SketchChair

Design and fabricate your own digitally fabricated furniture

SketchChair is an open-source software tool that allows anyone to easily design and build their own digitally fabricated furniture. Sketch your design, test it with an ergonomic figure, and generate cutting patterns for CNC fabrication - all within minutes.

By: Diatom Studio Contact: hello@diatom.cc Website: sketchchair.cc

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Quick Start

Building

# Clean and compile
ant clean compile

# Build JAR
ant build.standard

# Your compiled application will be in: build/SketchChair-standard.jar

Running

macOS (recommended):

./launch-mac.command

Other platforms:

cd build
java -Djogamp.gluegen.UseTempJarCache=true -jar SketchChair-standard.jar

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Documentation

Detailed JavaDoc documentation for all custom classes can be found at: /doc/index.html

Additional documentation:

• build-windows.md - Windows-specific build instructions
• release-instructions.md - Creating release packages
• processing4-upgrade.md - Processing 4 migration notes

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How It Works

This is a high-level overview of the SketchChair engine:

1. Sketch

SketchChair contains a vector drawing program. When you draw on a SketchPlane, drawings are managed by the cc.sketchchair.sketch package.

2. Build & Calculate

The build command generates all parametric parts of your design:

• The engine examines slice selections added by the user
• The cc.sketchchair.geometry package calculates chair slice forms based on intersections between SketchPlanes
• Additional SketchPlanes are added with slots so pieces fit together
• Multiple slice styles are supported: flat finger-jointed surfaces, waffle forms, etc.

3. 3D Simulation

• Drawings from multiple SketchPlanes combine to create cutting outlines with joining details
• Outlines generate 3D meshes fed to the jBullet physics engine
• Simulation calculates chair position and ergonomic figure interaction
• SketchPlanes are matched to the physically simulated model and rendered

4. Pattern Generation & Export

When producing a design:

• SketchOutlines are generated and passed to the ShapePacking package
• Pieces are automatically packed on sheets of specified size
• Export through ToolPathWriter package in various formats (DXF, G-code, PDF, etc.)

5. Save & Share

• Designs save using SketchChair's custom DOM format
• Each element recursively saves via toXML() methods
• CloudHook package handles uploading to sketchchair.cc
• Server compares designs to create/update database entries

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Code Structure

SketchChair is organized into modular packages that can be used independently:

Core Packages

cc.sketchchair.core

Core SketchChair application code. Ties together geometry, shape packing, and figure libraries.

cc.sketchchair.geometry

Geometry classes for storing design structure and calculating cross slices and slots.

cc.sketchchair.sketch

Drawing functions and classes. Can function as a standalone vector drawing program.

cc.sketchchair.functions

Miscellaneous static utility functions.

cc.sketchchair.ragdoll

Ergonomic figure for testing chair designs.

Additional Packages

cc.sketchchair.environments

2D textures for reference backgrounds on drawing planes.

cc.sketchchair.sketch.gui

GUI assets and components.

cc.sketchchair.triangulate

Delaunay triangulation library for generating 3D meshes from design outlines.

cc.sketchchair.widgets

GUI widgets: layer selector, slice settings, etc.

Custom Libraries

CloudHook

Server communication for uploading chairs and user authentication. Server component written in PHP.

ModalGUI

Custom GUI library with standard components written for SketchChair.

ShapePacking

2D cutting outline packing onto material sheets.

ToolPathWriter

Converts 2D sketch outlines to output formats: G-code, DXF, PDF, etc.

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Technology Stack

Language

Java with the Processing framework

This provides:

• Cross-platform compatibility (Windows, macOS, Linux)
• Potential for web deployment via ProcessingJS/p5.js

Third-Party Libraries

Processing 4.3

• Homepage: http://processing.org/
• License: LGPL
• Note: SketchChair uses a patched core.jar with custom application icons to fix the macOS Dock icon issue with JOGL's NEWT windowing system (see Processing Issue #5123). The original is backed up as core.jar.BACKUP in libProcessing4/.

JOGL 2.x (JOGL, GLUEGEN)

• Homepage: http://jogamp.org/
• Purpose: OpenGL bindings for Java
• Version: 2.6.0 (latest stable, compatible with macOS 15.3+ and Apple Silicon)

jBullet

• Homepage: http://jbullet.advel.cz/
• License: ZLIB
• Purpose: Physics simulation

ToxicLibs

• Homepage: http://toxiclibs.org/
• License: LGPLv2
• Purpose: Geometry utilities

SVG Salamander

• Homepage: http://svgsalamander.java.net/
• License: LGPL
• Purpose: SVG import/export

XOM

• Homepage: http://www.xom.nu/
• License: LGPL
• Purpose: XML processing

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Development

IDE

SketchChair was originally developed using Eclipse IDE.

Build System

Apache Ant (see build.xml)

Java Version

• Current: Java 17+
• Recommended for macOS 15.3+: JDK 25 (for JOGL 2.6.0 compatibility)

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Legacy Mode (Deprecated)

Note: Legacy mode (Processing 1.x) is no longer maintained in current development branches.

Legacy compilation instructions (for reference only)

To compile in legacy mode:

1. Edit src/SETTINGS.java - Change line 106: LEGACY_MODE = true;
2. Edit build.xml:
   • Change line 14: dir="libLegacy"
   • Change line 69: dir="libLegacy"
3. Run: ant build

To compile in current mode:

1. Edit src/SETTINGS.java - Change line 106: LEGACY_MODE = false;
2. Edit build.xml:
   • Change line 14: dir="libCurrent"
   • Change line 69: dir="libCurrent"
3. Run: ant build

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Contributing

SketchChair is open-source and welcomes contributions!

• Issues & Features: GitHub Issues
• Documentation: See /doc/index.html for API docs
• Questions: hello@diatom.cc

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License

See LICENSE.txt for full license information.

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Links

• Website: sketchchair.cc
• Studio: diatom.cc
• Processing: processing.org

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Made with ❤️ by Diatom Studio