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SKILL code to determine if two points are connected in layout

chenyanw

Hi,

I'd like to figure out if there is a connection between two points in the layout. I know I can do that by "Connectivity->Mark Net": I define the via layers, click on one point and see if the other point is highlighted. 

But how do I write "mark net" equivalent in code? Ideally I want to take these two points as inputs, and the output would be a boolean value.

I thought I needed to use dbGetOverlaps, but I'm not sure how to define the searching bBox properly in this case as it is complicated.

Thank you very much!

  • Andrew Beckett

    Writing a complete net tracer in SKILL is quite a lot of work - I know others on the forums have done so themselves, but if I was you I'd re-use the mark net capability. What I'd probably do is:

    1. Use leMarkNet giving it a coordinate of the starting point
    2. leSaveMarkNet to save all the resulting marked shapes to a temporary cellView
    3. Use dbGetOverlaps() with a zero-area rectangle formed of the second point twice in the temporary cellView. If there are any shapes under the second point, then there's a route from a to b.
    4. leUnmarkNet to unmark it again

    Something like that anyway. A lot of work has gone into mark net and the performance of mark net, so writing your own shape tracer is almost certainly not worth the time and effort to do so (efficiently).

    Andrew.

  • chenyanw
    in reply to Andrew Beckett

    Thanks Andrew! This is very clear.

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