KiCad 6: Clearance Matrix

Continuing the discussion from Is there a way to define relative clearances for nets:

Hello Rene,

At this time, where are we with Clearance Matrices. Is this feature finally planned for version 6?

I couldn’t find anything significant about the fate and means of this crowdfunding campaign you mentioned more than one year ago.

Thank you.

Clearance matrixes like present in eagle have not been added to kicad. However a much more powerful rule based DRC is in (but basically without any graphical interface). See Need some guinea pigs for a rule-based DRC <<PROTOTYPE>>

Is this a V6 or a V7 feature Rene?

The team decided to implement custom DRC clearance rules without the “matrix” GUI. The idea is that in many cases, you don’t actually need different numbers in each cell of the matrix – a whole row or column, or many rows/columns, would be the same value. So, the rules system is a way of expressing that more clearly. So, if you need to say that the clearance to vias is higher than all other objects on a certain netclass, you can do that with two rules (one to set the initial clearance, and then one to make it higher for vias).

This is implemented now (in 5.99, will be 6.0). At this time we have no plans to add a “matrix” GUI in a future version.

I commented on this question in one post in Need some guinea pigs for a rule-based DRC <<PROTOTYPE>>, followed by comments by Jeff and Jon.

Thank you. Yes matrix very usually takes lots of repeats in its cells.

I must confess I didn’t get the whole of this syntax for rule-based DRC from the material quoted by Rene. However it seems very interesting, particularly to meet clearance requirements (but not only, perhaps, I don’t know).

Yes dealing with text-based s-expressions does not look like less interesting than a GUI, perhaps even more expressive.

There is not an official user manual yet (we’ll write one before 6.0 is released) so I can imagine it’s currently somewhat confusing to put together the syntax from various forum discussions and examples.

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Anyhow enough material to define selectors matching net-lists and rules for their clearances… That’s fine and I could see people in power electronics will be happy!

I have started writing the new manual. There is still much that is incomplete about it, but the section about the Custom Design rules may already be useful to people who are trying out 5.99

https://docs.kicad.org/master/en/pcbnew/pcbnew.html#custom_design_rules

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TIL, there is even an in-progress documentation for the yet to come version of KiCad under https://docs.kicad.org/master… Thank you.