kicad-developers team mailing list archive

[easyw <easyw@xxxxxxxxxxxx>]

On 07/10/2019 9:02 PM, Wayne Stambaugh wrote:
> Don't forget, this will impact all import from and export to 3rd party
> file formats so it's not going to be a trivial change.
>
> Wayne

Then it could be introduced an extra way to define arcs only for tracks, 
leaving the previous definition unaltered for drawings and edges.
The pcb format would be changed only if used Arc tracks in the board.

On 07/10/2019 7:25 PM, Seth Hillbrand wrote:> I'd like to adjust how our 
arcs are handled and stored.  This is part of
> the arc tracks work package but is sufficiently tangential that I think 
> it bears checking before I implement.
>
> Problem: Arcs are stored in the pcbnew file using center, start point 
> and arc angle.  This leaves the end point of the arc subject to rounding 
> errors.  This causes problems in STEP export as well as (for the arc 
> tracks) connectivity issues as dragging requires point matching, not 
> just copper overlap.

The issue on edge STEP export (board edge not closed) is related to the 
following:

On 07/10/2019 10:52 PM, Eeli Kaikkonen wrote:> For what it's worth, in 
normal graphical arcs (especially in edge cuts) the
> two endpoints (or start and end) are usually important, the centerpoint
> isn't.

This is not true. Generally for mechanical concerns, you should start 
exactly from the centers, which are the anchors of your board.
If you start your design with mechanical constraints in mind, your board 
will not have EdgeCuts issues.