Re: gEDA-user: General Layers questions

[Steven Michalske <smichalske@xxxxxxxxx>]

On Fri, Mar 18, 2011 at 12:52 PM, John Doty <jpd@xxxxxxxxx> wrote:
>
> On Mar 18, 2011, at 1:44 PM, Martin Kupec wrote:
>
>> Generaly you are proposing that there should be a special type of
>> footpring called 'via' and it should receive extra care.
>
> Why single out "via" and "footprint" when they are merely members of an open-ended list of possible composite objects?
>
>>
>> I am ok with that, I just need to figure out how to handle mapping from
>> footprint layers to layout layers. I don't want concept of 'top',
>> 'inner', 'bottom' layer at all...that is too naive for me.
>
> A general mechanism for describing composite objects is needed.
>

I agree here, that a via and a footprint are essentially the same thing.

A via is a hole through some layers of the board and some copper bits
on those layers,  also known as a pad stack in some board packages.

A footprint is traditionally a grouping of many pad stacks and
additional layers.

No real special treatment in the descriptions of the geometry.

A group that origin is at x,y,rotation,layer

Make a generic group (sub layout) concept and your good to go.

A round via should have a rotation,  it allows easy control of the
thermals orientation.

This is not to say that a special via macro could not be setup that
makes the simplest traditional via or blind/buried vias.

These groups should not be flattened into the layout until export,
thus we loose the free rotate issue that we have today (lossy
rotations).


_______________________________________________
geda-user mailing list
geda-user@xxxxxxxxxxxxxx
http://www.seul.org/cgi-bin/mailman/listinfo/geda-user