% positivecharge.mp % L. Nobre G. % 2004 input featpost3Dplus2D; beginfig(1); numeric size, num, i, j, coos[]; string comm, bray; color fro, tip;; size = 1.5; num = 70; bray = "0.05"; draw rp(black)--rp((size,0,0))--rp((size,size,0))--rp((0,size,0))--cycle; for i=1 upto num: for j=1 upto 6: coos[j] := uniformdeviate(size); endfor; fro := (coos1,coos2,coos3); tip := (coos4,coos5,coos6); comm := "positivecharge(true," & cstr(fro) & "," & bray & ");"; getready( comm, fro ); comm := "positivecharge(false," & cstr(tip) & "," & bray & ");"; getready( comm, tip ); endfor; doitnow; endfig; end.