X-Authentication-Warning: delorie.com: mail set sender to geda-user-bounces using -f X-Recipient: geda-user AT delorie DOT com X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.98.4 at av02.lsn.net Subject: Re: [geda-user] Primitive electrical types [WAS: Re: first attempt at bus support in gnetlist for pcb] To: geda-user AT delorie DOT com References: From: John Griessen Message-ID: <56928D6F.6080807@ecosensory.com> Date: Sun, 10 Jan 2016 10:57:19 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Icedove/38.4.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed 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 01/09/2016 06:55 AM, Peter Clifton (petercjclifton AT googlemail DOT com) [via geda-user AT delorie DOT com] wrote: > Pins and nets have different semantics regarding connection points - for one example. (One end only, vs. either end - plus > end-point to lands-on-line connections.) To me, this implies there should be different types internally, even if they are > notionally sub-classes. The subject of types got me thinking of keeping it simple. There are packaged types and layout group types and the rest is simply materials attribs of something-on-insulator. I think the easiest way forward is layers model something-on-insulator, and the something can be on one side only, and that side can be oriented up or down. With just the above, you can say: silk on top is part of the topmost layer of something-on-insulator with something on the upside. middle layers are something-on-insulator with something on the upside. silk on bottom is part of the bottommost layer of something-on-insulator with something on the bottom side. The thickness of the bottommost insulating layer might be zero -- that's OK. The silk has silk attrib material properties that give it a thickness. The above is enough to derive a complete 3D result model including curvy overlapping of painted on layers that dry, etching, photosensitive layers, etc. You could get from there to STEP later, (or never and still use STEP export heuristically)