kicad-developers team mailing list archive

[Wayne Stambaugh <stambaughw@xxxxxxxxx>]

On 8/22/2017 5:33 PM, Thomas Langås wrote:
> On Tue, Aug 22, 2017 at 9:36 PM, Wayne Stambaugh <stambaughw@xxxxxxxxx> wrote:
>> I'm not opposed to this change.  However, there are two schools of
>> thought when it comes to board layout: strict layout constraints and no
>> layout constraints.  I tend to lean towards the latter but I've been
>> doing this for 30 years so I am painfully aware of the pitfalls of no
>> layout constraints and have a pretty good idea of what not to do.
>> Should we choose to loosen the layout constraints for blind/buried vias,
>> then we should be prepared for a serious tongue lashing the first time
>> someone violates their board vendor's manufacturing limitations and ends
>> up with a bunch of useless and likely expensive boards.  Maybe at some
>> point in the future we will have a complete constraint system that can
>> cover all possibilities but until then we have to walk that fine line
>> between power users and beginners.
> 
> 
> Is there a good reason why not to build this by rulesets, and allow
> people to define
> their own rulesets within KiCAD.  You can have a sensible default rule
> that covers
> the 80-90%, and allow the people who know more about this and what they need
> just remove the default rule and add their own advanced rules?

I believe this would require some major refactoring of the Pcbnew
internals to handle constraints.  The current design is rather ad-hoc
and would be difficult to extend.

> 
> Of course, this would imply that without any rules at all, it's just
> willy nilly and
> everything allowed.  But isn't that the way design rules should be?  If you want
> to try ice skating down a mountain, it might not be smart, but it's your own
> choice  ;-)
> 
>