kicad-developers team mailing list archive

[jp charras <jp.charras@xxxxxxxxxx>]

Le 12/01/2016 17:28, Tomasz Wlostowski a écrit :
> Hi,
> 
> When one draws a copper zone over another zone (with the same net, and
> the same layer), the two zones are automagically merged in the default
> canvas. This is sometimes not desired - at least by me (example:
> repeated layout blocks with overlapping zones). Is there a non-obvious
> reason why Kicad works this way (related to insulated copper island
> removal/connectivity/DRC algorithms)?
> 
> Cheers,
> Tom

They are merged *if* they have the same priority.
There is no really non-obvious reason.

Only at least 2 obvious reasons:

* If they are not merged, and having the same priority, how to manage
overlapping areas having for instance different and incompatible options
(thermal relief versus no thermal relief or different clearances)?
* modifying a zone is fast and very easy by adding a new area or a
cutout area, especially for complex outlines (easier than adding/moving
corners)

repeating layout blocks with overlapping zones can be made without
merging zones if these zones have their priority modified.

Note, Altium does no copy zones when copying rooms.
There is surely a reason.

I am thinking the reason is allowing overlapping zones having the same
priority can create a lot of issues.

-- 
Jean-Pierre CHARRAS