"Easy as Pie" CAD (Piecad)

For many years I used OpenSCAD, but the functional language it uses was often a hinderance and its speed was poor. Piecad is my opinionted view of what a good, simple CAD API should look like. It is written in Python. Its primary focus is the creation of models for 3D printing.

To install using pip (virtual environment recommended):

pip install piecad

QuickHelp

Documentation

Examples

Printable CheatSheet

Piecad-Viewer: Piecad has a view function which works like a 3d print (also does 2D). Piecad-Viewer provides the window that displays the model/image from each view call. You can use arrow keys to swtich between the models/images.

Type 'h' in the Piecad-Viewer window for a list of commands.

Piecad-Viewer is installed with Piecad. It is automatically started when you use a view call inside Piecad.

My Piecad development environment.

I have one window where I run vi as my editor.

I have another window that is Piecad-Viewer.

I use the script below to watch for changes in all *.py files, the argument to the script is the name of the main python file. When any python file is written, python is ran on that main python file.

So I use view calls for what I need to see. Edit, then when I write, the pywatch script below causes those views to be displayed.

#!/usr/bin/env python3
import sys
import os
import time
from watchdog.events import FileSystemEventHandler
from watchdog.observers import Observer

class MyEventHandler(FileSystemEventHandler):
    def on_created(self, event):
        pass

    def on_modified(self, event):
        if event.src_path.endswith(".py"):
            print(event)
            os.system(f"python {sys.argv[1]}")

    def on_deleted(self, event):
        pass

    def on_moved(self, event):
        pass

if __name__ == "__main__":
    if len(sys.argv) != 2:
        print("Usage: pywatch _file_")
        sys.exit(1)
    path_to_watch = "."  # Current directory
    event_handler = MyEventHandler()
    observer = Observer()
    observer.schedule(event_handler, path_to_watch, recursive=True)
    observer.start()
    try:
        while True:
            time.sleep(1)
    except KeyboardInterrupt:
        observer.stop()
    observer.join()

CREDITS

Piecad is based on Manifold, a 3D CAD package written in C++. Manifold incorporates Clipper2 for 2D objects. It also uses quickhull for 3d convex hulls. You can see Manifold's web site for other packages that are used.

Piecad uses the trimesh package for mesh loading/saving and for Piecad-Viewer.

Piecad also uses isect_segments-bentley_ottmann to check for polygon self intersections. Also, fontTools and fontPens are used to support text.

We include two fonts: Hack-Regular.tts and Roboto-Regular.tts, see piecad/fonts for the licenses.