fPaint

Free, Open-Source Raster Graphics Editor

A community-driven Flutter app aiming to provide professional-grade drawing and painting tools that rival paid commercial software - completely free and open source.

Built with Flutter for cross-platform excellence, fPaint empowers artists, designers, and creators with powerful raster graphics tools across iOS, Android, macOS, Windows, Linux, and Web from a single codebase.

🎯 Our Mission

To create a free alternative to expensive commercial graphics software through community collaboration. We believe great tools should be accessible to everyone, and Flutter's cross-platform capabilities make this vision possible.

✨ Features

• Professional Drawing Tools - Advanced brushes, pressure sensitivity, and precision controls
• Layer Management - Full layer system with blending modes, opacity, and organization
• Selection Tools - Magic Wand, lasso, rectangle, and advanced selection capabilities
• Color Management - Professional color picker with palettes, gradients, and color harmony
• File Format Support - PNG, JPEG, TIFF, WEBP, HEIC, OpenRaster (ORA), and more
• Cross-Platform - Consistent experience across all major platforms
• Undo/Redo - Robust history system for creative freedom
• Responsive UI - Optimized for touch, mouse, and stylus input

🚀 Join the Revolution

This is more than an app - it's a movement. We're building the future of free graphics software together. Whether you're a:

• Flutter Developer - Help us push the boundaries of what's possible with Flutter
• Graphics Programmer - Implement advanced algorithms and optimizations
• UI/UX Designer - Create intuitive interfaces that inspire creativity
• Artist/Designer - Provide feedback on tools and workflows
• Tester - Help ensure quality across all platforms
• Documentation Writer - Make our project accessible to newcomers

Your contribution matters. Every line of code, every bug report, every feature suggestion brings us closer to replacing paid commercial software with a truly free alternative.

💝 100% Free, No Ads, No Paywalls

Unlike commercial alternatives, fPaint will always remain completely free with:

• 🙅🏼 No ads or monetization
• 🙅🏼 No feature restrictions
• 🙅🏼 No premium tiers
• ✅ Full source code transparency
• ✅ Community-driven development
• ✅ Cross-platform availability

🗺️ Roadmap to Professional Graphics Software

We're building toward feature parity with commercial graphics editors. Current priorities include:

Phase 1: Core Enhancement (Current)

• Multi-layer system with blending modes
• Advanced selection tools (Magic Wand, Lasso)
• Professional color management
• Multiple file format support
• Advanced brush engines (contributions needed!)
• Text tool improvements (contributions needed!)
• Performance optimizations (contributions needed!)

Phase 2: Professional Features

• Non-destructive filters and effects
• Advanced typography and text-on-path
• CMYK color management
• Scripting/automation

Your expertise in any of these areas would accelerate our progress tremendously!

Getting Started

Prerequisites

• Flutter SDK (3.35.7 or higher)
• Dart SDK (3.9.2 or higher)
• Edit and build on macOS, Windows, or Linux
• IDE: VS Code or Android Studio
• iOS Simulator / Android Emulator (for mobile development)

Installation

1. Clone the repository

   git clone https://github.com/vteam-com/fPaint.git

2. Navigate to the project directory

   cd fPaint

3. Install dependencies

   flutter pub get

4. Run the app

   flutter run

Testing

Integration Testing

fPaint includes comprehensive integration tests that demonstrate advanced painting features and multi-layer scene creation. The integration tests use human-like gestures to simulate real user interactions and create complete artwork scenes.

Running Integration Tests

To run the integration tests:

# Run all unit test
flutter test

# Run integration test
./tool/run_integration_test.sh

Test Features

The integration tests demonstrate:

• Multi-layer scene creation: Sky gradients, sun with radiating rays, land, houses, and fences
• Advanced drawing tools: Circles, rectangles, lines with human-like gesture simulation
• Gradient fills: Linear and radial gradients for backgrounds and effects
• Layer management: Creating, switching, and organizing artwork layers
• Selection tools: Circle selection for precise area targeting
• Color management: Dynamic color palette and fill operations

Test Helpers

The integration_test/integration_helpers.dart file provides reusable helper functions for:

• Human-like drawing gestures (circles, rectangles, lines)
• Layer management operations
• Gradient fill operations
• Color picker interactions
• UI element tapping and navigation

Usage

1. Launch the app
2. Choose your preferred brush size and color
3. Start drawing on the canvas
4. Use the SidePanel to:
   • Change colors
   • Adjust brush size
   • Use advanced selection tools such as Magic Wand selection
   • Manage layers efficiently
   • Undo/Redo actions
   • Clear the canvas
   • Save your artwork

Contributing

Code Principles: DRY & SOLID

We follow the DRY (Don't Repeat Yourself) principle—avoid code duplication by extracting reusable logic into functions, classes, or constants.

We also adhere to the SOLID principles:

• Single Responsibility: Each class/module should have one responsibility.
• Open/Closed: Code should be open for extension, closed for modification.
• Liskov Substitution: Subtypes must be substitutable for their base types.
• Interface Segregation: Prefer many small, specific interfaces over large, general ones.
• Dependency Inversion: Depend on abstractions, not concretions.

We welcome contributions! Please see our Contributing Guide for details on how to get started.

CI/CD Pipeline

Every push to main triggers the following automated pipeline:

Push to main
  └─► CI (ci.yml)
       ├─ Analyze (flutter analyze, dart format)
       └─ Test (flutter test --coverage → Codecov)
            │
            ▼ on success
       Deploy Pipeline (firebase-hosting-merge.yml)
       ├─► Build Linux   ─┐
       ├─► Build Windows  ├─ parallel
       ├─► Build macOS   ─┘
       │         │
       │         ▼ all complete
       └─► Build Web + Deploy
            ├─ flutter build web
            ├─ Copy desktop zips into build/web/downloads/
            └─ Deploy to paint.vteam.com (Firebase Hosting)

Workflow	File	Trigger
CI	.github/workflows/ci.yml	Push/PR to main or develop
Deploy	.github/workflows/firebase-hosting-merge.yml	After CI succeeds on main
PR Preview	.github/workflows/firebase-hosting-pull-request.yml	Pull requests
Desktop Only	.github/workflows/build-apps.yml	Manual (workflow_dispatch)

The desktop downloads at paint.vteam.com/downloads/ are built and deployed automatically with each release. The "Available on..." page in the app links directly to these URLs.

Code of Conduct

Please read our Code of Conduct before contributing.

Security

If you discover a security vulnerability, please see our Security Policy.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Screenshots

The OpenRaster (ORA) file format

<?xml version="1.0" encoding="UTF-8"?>
<image xmlns:drawpile="http://paint.vteam.com/"
    xmlns:mypaint="http://mypaint.org/ns/openraster" w="800" h="800" version="0.0.6" xres="72" yres="72" drawpile:framerate="24">
    <stack>
        <layer src="data/layer-0103.png" x="134" y="91" opacity="1.0000" name="birds"/>
        <layer src="data/layer-0100.png" y="268" opacity="1.0000" name="Cloud"/>
        <layer src="data/layer-0101.png" y="579" opacity="1.0000" name="Dirt"/>
        <layer src="data/layer-0102.png" opacity="1.0000" name="sky"/>
        <layer name="Background" src="data/background.png" mypaint:background-tile="data/background-tile.png"/>
    </stack>
</image>

Graph Dependencies

How to generate the above graph. Run these commands on macOS .

dart pub global activate lakos
brew install graphviz
./tool/graph.sh

Please contribute and report issues on the GitHub repository. https://github.com/vteam-com/fPaint