OneLiner

OneLiner (Graffito)

Create animated signature art in 2D and 3D. Draw a single OneLiner, a multi-stroke ThrowUp, or a ChiselTip marker signature, preview it, and export/share.

Updated: 2026-02-20

Defaults

ChiselTip — Signature Capture (2D)

Whenever you enter the ChiselTip signature capture screen, the display options reset to:

• Length: 60
• Rotation: 15°
• Color: White (white brush, black background)

ChiselTip — Playback (3D)

Whenever you switch into 3D mode in ChiselTip playback, the 3D material controls reset to:

• Radius: 120 mm
• Roughness: 0.50
• Metallic: 0.80
• Diffuse Color: Grey
• Emission Color: Purple

Highlights

• SwiftUI capture + playback
• SceneKit 3D rendering with smooth tube geometry and end-caps
• Animated draw-in sequence, zoom, and optional camera motion
• Options drawer (non-blocking) for brush/material controls
• Export to USDZ (3D) with normalized physical size and Quick Look preview
• ChiselTip can export PNG (2D, transparent background) and preview via Quick Look

App flow

1) Menu (ContentView)

• Tiles: ChiselTip, OneLiner, ThrowUp
• SprayPaint is currently disabled (coming soon)

2) Capture

• OneLiner: draw one continuous stroke → auto-advance to 3D
• ThrowUp: draw multiple strokes; use Undo/Clear; tap Done to proceed
• ChiselTip: timed multi-stroke capture using a rectangular (chisel) brush

3) Viewer / Playback

• ChiselTip (Marker3DView)
  • Toggle between 2D and 3D
  • Replay replays the active mode (2D playback or 3D animation)
  • Options drawer controls 2D brush + 3D material parameters
• OneLiner/ThrowUp (Signature3DView)
  • Animated draw-in of subpaths
  • Options drawer controls radius, roughness, metallic, diffuse/emission colors

4) Export

• Exports are written to your app’s Documents directory and presented in Quick Look.
• While Quick Look is visible, the in-app Export button is hidden to avoid double-export taps.

Export formats & filenames

• OneLiner → OneLine_yyyy-MM-dd_HH-mm-ss.usdz
• ThrowUp → ThrowUp_yyyy-MM-dd_HH-mm-ss.usdz
• ChiselTip (2D mode) → ChiselTip2D_yyyy-MM-dd_HH-mm-ss.png (transparent background)
• ChiselTip (3D mode) → USDZ (see Marker3DView for naming)

Build & run

• Open OneLiner.xcodeproj in Xcode
• Select an iOS device or simulator (see project settings for the minimum iOS version)
• Build and run

Where to find exported files

• On device: Files app → On My iPhone/iPad → OneLiner (or the app’s container name)
• In-app: Quick Look shows immediately after export; use the share button to send/save elsewhere

Architecture at a glance

• OneLiner/OneLinerApp.swift — app entry
• OneLiner/ContentView.swift — menu and navigation
• OneLiner/SignatureCaptureView.swift — drawing capture (single/multi)
• OneLiner/MarkerSignatureCaptureView.swift — ChiselTip capture
• OneLiner/Signature3DView.swift — SceneKit viewer, options drawer, USDZ export + Quick Look
• OneLiner/Marker3DView.swift — ChiselTip viewer (2D/3D) + export
• OneLiner/Marker2DSignatureExporter.swift — ChiselTip 2D PNG renderer/export
• OneLiner/TubeStrokeGeometryBuilder.swift — tube mesh generation
• OneLiner/StrokeSmoother.swift — stroke smoothing
• OneLiner/Signature3DMaterialLibrary.swift — material presets

Troubleshooting

• Duplicate App entry error: ensure only OneLinerApp is annotated with @main
• No Export button during preview: that’s intentional while Quick Look is visible
• Can’t find exported files: export writes to the app’s Documents directory; use Quick Look’s share action to save to Files/iCloud

Privacy

See PRIVACY.md.

License

All rights reserved.