How does "sized" work?

JSS

Hi everyone,

I have a question about the "sized" function.
The documentation says that it will apply a bias per edge of the polygons and return the biased layer.
I draw a triangle and size it by the script.

l1= input(1, 1)

l1.sized(1.um, 0.5.um).output(2, 1)

But I don't know why it turned out this way.

Is there an explanation of how this function works?

Thanks for your help.

tomas2004

Hello,

See here: https://www.klayout.de/doc-qt5/about/drc_ref_layer.html#h2-3079

If you don't want a "cut-off" of the corners, you have to change the mode:

l1.sized(1.um, 0.5.um, no_limit).output(2, 1)

The default mode is "square_limit".

Cheers,

Tomas

Matthias

Thanks @tomas2004 for this comment!

I should add that anisotropic sizing can have surprising effects with all-angle geometries and corner cut-off. Essentially, anisotropic sizing translates into an edge shift that is depending on the angle of the edge. Horizontal edges get the shifted by the vertical size value while vertical ones get shifted by the horizontal size value. Edges oriented otherwise receive a shift between these values.

I am not sure if the cut-off implementation makes a lot of sense for anisotropic sizing. I'd rather try to avoid that case currently by using "no_limit".

Matthias

JSS

Hi @tomas2004,

Thank you for your reply.
It answers my question perfectly.

Best regards,

JSS