kicad-developers team mailing list archive

[jp charras <jp.charras@xxxxxxxxxx>]

Le 21/06/2019 à 14:57, Seth Hillbrand a écrit :
> Hi Wayne-
> 
> I don't think that the relief chamfering is controlled by that option. 
> We also don't chamfer the connection on the way into the pad, so I'd
> tend to agree with Jeff that the extra corner chamfer on only one side
> of the connection might be unnecessary.
> 
> It looks like the original knockout code was JP's so I'd be curious to
> hear why they were originally added.
> 
> -Seth
> 

The main reason was a problem with the polygon library Kicad was using
at this time.

This library frequently created bad polygon shapes due to thermal shapes
when filling a zone.

I noticed the bad polygon shapes were much less frequent with the
chamfered shapes, and when the thermal stubs shape is a X instead of a +
for round pads.

Beside, chamfers avoid acute angles in thermal reliefs, especially for
round (and oval) shapes.

They are not mandatory, because I am pretty sure most of other ECAD
tools do not use chamfers, but they create a better shape.

For me, the main (blocking) issue with the new algo is the calculation time.

-- 
Jean-Pierre CHARRAS