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The criteria for getting shapes from abeLayerFromCellView with a bBox argument

sbkuizlzl

Hi all.

I'm using Virtuoso IC23.1-64b.main.453 and I am trying to find the coordinates of shapes drawn with a specific layer within a bounding box.

To do this, I used abeLayerFromCellView function with the bBox argument, but the result includes the partial shape which is abutted outside the bBox.

Inside the bBox, instances are hierarchically placed and the target shapes are drawn across multiple hierarchies.

I have the following questions about it;

1. What is the criteria for the shape retrieved from abeLayerFromCellView when the bBox argument is given?

2. Is the reason why not all attached shapes are retrieved related to the hierarchy?

3. Is there a way to get only the cooridnates of shapes exactly inside the bBox with abe? 

  • Probably Andrew will chime in on points 1) and 2), but since I've observed this behaviour too I usually deal with it with dbLayerAnd processing:

    abeInit(cv ?doInterrupts t )

    foundShapes = abeLayerToCellView(abeLayerFromCellView(car(lpp) ?bbox searchBBox  ?purpose cadr(lpp) || "drawing") "y1" ?purpose "drawing" ?shapeIds t)

    abeDone()

    dummyRect = dbCreateRect(cv  "y2" searchBBox)

    targetShapes = dbLayerAnd(cv lpp foundShapes list(dummyRect))

    mapc('dbDeleteObject cons(dummyRect foundShapes)


    I am also really curious to understand the reason for the abeLayerFromCellview behaviour and implementation.

    Regards,
    Petar

  • in reply to p94todorov

    Petar,

    I believe the reason is that it is just doing a region query (similar to dbShapeQuery) which is more performant than forcing an and with the bBox too. That means that any shape that interacts with the bounding box would be included.

    I'd use abeLayerAnd to and it with the bBox - unfortunately there's no abeLayerFromPoints or similar (there's enhancement CCR 2812829 for this), so you would need to create a real temporary rectangle and then create a layer from that to do the and - this would be faster than using dbLayerAnd, especially if you don't need shapes for the result.

    Andrew

  • in reply to p94todorov

    Thank you for your reply,  and  !

    As Andrew mentioned, if the function behaves similarly to dbShapeQuery internally, the result may be somewhat understandable.

    And it's reassuring to know that there are people like Peter who have experienced the same thing as me! Thank you for your answer, and I will try the suggested method.

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