Graphite is a free, open-source vector and raster graphics editor with a fully nondestructive editing workflow. It combines layer-based compositing with node-based generative design, enabling procedural content creation. The system is architected as a multi-crate Rust workspace with a desktop application (using Chromium Embedded Framework for UI and wgpu for GPU rendering) and a web frontend (Svelte + Vite compiled to WebAssembly). The core document model is a node graph executed by an interpreted runtime with GPU shader support via rust-gpu. Storage uses a CRDT-based format (`.gdd`) with content-addressed deltas, history, and session state, supporting collaborative editing and undo/redo. The editor features a comprehensive tool system (select, pen, brush, shape, text, etc.), a node graph editor, color management, raw image decoding, and vector path operations. The frontend communicates with the Rust backend through a message-passing architecture with hierarchical message types and a dispatcher pattern. The project also includes a CLI tool for export, a build system (cargo-run), and extensive developer tooling (bisect tool, crate hierarchy visualizer, node documentation generator).
FUXA is a full-stack web-based SCADA/HMI builder and runtime for industrial automation and IoT. It provides a visual editor (Angular + SVG) to create real-time dashboards, connect to field devices via 13+ protocols (Modbus, OPC UA, BACnet, Siemens S7, MQTT, etc.), and manage alarms, data acquisition (DAQ), scripting, scheduling, and user permissions. The backend (Node.js/Express) communicates with the frontend via Socket.IO for real-time device value updates. The system supports multiple time-series databases (SQLite, InfluxDB, QuestDB, TDengine) and can be deployed as a web server, Docker container, or Electron desktop app. It also integrates with Node-RED for low-code automation flows. The architecture is modular with a device driver factory pattern, JWT-based authentication, and a plugin system for extensibility. While the codebase is large and contains some monolithic components, it demonstrates solid engineering practices and has a rich set of reusable UI components and utility patterns.
Pencil is an open-source GUI prototyping tool for creating wireframes and mockups across platforms. It is built as an Electron desktop application with a custom UI framework that includes a canvas for SVG-based shape editing, a stencil/collection system for reusable UI components, and export pipelines to SVG, PDF, ODT, HTML, and PNG. The architecture is a monolith with a main process (app/index.js) managing windows and IPC, and a renderer process handling the UI and canvas interactions. The codebase shows a migration from legacy Mozilla XULRunner to Electron, resulting in a mix of old XUL/XPCOM code and modern JavaScript/Node.js patterns. Key data flows involve loading shape definitions from XML collections, manipulating shapes on an SVG canvas, and serializing documents to custom archive formats (.ep, .epz, .epgz). External dependencies include Electron, various npm packages (adm-zip, archiver, jimp, perfect-freehand), and system fonts. The repository also contains a web-based asset management subsystem (DataTable, MapView) that appears to be a separate concern embedded within the same codebase.