void draw_line(r32 x1, r32 y1, r32 x2, r32 y2) { vertex2f(x1, y1); vertex2f(x2, y2); }
vertex3f::operator vertex2f() const { return vertex2f(vec[0], vec[1]); }
void draw_line(r32 x1, r32 y1, r32 x2, r32 y2) { vertex2f(x1, y1); vertex2f(x2, y2); }
vertex3f::operator vertex2f() const { return vertex2f(vec[0], vec[1]); }