The tokens in the file format match the member names of the DRAWSEGMENT object so I see how this could be confusing for arcs and circles. Changing the "start" token to "center" is not a can of worms that I want to open.
On 6/27/2017 8:45 AM, hauptmech wrote: > Just to clarify, I'm talking about the file format not the internal > implementation. > > The file_formats documentation has the old format using 'center' and > 'start' for circles and 'start' and 'end' for arcs (which go from a > start point to and end point as the terminology suggests). All good and > well. > > fp_circle has 'center' and 'end'. Makes sense. > fp_arc is defined by a center point and a start point. Different than an > arc defined by a start point and an end point. > > Arcs are a bit tricky since there are so many representations (choose 3 > of center, start, end, and angle). Mislabeling the file format doesn't > help things. > > I spent quite a while pouring over my arc generation math before > checking to see if kicad was doing something funny with it's start, end, > angle fp_arcs. Imagine my surprise to find out there was no such thing > even though the s-expressions said there was and the old file format > confirmed that that was the way kicad did things. > > I hope you can see why I thought this is an error. > > > > On 28/06/17 00:07, Wayne Stambaugh wrote: >> It's not an error. Arcs are part of the DRAWSEGMENT object which >> encapsulates line segments, arcs, etc. The start coordinate (m_start >> member) is the center point for arcs and circles. It is documented as >> such in the KiCad source. >> >> wxPoint m_Start; ///< Line start point or Circle and Arc center >> >> >> On 6/26/2017 8:19 PM, hauptmech wrote: >>> In the module s-expressions, what is the rationale for having arc center >>> labeled 'start' and having the arc starting point labeled 'end'? >>> >>> This bit me as I was writing an Allegro footprint extractor to kicad and >>> got confused why my start,end,angle arcs were not displaying correctly. >>> >>> Assuming it's an error, is there a way to fix the file format or is this >>> a permanent thing? >>> >>> >>> >>> _______________________________________________ >>> Mailing list: https://launchpad.net/~kicad-developers >>> Post to : [email protected] >>> Unsubscribe : https://launchpad.net/~kicad-developers >>> More help : https://help.launchpad.net/ListHelp >> _______________________________________________ >> Mailing list: https://launchpad.net/~kicad-developers >> Post to : [email protected] >> Unsubscribe : https://launchpad.net/~kicad-developers >> More help : https://help.launchpad.net/ListHelp > > > > _______________________________________________ > Mailing list: https://launchpad.net/~kicad-developers > Post to : [email protected] > Unsubscribe : https://launchpad.net/~kicad-developers > More help : https://help.launchpad.net/ListHelp _______________________________________________ Mailing list: https://launchpad.net/~kicad-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~kicad-developers More help : https://help.launchpad.net/ListHelp
