A fast, precise, GPU-accelerated CSG modeler with OpenSCAD-compatible syntax.
ChiselCAD is an open-source 3D CAD modeler for engineers and makers who prefer
code-driven design. It reads OpenSCAD-syntax .scad files and renders them with
a modern Vulkan renderer — giving you a dramatically faster result than
legacy OpenGL-based tools.
It implements most of the OpenSCAD language today — primitives, booleans,
transforms, control flow, user-defined functions/modules, 2D extrusion,
color()/offset()/projection(), and file I/O (include/use/import/
surface/text). See Supported Language below for the
full breakdown and the handful of constructs still missing.
It is not yet a verified drop-in replacement, for two reasons: a few language constructs aren't implemented yet (tracked in docs/roadmap.md, v3), and an ongoing correctness audit has found real bugs — including some common primitive argument forms that currently produce silently wrong geometry. These are tracked individually in GitHub Issues; until the Critical/High-severity ones are resolved, verify output geometry rather than assuming full compatibility.
difference() {
cube([50, 35, 7]);
translate([25, 17.5, -1])
cylinder(h = 9, r = 5.5);
translate([6, 6, -1])
cylinder(h = 9, r = 2.8);
}ChiselCAD vs OpenSCAD at a glance
OpenSCAD ChiselCAD Renderer Legacy OpenGL + OpenCSG Vulkan, multi-light Blinn-Phong + rim lighting (PBR/SSAO planned) Boolean backend CGAL (slow) / Manifold (experimental) Manifold (always on) UI responsiveness Blocks on F6 render Async — UI never freezes Editor Embedded QScintilla External (VS Code) + file watch + diagnostics panel; embedded editor and LSP planned AI assistance None Claude integration (planned) Language coverage Full OpenSCAD Broad subset — most of the language; a few constructs + open correctness bugs remain (see below)
- Vulkan renderer with multi-light Blinn-Phong shading, rim lighting, and ACES tonemapping (PBR + SSAO on the roadmap)
- Async dual-phase preview — instant primitive display while booleans evaluate in the background
- Manifold boolean backend — 100–1000× faster than CGAL
- OpenSCAD-syntax compatible —
.scadfiles work as-is for most of the language (see below) - VS Code integration — edit in VS Code, ChiselCAD hot-reloads on save with live error feedback
- ImGui interface — lightweight, dockable, fast
- Cross-platform — Windows and Linux (macOS planned)
- C++20 throughout
| Category | Supported |
|---|---|
| Primitives (3D) | cube, sphere, cylinder |
| Primitives (2D) | square, circle, polygon, text() |
| Booleans / CSG | union(), difference(), intersection(), hull(), minkowski() |
| Transforms | translate(), rotate(), scale(), mirror(), multmatrix(), color() |
| Control flow | for, if/else, let, ternary ?:, ranges in for |
| Functions & modules | user-defined function/module, children()/$children, named + default args |
| Built-ins | full math set, string/vector helpers (concat, str, len, lookup, rands, ...) |
| 2D → 3D | linear_extrude, rotate_extrude, offset(), projection() |
| File I/O | include <>, use <>, import() (STL), surface() (text .dat) |
| Diagnostics | echo(), assert() |
| Quality | $fn, $fs, $fa (global and per-node) |
| Export | Binary STL |
Known gaps (tracked as docs/roadmap.md v3): CSG modifier
characters # % ! *, list comprehensions and each, polyhedron(),
resize(), general range-literal expressions outside for, nested
extrusion, and import/export formats beyond STL. See the roadmap for details
and the issue tracker
for known correctness bugs currently being fixed.
- CMake 3.25+
- Vulkan SDK 1.3+
- vcpkg
- A C++20 compiler (MSVC 2022, GCC 12+, or Clang 15+)
git clone https://github.com/particlesector/chiselcad.git
cd chiselcad
git submodule update --init --recursive
cmake -B build -DCMAKE_TOOLCHAIN_FILE=$VCPKG_ROOT/scripts/buildsystems/vcpkg.cmake
cmake --build build --config ReleaseThe binary will be at build/chiselcad (Linux) or build/Release/chiselcad.exe (Windows).
All resolved via vcpkg:
| Library | Purpose |
|---|---|
| Vulkan + VMA | GPU rendering |
| GLFW | Window + input |
| ImGui (docking) | UI |
| Manifold | CSG boolean operations |
| GLM | Math |
| spdlog | Logging |
| nlohmann-json | Config |
| ImGuiColorTextEdit | Embedded code editor |
- Open a
.scadfile in VS Code - Launch ChiselCAD and click File → Watch File (or pass the path as an argument)
- ChiselCAD monitors the file — every save triggers an instant re-evaluation
- Errors appear in ChiselCAD's diagnostics panel with file/line/column — click to jump
A full LSP extension for VS Code is planned (see docs/roadmap.md).
| Document | Description |
|---|---|
| docs/architecture.md | Full system architecture, subsystem design, and key decisions |
| docs/roadmap.md | Planned features and future direction |
| CONTRIBUTING.md | How to contribute |
ChiselCAD is in active development. The core rendering pipeline, CSG evaluator, and most of the OpenSCAD language are implemented and working (see Supported Language above). Current focus is closing the remaining language gaps and fixing correctness bugs found by an ongoing audit — both tracked in docs/roadmap.md and GitHub Issues — before making any drop-in-replacement claim.
If you want to follow along or contribute, see CONTRIBUTING.md.
MIT — see LICENSE.
ChiselCAD uses Manifold (Apache 2.0), Dear ImGui (MIT), and other open-source libraries. See docs/architecture.md for the full dependency list.