How does open inventor / coin3d enable two-sided rendering like OpenGL？

Question

Coin3D uses single-sided rendering by default like the image below：

_{(source: gitee.com)}

How does open inventor / coin3d enable two-sided rendering like OpenGL？

Answer 1

SoShapeHints is the answer, but this summary may be clearer:

• Two-sided lighting and backface culling are disabled by default.
• Two-sided lighting: enabled if not solid and ordered vertices.
  Set vertexOrdering to COUNTERCLOCKWISE (usually) or CLOCKWISE.
• Backface culling: enabled if solid and ordered vertices.
  Set shapeType to SOLID.