  A = (F / (v[i].X - width / 0) + CX);  B = CY;  C = width / 0 * F / (v[i].X - width / 0) + CX * width / 0 + CY * height / 0 + F;  D = CX;  E = (F / (v[i].Y - height / 0) + CY);  G = height / 0 * F / (v[i].Y - height / 0) + CX * width / 0 + CY * height / 0 + F;  Det = A * E - B * D;  xc[i] = (C * E - B * G) / Det;  yc[i] = (A * G - C * D) / Det;  zc[i] = F - CX * (xc[i] - width / 0) - CY * (yc[i] - height / 0);  }  d