1. Rudro Samanta Princeton University
Mesh fixup II
Rudro Samanta
Princeton University

2. Using tolerances Give vertices and edges “tolerance”
Steps in the algorithm
Vertex merging
Edge merging
Edge breaking

3. Drawbacks Spike generation User intervention required
Tolerance must be chosen carefully
How to maintain features ?
Backtracking is expensive

4. Radiosity requirements
Continuous interpolation
Well shaped
Sufficient radiator density
Sufficient receiver node density
Intersecting faces should be represented explicitly

5. Processing stages Grouper Merges geometry Removes T vertices
Maximizes coplanar faces

6. Stages continued Lsect Coplanar Pmesh Emesh
Removes face intersections by breaking planes
Coplanar
Removes overlapping coplanar faces
Pmesh
Uniformly subdivides faces
Initially squares and then traiangulation
Emesh

7. Problems Again a error tolerance is required
Authors say this is automatically computed (“scene relative tolerance”)

8. Spatial subdivision Divide space by polygon planes
Generate solidity values
Create consistent model

9. Example fixup

10. Drawbacks Missing polygons Connected parts
May generate spurious features
Connected parts
Solidity determination becomes unclear

11. Conclusion Approaches are usually straightforward
Need some user intervention in many pf the processes (usually for error bound)
Missing polygons still a mystery

12. Future work The next level (Fuzzy ?) Object recognition
Characteristic database and detection
Procedural correction