A high-performance infinite canvas sketching & whiteboard app built for mouse and drawing tablets.

Scribl — Features & Capabilities

Active Scratch Layer: Initialized with { desynchronized: true, alpha: true } to reduce rendering latency and enable immediate front-buffer drawing.
Committed Layer: Uses frustum-culled batch vector rendering of cached Path2D strokes to maintain 60–120+ FPS across thousands of elements.

Organic Stroke Smoothing: Natural stroke outlines and tapered endpoints powered by perfect-freehand.
Event Coalescing: Uses getCoalescedEvents() to prevent angular stepping during fast scribbling.
Hardware Stylus Eraser: Recognizes stylus eraser flips using e.buttons === 32.
Strict Palm Rejection: Touch inputs are reserved for pan and zoom, preventing accidental pen marks.

Smooth Pan & Zoom: Navigate the canvas from 10% to 800% with world-coordinate transformations anchored precisely to the cursor.
Dynamic Dot Grid: Automatically scales the background dot grid according to the current zoom level.
Spacebar-to-Pan: Hold Space and drag to glide across the canvas with custom grab cursor feedback.

Smooth Eraser Trail: Displays a clean slate-gray trailing streak that tapers and dissolves over approximately 180ms.
Circular Reticle: Provides a circular cursor that matches the eraser's hit-detection footprint.

Floating Island Toolbar: A bottom-docked interface featuring Select, Pen, Eraser, and Zoom tools.
Dedicated Zoom Tool:
- Scrubby Zoom: Adjust zoom through horizontal dragging.
- Selection Zoom: Draw a selection box to frame a specific canvas area.
Contextual Color Palette: Eight curated color swatches.
Stroke Thickness: Four discrete stroke-width options.
Zoom HUD: Quick zoom presets with keyboard shortcuts:
- 100% — Shift + 0
- Zoom In — +
- Zoom Out — -
Non-Blocking Clear Action: Two-step canvas clearing confirmation.

Multi-Level Undo: Supports Cmd + Z.
Redo: Supports Cmd + Shift + Z and Cmd + Y.
Command Tracking: Maintains history for stroke additions, deletions, and translations.

Debounced Autosave: Automatically saves canvas state to local storage.
Native Document Support: Open and save .scribl JSON documents.
High-Resolution PNG Export: Exports canvas content at 2× resolution, tightly bounded to the actual drawing content.

Native Lua 5.4: Fully customizable through ~/.config/scribl/init.lua, powered by mlua.
Custom Keybindings: Configure keyboard shortcuts using Vim-style notation, including <C-z>, <D-z>, <S-0>, and c.
Customizable Floating Dock: Reorder, customize, and reposition the toolbar to:
- bottom
- top
- left
- right
Live Configuration Reload: Native filesystem watching through notify automatically reloads configuration changes when the Lua file is saved, without reloading the canvas.

Scribl is MIT open-source, and looking for contributors! You can contribute by helping to build shapes, canvas text, a highlighter and much more.