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  3. Shape - line intersections?

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Shape - line intersections?

augustot
augustot over 12 years ago

Hello everybody,

    I am a newbee here, and I would like to learn which is the best way to find the intersections (if any) between a shape in my layout (e.g. a rectangle) and an ideal line using SKILL (6). I need then to reiterate the procedure through all the objects in my layout.

It would be even better if the "ideal line" would be a selected ruler segment.

Do you have any hint?

Thanks a lot in advance!

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  • Andrew Beckett
    Andrew Beckett over 12 years ago

    I don't think I entirely understand what you mean. I have some code to find any shape which a line is crossing - I have solution 11024326 which provides this code (this is a standard feature in IC615, but the way it is implemented may still be useful). Maybe that's what you want? I don't know what you mean by "find the intersections" - what does the intersection of a shape with a line actually mean? Do you want to find the points on the edges where the intersection occurs? Whether the shape is intersected or not? Chop the polygons into pieces based on the intersection? 

    Explaining your purpose would help clarify that.

    Kind Regards,

    Andrew.

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  • augustot
    augustot over 12 years ago

    Dear Andrew,

       many thanks for your prompt reply.

    I am sorry for my bad description of the problem. My goal is finding the (x y) coordinates of all the shapes intersecting a ruler from all (or some) layers. Imagine you want to create the equivalent cross section of your biased layout...

    I played a little with dbGetTrueOverlaps(), but I didn't get the desired result when the ruler intersected a polygon or a path.

    Now I am experimenting with dbLayerAnd() and the results are pretty good.

    I create a new rectangle starting from the ruler bBox, then I apply dbLayerAnd() between all the objects I need and this new rectangle, and finally I use the bBox coordinates of these new objects for my my needs...

     It is likely there is a faster and more elegant solution... but this is my very first skill code :)

    Now I have to learn two basic things:

    1) is it possible to select shapes inside an instance without flattening it?

    2) how can I select shapes from a single layer?

    I'll keep you posted with my progress ;)

    Thanks again for your help. I am finding all your replies very helpful!

    Best regards,

    Augusto

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  • Andrew Beckett
    Andrew Beckett over 12 years ago

    Augusto,

    The code I pointed you to is close to what you want, except that only deals with top level shapes. You could extend the dbGetOverlaps call in the code to return things from down in the hierarchy, and then transform the coordinates being compared to the top level coordinate system by using dbTransformPoint and dbGetHierPathTransform.

    dbGetOverlap can specify the layer-purpose that is being used too.

    Sorry for not giving much detail - most of the info is in the code I already sent, and I'm rather short of time at the moment as I'm out of the office.

    Andrew.

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  • augustot
    augustot over 12 years ago
    Hello Andrew,

    sorry for my late reply, but I have been quite busy in the last days.

    Anyhow, many thanks for yours suggestions. I have been able to write some decent code that I am improving day after day as my knowledge of Skill advances.
    So far I asked my "users" to simply flatten their layout before running my code, but I am going to try to follow your suggestions to get the coordinates of objects inside instances...

    Thanks again for your help,
    Augusto
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