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  3. dbGetTrueOverlaps - abutting layers

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dbGetTrueOverlaps - abutting layers

dakuang01
dakuang01 over 7 years ago

Hi,

I'd like to make a layout cellview with CB layer for pad opening and its own pad pin from original layout so I'm using dbGetTrueOverlaps function.

There is an issue I cannot get full size of CB layer by using the function. Whole CB layer is octagonal shape but it is made of two shapes which are seperated with rectangle inside and rest of it outside. The shapes are abutting each other without any gap. But I only can get rectangle CB layer by using dbGetTrueOverlaps.

Do you have any good idea I can get whole CB layer?

Thanks,

Jungyoon

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  • Andrew Beckett
    Andrew Beckett over 7 years ago

    Jungyoon,

    Your question isn't very clear. I don't know what isn't working - perhaps you could post a picture and explain more clearly what you've tried and what isn't working?

    Regards,

    Andrew.

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  • tweeksii
    tweeksii over 7 years ago

    A picture would help (doesn't have to be a screenshot, just a diagram....).

    I can tell you dbGetTrueOverlaps will find polygons (not just rectangles) if they overlap the bbox you give it, and are on the correct lpp.

    But if you want the whole CB layer anyway, maybe you should try dbLayerOr?

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  • dakuang01
    dakuang01 over 7 years ago

      

    Thank you for responding my question.

    Alright. It's hard to explain it but let me try with this diagram again. 

    The pink and skyblue shapes are all CB layer and they are abutted each other but separated shapes which are in a layout cell.

    And the VSS pin exists on the top level so CB layer and pin have different hierarchical level. I'd like to make a new cell existing CB layer and its pin on top level but I could get only the pink shape, not all the pink and skyblue shapes by using dbGetTrueOverlaps with VSS pin coordinates. Pad pin coordinates are not centered on CB now. 

    I hope this would work for you.

       

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  • Andrew Beckett
    Andrew Beckett over 7 years ago in reply to dakuang01

    You didn't explain what the region of the rectangular area provided to the dbGetTrueOverlaps was. For me, if I provide the bBox of the pink area, it finds the blue shape too. If I provide a smaller rectangle than the pink area, it doesn't return the blue shape (but it doesn't overlap in that case). 

    So it's not clear how you're trying to find the shapes. 

    Please ask precise questions as otherwise we all have to try to guess what you mean (or most likely you'll just not get an answer...)

    Regards,

    Andrew.

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  • dakuang01
    dakuang01 over 7 years ago in reply to Andrew Beckett

    I'm sorry. I will try to ask precise questions later. But I got an hint from your reply. Thank you so much. :)

    I provided VSS pin coordinates on dbGetTrueOverlaps only for getting the CB shape. That's why I couldn't get the full shape.

    I could get the full shape after making bigger size of bBox than pink area.

    Thanks, 

    Jungyoon

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