Non-square PCBs are rendered broken

[kb-elmo]

When trying to render a PCB that is not a simple square and instead has multiple different angled sides PCBdraw renders most of the PCB as a transparent area.

Example:

Rendered file:
test_pcb.zip

[yaqwsx]

I suspect that your outline is not continuous and you have small gaps between the arc. PcbDraw expects a continuous outline. This is somewhat addressed in the upcoming v1 release.

[kb-elmo]

I think if the outline wasn't continuous it wouldn't get rendered properly in the KiCAD rendered either and throw an error instead.

But it works perfectly fine in there.

[yaqwsx]

KiCAD renderer tolerates discontinuations up to 0.1mm. This is not what we do; we expect a perfectly continuous outline at the moment. If you want to check for outline continuations, run it through KiKit ­– it will exactly tell you where the discontinuation is.

[kb-elmo]

Like I said there doesn't seem to be any discontinuation in the outline.

I added the example file to my original post btw so you can check it yourself if you don't believe me.

[yaqwsx]

Thank you, having the file will help me to trace the bug (I confirm it is there).

[set-soft]

Just my 2 cents: the edge polygon is OK, because I use PcbDraw to compose a fast print of the PCB in KiBot and I get:

I'm extracting the masks from the file generated by PcbDraw and then composing the result to be similar to what you get from KiCad (using print options).

[JordanAceto]

Hello :)

I also have been having some similar issues when the corners are not square. Below is an image of two very similar, but different boards. In an attempt to troubleshoot I copy-pasted the edge-cuts layer from the good board on the right into the bad board the left using pcb_new, but the odd behavior persisted.

My system is: KiCad 6.0.6 on Ubuntu 22.04

Below is a zip file with two nearly identical minimal boards, as seen above. One of them draws fine and the other has that big weird triangle. Perhaps it can be used as a troubleshooting aid. I was using KiBot when I ran into the issue, and I left some convenience Make and yaml files in there.

pcbdraw_test.zip

Thanks and all the best.

[set-soft]

Hi @JordanAceto !

I found the problem and will be fixed in the PcbDraw that I include with KiBot. The problem is just about the tolerance in the code that joins segments, it was 5 nm and now is 1 µm. The failing case is a 52 nm error in the KiCad SVG generation (rounding issues). PcbDraw is changing a lot and I'm not sure if I'll be able to use the current git code soon.

The patch is here: https://github.com/INTI-CMNB/PcbDraw/commit/e18d42c725f691f751cef78804e9142e12e13911

[JordanAceto]

Hi @set-soft, what you wrote makes perfect sense. I confirm that when I apply your patch the left board from my image above prints correctly. Thank you!

[set-soft]

Hi @JordanAceto and @kb-elmo ! I added a new release to my fork: https://github.com/INTI-CMNB/PcbDraw/releases/tag/v0.9.0-2 including this patch. Is also uploaded it to the KiBot Debian/Ubuntu repo: https://set-soft.github.io/debian/

[yaqwsx]

The change was applied in 2f50ead

[kb-elmo]

Thanks! 😄

[duckyb]

@yaqwsx would it be possible to include this fix in a new release of kikit docker? I would like to have this fix in my github actions automated workflow.

[yaqwsx]

Note that v1 was released, which includes proper edges reconstruction. Also, the KiKit docker image already contains this new version.