kicad-developers team mailing list archive

[jean-pierre charras - INPG <jean-pierre.charras@...>]

Rok Markovic a écrit :
> Hi
>
> I have started to code different way of drawing the thermal connections
> - with tracks not polygons. Because of non enthusiastic response from
> comunity and hard to solve problem with DRC, I've rethink the problem.
>
> Thermals should be done with polygons.
I agree 1000%
> Problem:
> - if we subtract holes in thermal pattern we have no way to check if
> the thermal conection is actualy connected somwhere.
>
> Proposed solution:
> 1. make polygon subtract for all pads as not in zone
Does not works.
If no pads in zone, a lot of filled areas will be missing because they 
will be detected as insulated islands and removed.
If we do not have any tracks or vias, only pads, no areas will be 
created (because no connexion detected).
> 2. Check on which points thermals will be conected to the zone.
> 3. With BOOL_OR add thermal stubs.
If you do that, you can create copper bridge between a pad and an other 
existing pad or track, because you add copper with no DRC control.

I suggest you to:
1 - creates the filled areas exactly as made currently.
2 -Using the test you made to draw thermal pads connections by segment,
find parts of thermal shape that could not be drawn using the 
connection by segment, and remove the area of thermal pads that cannot 
draw like that corresponding segment (this can be achieved by substract 
the polygon corresponding to the segment area that cannot drawn to the 
filled zone area.).
Of course one can find cases where this can fail, but you cannot creates 
DRC errors (because you remove copper, and never add copper).

> Stubs that are added can be of different shape (teardrops).
>
> If no one is working on this area and doesnt have any complaints, I will
> have a patch ready before weekend.
Currently i am not working on this.

--
Jean-Pierre CHARRAS
Maître de conférences
Directeur d'études 2ieme année.
Génie Electrique et Informatique Industrielle 2
Institut Universitaire de Technologie 1 de Grenoble
BP 67, 38402 St Martin d'Heres Cedex

Recherche :
Grenoble Image Parole Signal Automatique (GIPSA - INPG)
46, Avenue Félix Viallet
38031 Grenoble Cedex