What you're looking for is the depth parameter, in the
PHY SET CLOTH DIMENSIONS command. This will determine in how many sections the cloth will be divided, based on the calculation (width/depth)+1) and (height/depth)+1 .
Example:
PHY SET CLOTH DIMENSIONS 1, 20, 20, 2 will have the same amount of vertices as
PHY SET CLOTH DIMENSIONS 1, 10, 10, 1. In both cases these will create a cloth with 11x11 sections and having the same amount of vertices.
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