smooth_triangle
// rounded-surface FINITE (no CSG) triangle shape
smooth_triangle {
< 0, 30, 0> <0, 0.7071, -0.7071> // <Vertex1> <SurfaceNormal1>
< 40, -20, 0> <0, -0.8664, -0.5> // <Vertex2> <SurfaceNormal2>
< 0, 0, 0> <0, -0.5, -0.8664> // <Vertex3> <SurfaceNormal3>
}