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How to code Segment Over Voids

Laurenchi

Hi,

I understand there's build-in function in Display->Segment Over Voids available, but it will process all nets and take a long time to complete, in addition, it can not filter out the voids under BGA, which makes the whole SOV reports is too large and not exactly what I want.

So I tried to write a script to do the same thing, I used the loop to get each bBox of segments of one net, and use axlSetFindFilter and axlSingleSelectBox to collect all shapesegs in the area and filter out the objects which is not in reference plane. However, this script is not accurate enough and take longer time to complete.

Due to the characteristic of bBox, the reports shows all elements in the bBox area which might not really underneath the nets, it's just close to the net. 

For example, the report will include the red circle on the right (keepout) which is not really underneath the net.

 

It also takes longer time to complete than the build-in SOV function when I'd like to process a bunch of net (~100 nets), even will hang forever.

Does anyone have idea to code SOV in another way? Any advice is appreciated.

Thanks in advance.

 

  • B Bruekers

    If you only want to select only items underneath the cline seg/cline then you first need to convert it to a polygon. Set the find filter to shapes and pass the clines polygons to axlAddSelectPoly() to do a selection.

    Since you can pass multiple polygons to this selection function it is wise to first merge all clines polygons with axlPolyOperation(  'OR) and do the selection only once.

    Then create a list of polygons of these selected shapes, merge them again with axlPolyOperation(  'OR) . Go over all cline polygons and get the overlap axlPolyOperation(  'AND). The resulting polygon is the actual overlap.

  • Laurenchi
    in reply to B Bruekers

    Thank you so much for your reply, it's really helpful!! I will study the method you provided and try to modify my code. :)

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