Draw index markers on surface vertices, edges, or faces.

Input parameters:

1. Sf → Base surface.
2. Ty → Topological elements to mark.
   • 0 → Faces
   • 1 → Edges
   • 2 → Vertices
3. Bn → Optional boundary. Elements outside the boundary will be omitted.
4. Iv → Optional index intervals. Indices outside the intervals will be omitted.

Output parameters:

1. Dt → Marker dots with indices.