subroutine i21tri(bpe, pe, bpn, pn, add, irect, x, nb_nc, nb_ec, xyzm, i_add, nsv, i_amax, xmax, ymax, zmax, maxsiz, i_stok, i_mem, nb_n_b, cand_n, cand_e, nsn, noint, tzinf, maxbox, minbox, j_stok, msr, xm0, multimp, itab, gap, gap_s, igap, gapmin, gapmax, marge, depth, drad, id, titr, ix1, ix2, ix3, ix4, nsvg, x1, x2, x3, x4, y1, y2, y3, y4, z1, z2, z3, z4, xi, yi, zi, x0, y0, z0, stif, nx1, ny1, nz1, nx2, ny2, nz2, nx3, ny3, nz3, nx4, ny4, nz4, p1, p2, p3, p4, lb1, lb2, lb3, lb4, lc1, lc2, lc3, lc4, pene, prov_n, prov_e, n11, n21, n31, dgapload)