2. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting

5. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting

6. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting  Check for intersection with an object  Find the closest intersection

7. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting  Just works  Simple, well understood algorithm  No input data tweaking  Delivers…  Accurate visual simulation  Physically correct results  Useful not only for rendering…  Collision detection, object picking, measuring, etc.  Becoming fast  Moore’s law  Algorithms (parallelism)  Real-time visual effects never possible before

8. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting  Three-dimensional integral  Split dimensions  Solve numerically  Solve analytically

9. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting  Observation  is piecewise constant  Analytic solution  Ray in space  Reformulate integral 

10. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting  Numerical solution A

11. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting

12. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting  Numerical solution  Piece-wise linear surface approximation  Need to clamp when

13. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting

14. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting

15. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting

16. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting

17. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting

18. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting

19. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting

20. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting

21. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting

22. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting 1g2a molecule

23. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting  Close match to MSMS

24. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting  Varying accuracy  “Bad” triangulations  Clamping

25. Iliyan Georgiev Measuring Properties of Molecular Surfaces Using Ray Casting  Performance  Just fast  Can trace millions of rays/sec  Presented results – only 40,000 rays!  Byproduct of visualization  Triangulation is the bottleneck  Completely generic approach  Triangulation can be avoided altogether!  Different surface representations  Analytic SES, skin surfaces, arbitrary implicits, …  Seamless integration in BALLView  i.e. clipping regions