Curved paths are missing from silkscreen
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I'm not sure precisely what the problem is here, but I have observed that the G-code for my silkscreens is missing the curved paths.
I've attached a (zipped, to appease github) Gerber file that causes the problem, along with a screenshot of the G-code path as rendered by FreeCAD, and the PCB as rendered by KiCad.
Curiously, the text is fine. It is only the nub on the graphic that is a problem. I wonder if the text is composed of line segments and the nub is a curved path?
This is not a big deal for me, just an observation. The silkscreen is more than usable even without the little nub.
Line 29 of the gerber file appears to be a curved path indeed:
G02X126254000Y-72838000I-1000000J0D01*
This looks very similar to the actual G-code required to form a curved path, so it may be quite an easy fix. Not sure. Maybe isolation routing complicates it. It might be easiest to preprocess the curved path from the Gerber into a bunch of line segments.
Oof, well, this is embarrassing. Apparently I hadn't implemented G02 and G03 for straight line segments.
The parsing code is there and, if I remember correctly, I did the interpolation for regions, I just never got around to adding it in for the linear segments for some reason.
At any rate, it looks to be a quick fix as most of the interpolation etc. is implemented, so it's just about parsing the corresponding G02 and G03 lines correctly.
FYI, the engine for the polygon unions is Angus Johnson's clipperlib which acts on linearlized polygons, so all curves get interpolated to linear segments which are then fed into clipperlib to do polygon unionization.
I've included a picture of what the output is now. I've also added the G03 functionality. This is minimally tested so please keep on the look out for any anomalous behavior.
Thanks for the test Gerber, this greatly speeds up debugging!
Would you mind if I included the Gerber file you provided in the examples or tests?
Thanks, that was fast! Clipperlib sounds cool. The screenshot looks perfect. And yes you are welcome to use the Gerber file. I created it by creating a blank PCB in KiCad and adding a footprint for a DIP-4 socket or something like that.