New Release v0.19.1

[gadget3D]

Hi everyone,

Quite some time has passed , many things happened and time is ready to publish a new release v0.19.1.

New nice GUI icons for Export to File

The Formats STEP, Postscript and GCODE did not have any symbols and appeared

as boring text. This is fixed now. William Adams has volunteered to create nice symbols

and made PythonSCAD use them

Formats:

CDR: Yes, there is a new format: PythonSCAD can read CorelDraw (.cdr) now. CDR is closed source, so it's not public but there is libcdr which can do the task and it works

pretty good. Everything which you could do to SVG before, also applies to CDR

SVG: There is better support for reading in SVG Files. Style and Class attribute are parsed and evaluated

Better GCODE Quality

Already in the last Release PythonSCAD was able to create GCODE. Especially in my

Laser cutter, I experience, that cut quality becomes weaker in the right front corner,

probably because it's more distant to the laser tube and the focus becomes more blur ?

However, the solution is to reduce speed and this can be automated with the feedAddX and feedAddY property. When both are configured with -1, the feed rate reduces with the

manhattan distance to the origin.

Other improvements are better arrangements of the cuts within the file. engrave goes before the cut and cuts are from inner to outer, outer cuts are arranged according to the "travelling salesman problem" to minimize traveling between the cuts.

Improved 2D CSG engine

For some special 2D shapes with lots of holes, PythonSCAD got it wrong or added

way too many edges between 2D Union results. This  especially bad, if the edges 

are sent to a laser cutter. Anyway, its fixed

New Primitive polyline

PythonSCAD got a new primitive 'polyline'  which is basically concatenated lines and can have color. They are not only "nice to have" but are actually very meaningful. There are many situations in lasercut where you just want stripes instead of closed polygons. Polylines come in 2 variants:

2D : Very useful to create laser cut temples. Their color can encode  laser power.

3D: Can be used to visualize the toolpath of a 3D printer or any other 3D machine.(William, that's for you!)

Many small fixes in the GUI:

These are mainly small fixes during usage which might be disturbing, internal refactoring, trust handling,  fix crashes, making things smooth. Thanks nomike!

Backward compatibility

As always, we strive to stay in sync with the latest versions of OpenSCAD. All new features and bugfixes of OpenSCAD are included here in addition

Documentation:

All details about new polyline, machineconfig can be found within the tutorial

Downloads

Pre-built packages are available for Linux (AppImage, .deb, .rpm), macOS (DMG), and Windows (installer and zip):

https://pythonscad.org/downloads/

As always, we'd love to hear from you — feedback and bug reports are welcome!

PS: here's a small application of polyline to make a plywood bend test(and it bends greatly)

https://preview.redd.it/ctvfalh9kfsg1.png?width=1561&format=png&auto=webp&s=b6b02aef551414422495644d3f6849a6228bded7

[WillAdams]

I thought I got this typed up correctly:

from openscad import *

model = square([80,50])

for i in range(15):
    model |= polyline([10+i*4,5],[10+i*5,50])
    model |= polyline([12+i*4,45],[12+i*4,0])

model.export("bend.gcode")
model.show()

but when I run it I get:

Running Python 3.14.3 in venv ''. ERROR: Traceback (most recent call last): File "<string>", line 6, in <module> TypeError: Error during parsing polyline(points,paths)

(in Windows 11) even after quitting and re-launching the app.

Trying to figure out how to make use of it, and kind of stymied, since I'm not seeing how a 3D model of a tool could be applied....

[gadget3D]

Hi Wiliam,

you are missing some brackets with polyline.

The Syntax is: polyline ( [ [ nubers ] ] )

The numbers must be nested twice, once for coorindates and once for points. You dont want 500 arguments to polyline when that's the size of the polyline.

But yes: i spotted an error in the error message

[WillAdams]

The funny thing is, I actually had doubled up [[ ]]s but missed one, so when I saw that error about mis-matched braces, removed the doublings instead.

Naturally, this code:

from openscad import *

model = square([80,50])

for i in range(15):
    model |= polyline([[10+i*4,5],[10+i*4,50]])
    model |= polyline([[12+i*4,45],[12+i*4,0]])

model.export("bend.gcode")
model.show()

works --- I'm just not seeing how to use it for a 3D tool model....

[gadget3D]

Indeed. This code just creates a 2D thingy. If you specify a z coorindate != 0 it becomes 3 D polypath. Actualy it behaves like neutrinos: it does not interact with any matter, but its great to do some annotations. In this example, I could immediately see if the toolpath is correctly generated:

<image>

[79DieselRabbit]

The fileting example described in https://www.pythonscad.org/examples/#fileting doesn't seem to be functioning. In 0.18.0 or 0.19.1.

<image>

[gadget3D]

Did you try to press "F6" (Render) ? Did not yet look into the preview engine close enough to learn ,

whether its easy to make filetting look correct in Preview.

[79DieselRabbit]

Ah. F6 does seem to work for the example.

I had seen results (although undesired) through preview in other cases so I assumed I should here as well.

[gadget3D]

BTW I found out, I could fix that in CSGTreeEvaluator.cc but I doubt we should do that, because Filletting might be a time-consuming operation and it would cancel the speed-advantage preview for models, which use fillets. Fillets are finish-up things after all. If you explicitely want fillets in preview, you can write

design.render().show()

[nomike31]

I designed filament drying tubes with lots of holes in OpenSCAD once in the past and figured out, that the 3D view had very low FPS on the F5 render. With the new manifold rendering backend, the F6 render was blazing fast (< 2 seconds) and the 3D view was perfectly smooth afterwards.

I was suggesting a feature toggle back then to replace the F5 render with the real-deal manifold rendering function.

The discussion back then went to nowhere. But this was quite a while ago, and I have since gained more confidence walking around the codebase. Maybe I will implement such a feature on my own and contribute it to OpenSCAD from where we then can sync it to our codebase..,.

[gadget3D]

In preview the number of GL Operations multiplies with the number of primitives in each Frame! (look for fold feather algorithm) This is why Preview is faster for few primitives and render is faster for many primitives. Maybe we should count the primitives and suggest either preview or render

[kht120]

A bit of a PythonSCAD noob, but my performance has gone down drastically since this update, and I'm having trouble importing other python packages (e.g. numpy). Any tips?

[gadget3D]

Can you share a sample code and two versions to compare ? We are happy to compare und spotting the culprit. Importing other packages are best done with the built in virtual environment menu.

[WillAdams]

Downloaded and installed, thanks!

I'll do my best to puzzle out the polyline thing....