copyTriangles method Null safety
Copies the two triangles that define this.
Implementation
void copyTriangles(Triangle triangle0, Triangle triangle1) {
triangle0._point0.setFrom(_point0);
triangle0._point1.setFrom(_point1);
triangle0._point2.setFrom(_point2);
triangle1._point0.setFrom(_point0);
triangle1._point1.setFrom(_point3);
triangle1._point2.setFrom(_point2);
}