X-Authentication-Warning: delorie.com: mail set sender to geda-user-bounces using -f X-Recipient: geda-user AT delorie DOT com X-Cam-AntiVirus: no malware found X-Cam-ScannerInfo: http://www.cam.ac.uk/cs/email/scanner/ Message-ID: <1405875201.394.7.camel@pcjc2lap> Subject: Re: [geda-user] Octagon flag on Pad[] From: Peter Clifton To: geda-user AT delorie DOT com Date: Sun, 20 Jul 2014 17:53:21 +0100 In-Reply-To: <53C6B815.10108@sonic.net> References: <53C69EB6 DOT 6030003 AT sonic DOT net> <53C6B815 DOT 10108 AT sonic DOT net> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4-0ubuntu1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Reply-To: geda-user AT delorie DOT com Errors-To: nobody AT delorie DOT com X-Mailing-List: geda-user AT delorie DOT com X-Unsubscribes-To: listserv AT delorie DOT com Precedence: bulk On Wed, 2014-07-16 at 10:36 -0700, Dave Curtis wrote: > On 07/16/2014 02:56 AM, Peter C.J. Clifton wrote: > > On 2014-07-15 05:41, Dave Curtis wrote: > >> On 07/14/2014 09:09 PM, DJ Delorie wrote: > >>>> "octagon" flag appears to do nothing on Pad[] directives. Is this > >>>> correct? > >>> > >>> Correct. > >>> > >> Is that by plan? A friend and I are looking at "challenging footprint > >> specs" (we're easily entertained..) and I've seen a couple where an > >> interpolated octagon could be helpful. > > > > Thats a poly-curve. > > > > (As are ROUND pads, obround pads, square, .... (you get the idea). > > Well, but octagons are a RS-274X pad macro primitive, both flashed and > stroked, so they are fair game for footprint pad construction. I'd prefer to model things more generically in future, not by using classes of template objects. If we can always model a pad as a polygon / polycurve, it cuts out the multiple choice code-paths where we must select ("Is it square-ended, is it round-ended, (is it an octagon)"...) > I guess I don't understand the logic of not allowing the octagon flag on > Pad[]'s, since they are allowed on Pin[]'s. It seems to me that all the > logic should be there to draw them -- wouldn't they be handled the same > as a square aperture, even when the pad is parallel to the X/Y axes? Square pads are already broken for rotation, no need to add octagons to the list of broken geometric primitives as well! > Bonus points for allowing "HOLES" to be non-round (poly-curve) too, to > > support manufacturing slots ;) > > > > (And for footprints which use slots to pass wide tabs on a big power > > connector, for example.) > > How are footprint slots communicated to the fab house? Outline layer > paths are routed after fab, but slots would need to be routed > pre-plating. Would another mechanical layer be added that contains slot > routing information? And do you communicate slot outlines or a toolpath > and tool diamater? Its been a while since I was involved on a board which used them, but IIRC, we manually pasted the relevant outline contours onto an unused layer, which the fab used as a pre-plating process route-layer. I think the communicated data was interpreted much as outlines usually are.. they cut so the edge of the cutter follows along the centreline of your layer geometry. A more robust communication would just be the contour, with no width - but gerber doesn't really do that. (I guess in theory, the outline trace could be made with a 0-width aperture, but PCB doesn't natively support this at the moment). -- Peter Clifton Clifton Electronics