search

CadQuery / cadquery

A python parametric CAD scripting framework based on OCCT
https://cadquery.readthedocs.io
Other
3.05k stars 284 forks source link

extend tolerance or precision from sweep function #1152

Closed phiser678 closed 1 year ago

phiser678 commented 1 year ago

The sweep function is acting strange when thin! Anybody can help?

To Reproduce

path= cq.Workplane("XZ").spline([(0,0),(20,100/2),(0,100)]) sweep=cq.Workplane("XY").circle(1).sweep(path)

2022-09-13_11-15 However if I use circle(2.2) it is correct. Seems like precision errors?

Environment

OS: Ubuntu 22.04 Using: Python 3.10.4 cadquery==2.2.0b1 cq_editor/_version.py = "0.3.0dev"

lorenzncode commented 1 year ago

This is an OCCT tessellation issue (duplicate of #969).

Tessellation impacts both STL export and CQ-editor visualization.

See the comment in #969 for STL export workaround using netgen. Then even if you don't need STL you could visualize the model from STL file or export STEP and use another viewer.

phiser678 commented 1 year ago

Thanks for the info, so if I export it to STEP and convert it with netgen to STL it should give the correct result? Let's give that a try!

phiser678 commented 1 year ago

This code produces a valid result!

import netgen.occ as nocc
import netgen.meshing as meshing

s = nocc.OCCGeometry('thintube.step')
m = s.GenerateMesh(perfstepsend=meshing.MeshingStep.MESHSURFACE,maxh=.1,optsteps2d=0)
m.Export('thintube.stl', 'STL Format')

2022-09-14_09-53

lorenzncode commented 1 year ago

Fixed in OCCT7.7.0/OCP7.7.0. Here is STL exported directly from cadquery: image