An open-source CAD/CAM tool for drawing, preparing toolpaths, and generating machine code.
OpenPostPro brings together a lightweight 2D drawing environment, CAM operations, and configurable Python post-processors. Import a DXF drawing or create geometry directly in the application, prepare machining or cutting operations, then generate output adapted to your machine through a post-processor.
The project is in an early development stage. Some geometry and toolpath algorithms still need improvement, so generated output should always be checked carefully before being used on a real machine.
OpenPostPro includes tools to create and edit 2D geometry directly:
- Points, lines, circles, arcs, ellipses, polylines, splines, and text
- Geometric transformations such as offset, symmetry, scaling, and rotation
- Chamfer operations
- Boolean operations to combine, subtract, or intersect supported shapes
- DXF import for supported drawing entities, including lines, points, circles, arcs, ellipses, polylines, splines, and text
OpenPostPro also supports Python scripts at the CAD level. Scripts can create geometry directly inside the application, making it possible to automate repetitive work or generate complex shapes parametrically instead of drawing every element by hand.
For example, the project includes a demo script that generates oblong holes (slots). Scripts can be adapted or written to create the specific elements your design requires.
This CAD scripting capability is separate from Python post-processors: CAD scripts generate drawing geometry, while post-processors translate CAM operations into machine-specific output.
Create toolpath operations from your drawing, including:
- Follow — follow selected geometry
- Offset — create interior or exterior offsets
- Pocket — generate pocketing toolpaths
- Drilling — configure drilling cycles, including peck drilling, tapping, and boring options
- Spiral — create spiral toolpaths
- Move to — add a positioning move
CAM operations have configurable parameters. Because this is an early release, the results, especially outline and offset calculations, may not be reliable for every shape or machining situation.
Post-processors are written in Python, making machine-output customization accessible without changing the C++ application.
The repository includes generic post-processors for:
- Milling / router
- Plasma cutting
Post-processor settings include output file extension, decimal precision, line numbering, comments, header and footer, coordinate units, and relative or absolute arc-centre coordinates. The plasma post-processor also exposes settings for torch commands, start delay, reference setup, and Z-axis handling.
These are generic starting points, not guaranteed profiles for every controller. Review and adapt the output to your machine and controller before use.
The interface language is managed through key/value files in openpostpro/lang. English, French, and Spanish language resources are included.
OpenPostPro is written in C++20 and uses:
- OpenGL 3 for rendering
- Dear ImGui for the user interface
- GLFW for window and input handling
- GLM for mathematics
- FreeType for font rendering
- Python 3.13 embedded for post-processors and scripts
The current project files and bundled runtime libraries target Windows.
You need:
- The Python 3.13 runtime
- The Microsoft Visual C++ x64 Redistributable
Download or clone the repository, then run the application using a compatible build. The project includes a Visual Studio solution at openpostpro/openpostpro.sln.
When compiling, the copy_libs_output.bat script copies the required runtime resources into the output directory, including fonts, language files, post-processors, scripts, textures, and shaders.
- Install Visual Studio 2022 with C++ desktop development tools.
- Open
openpostpro/openpostpro.sln. - Build the solution for the appropriate x64 configuration.
- Ensure the required resource folders and runtime libraries are present beside the executable. The included
copy_libs_output.bathandles copying the project resources as configured by the solution.
The source contains relatively few Windows-specific parts, and Linux or macOS builds may be possible, but neither has been tested yet.
OpenPostPro is designed with cross-platform compatibility in mind, with very few dependencies on Windows-specific features. The application was successfully compiled and run on Ubuntu 21.04 in the past, using Visual Studio Code. This demonstrates that building and running OpenPostPro on Linux is feasible, although the exact build setup has not yet been documented and may need to be recreated. macOS should also be a possible target, but has not yet been tested. Contributions to restore, document, and validate builds on these platforms are welcome.
OpenPostPro is an early release built as an independent open-source project. The main priority for future improvement is the robustness and precision of geometry and outline calculations. Some algorithms currently use floating-point precision and need further work.
Please treat generated toolpaths and machine code as output that requires verification. Simulate or inspect the program and check machine settings, tool definitions, clearances, feeds, and speeds before running it on physical equipment.
Bug reports, feedback, and contributions are welcome.
OpenPostPro is released under the GNU General Public License v3.0 (GPL-3.0). See LICENSE for the full license text.
- Repository: https://github.com/rebisway/openpostpro
- Contact: contact@rebisway.com
I had great fun building OpenPostPro. I hope you enjoy exploring it, using it, and helping it improve.