1. A simulation method comprising: dividing a material surface into finite computational elements; and calculating a deposition rate or etching rate at each of the computational elements to simulate a feature profile of the material surface, the calculating including calculating an indirect effect of a first computational element on the deposition rate or etching rate of a second computational element, the calculating the indirect effect including: correcting a surface profile at the first computational element on the basis of a surface structure around the first computational element; and calculating the indirect effect on the basis of the corrected surface profile at the first computational element.