Izvestiya MGTU MAMIIzvestiya MGTU MAMI2074-05302949-1428Moscow Polytechnic University6969710.17816/2074-0530-69697Solving of Tasks with Flat Triangular Element in Face Surface ModelsSuslinV Pк.т.н+7-495-223-05-23 доб. 13-92; МГТУ «МАМИ»; MSTU MAMI-MSTU MAMI200120082216516830042021Copyright © 2008, Suslin V.P.2008For the mathematical presentation of flat triangular element its parametric approximation is offered. The possibility of such approximations is shown. The area of changing parameters is determined. Actual for the CAD geometric problems with flat triangular elements such as the determination of accessories of spot to the triangle, determination of cross point direct and planes of triangle, spots projection on the plane of triangle is considered. Algorithms of their deciding and given evaluations of calculations volume are offered. Long-term use of considered methods of problems solution in the of applied software has shown theirs efficiency and high reliability.parametric approximationflat triangular elementsметоды параметрической аппроксимацииматематическое представление плоского треугольного элемента[Гилой В. Интерактивная машинная графика. М.: Мир, 1981.][Майкл Ласло. Вычислительная геометрия и компьютерная графика на С++. М.: БИНОМ, 1997.][Фокс А., Пратт М. Вычислительная геометрия. Применение в проектировании и на производстве. М.: Мир, 1982.]