …) is one class plus a DI registration.

UI toolkit

Retained element tree with absolute bounds, two-pass flex layout, per-frame animation ticks, and Skia drawing straight into the GL framebuffer. Widgets: labels, buttons, scroll view, virtual rows, text box, progress bar, popups. Fonts: Inter and JetBrains Mono (embedded, OFL). Icons: Lucide paths (ISC).

Licence

MIT for the code. Fonts under the SIL Open Font License, icons under ISC (see src/DiskLens.UI/Assets).