Particularly, I got the simulation package from here: http://simsonic.fr/. They mentioned that to create then geometry for the simulation, I need to use the script "SimSonic2DWriteMap2D" in the matlab toolbox to convert an uint8 matrix into a geometry map. However, I wonder how I can create a different geometry on my own. Do I just need to convert an image into an uint8 matrix or is other way? Thank you for reading.