Can you create a unique signature from GDS polygon shapes?

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majd229

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Can you create a unique signature from a GDS polygon shapes?

Hello,

My company uses Calibre for layout manipulation.

I'm exploring an idea where we can convert a DRC violation markers database into a layout/GDS (done), then create a unique signature from that particular rule.

For example, run DRC, and it fails on one rule, ruleX.

We take ruleX violation markers and convert it to GDS polygons (done).

Then, I want to get a unique signature on that particular GDS/rule markers.

You would say md5sum, sure, but the problem is that if in one run, the violation was one big rectangle, but in another run in a differen calibre version or for a number of factors, the violation was split into 2 small rectangles that make that same big rectangle from the first run. Although the violation shape is the same, it is now made of 2 rectangles, which will alter the md5sum.

Is there a way in Calibre to get rid of that issue, for example a way to combine any small shapes touching each other into 1 big shape, and if there are 2 shapes overlapping exactly, then merge them into 1 shape?

Thanks,
Majd
 

Re: Can you create a unique signature from a GDS polygon shapes?

Every layout tool I have seen has a "merge selected" command
that will combine abutting or overlaping polygons and paths
on the same layer into single superset shapes.

You might like to copy error shapes to a working layer, merge,
delete the precursor shapes and change layer of the merged
back to error-layer, for ease of selecting cleanly just what
you want.

But I do not use Caliber.
 

Re: Can you create a unique signature from a GDS polygon shapes?


I am almost sure Calibre is not able to do anything like what you want automatically. You can do XOR compare, which would flag that that 1 big shape is equivalent to the 2 overlapping ones, but it would not combine them automatically for you, it would only flag them.

- - - Updated - - -


The merge functionality is there. But the problem is that the OP wants to automate the merge of 2 arbitrarily selected shapes. I am not sure that can be done.
 

Re: Can you create a unique signature from a GDS polygon shapes?




Can you elaborate? I wasn't able to find anything about "merge" in the reference manual, not even remotely. Thanks
 

Re: Can you create a unique signature from a GDS polygon shapes?

Can you elaborate? I wasn't able to find anything about "merge" in the reference manual, not even remotely. Thanks

I believe the command is layout and the option is merge.
 

Re: Can you create a unique signature from a GDS polygon shapes?

I see. That actually merges multiple layouts.

Actually, I use layout filemerge to merge multiple rule GDS into 1, but i guess that doesnt merge the shapes.

- - - Updated - - -

You are right. I have 2 arbitrary shapes in 1 layout.
Any remedy to this issue?
 

Re: Can you create a unique signature from a GDS polygon shapes?

DRC as I have observed it, always does a merge-all layer by
layer before performing any of the checks for spacing or extent.
I have often seen this use a "destination layer" so as not to
mung the original database.

Perhaps within the Caliber engine this is what goes on as well,
in which case maybe a Caliber script is your ticket (like, "run
DRC on the DRC and save it out").
 

Re: Can you create a unique signature from a GDS polygon shapes?

Okay, lets say the shapes are the same and cells are the same 2 different gds. How can I get a unique signature for shapes+cells and ignore any text labes in the GDS? md5sum wont work for the GDS obviously since there is probably different binary data for the timestamp etc.
 

Re: Can you create a unique signature from a GDS polygon shapes?


I think you should consider building your own tool. There is freely available code for GDS parsing, so that part is done. You just have to script your intended functionality.
 

Re: Can you create a unique signature from a GDS polygon shapes?

Mentor has implemented a utility called "checksum_util" that does exactly what you want.
It should be available in standard Mentor software installation path.

Their algorithm is described in this paper:

https://ieeexplore.ieee.org/document/7105901/
 

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