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KLayout Main Sources
http://www.klayout.org
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polygon size #1580

Open ZZG-Z opened 6 months ago

ZZG-Z commented 6 months ago

Hi, when the size of layout over 2500um will generate confusion polygon. So, does the Klayout has some default setting that limits the size of whole layout?

klayoutmatthias commented 6 months ago

There is an inherent limitation in GDS2 because it uses 32 bit coordinates which are integer multiples of the database unit.

Depending on the DBU setting you can create geometry that covers -2e9 .. 2e9 DBU. So if you set your DBU to 1e-6 (µm) this may explain why you do see this behavior. A typical DBU today is maybe 0.1 nm. From the physical perspective a lower value does not make much sense as this is the atomic dimension. With this value you can theoretically cover about -200mm to 200mm. In reality, -100mm to 100mm is a safe area.

You can build KLayout with 64bit coordinate support. That will enable a virtually unlimited area, but double the memory footprint and is not compatible with GDS2. Only OASIS will work then.

Matthias