1. DPL2/10/2016 CS 551/651: Final Review David Luebke cs551dl@cs.virginia.eduhttp://www.cs.virginia.edu/~cs551dl

2. DPL2/10/2016 Administrivia Exercise 2 sign-up sheet Exercise 2 sign-up sheet –3-5 PM, May 4-11 Course evaluations Course evaluations Assignments graded by Monday, May 10 Assignments graded by Monday, May 10

3. DPL2/10/2016 Final Exam Format: in-class, closed-book, closed-note, closed-computer exam Format: in-class, closed-book, closed-note, closed-computer exam Length: 1-2 hours expected length Length: 1-2 hours expected length Topics: All lectures, all reading Topics: All lectures, all reading

4. DPL2/10/2016 Realism Global vs. local illumination models Global vs. local illumination models Ray tracing Ray tracing –Principles & limitations –Optimizations –Advanced techniques

5. DPL2/10/2016 Realism Antialiasing: theory & practice Antialiasing: theory & practice –Frequency domain, Nyquist limit, etc. –Convolution, filters, etc. –Sampling strategies –Antialiasing & texture mapping

6. DPL2/10/2016 Realism Radiosity Radiosity –Principles & limitations –Progressive radiosity –Computing form factors

7. DPL2/10/2016 Speed Visibility Visibility –View-frustum culling –Cells & portals Airey: ray-casting Airey: ray-casting Teller: linear programming line-of-sign calculations Teller: linear programming line-of-sign calculations Luebke (pfPortals): depth-first adjacency graph traversal using cull boxes Luebke (pfPortals): depth-first adjacency graph traversal using cull boxes

8. DPL2/10/2016 Speed Visibility continued Visibility continued –General occlusion culling Hierarchical Z-Buffer: coherence in image space, object space, and time Hierarchical Z-Buffer: coherence in image space, object space, and time Hierarchical Occlusion Maps: depth vs. overlap, single-pass occluder selection, using texture hardware to accelerate HOM Hierarchical Occlusion Maps: depth vs. overlap, single-pass occluder selection, using texture hardware to accelerate HOM

9. DPL2/10/2016 Speed Level of detail mechanisms Level of detail mechanisms –Sampling –Adaptive subdivision –Decimation –Vertex merging

10. DPL2/10/2016 Speed LOD criteria LOD criteria –Geometric vs. perceptual –Vertex clustering: importance ranking Curvature Curvature Edge length Edge length –Decimation: distance from plane, distance from edge –Quadric Error Metric: squared distance from all supporting planes

11. DPL2/10/2016 Speed LOD algorithms LOD algorithms –Vertex clustering (Rossignac, Low) –Decimation (Schroeder) –Quadric error metrics (Garland)

12. DPL2/10/2016 Speed Choosing LODs Choosing LODs –Simple metrics (distance, screen size) –"Knapsack” approach Cost (time, polygons) Cost (time, polygons) Benefit (lots of possible criteria) Benefit (lots of possible criteria)

13. DPL2/10/2016 Speed Dynamic LOD Dynamic LOD –Idea: don’t build LODs in preprocess, build data structure & extract LODs –Mechanism: reversible vertex clustering/edge collapsing Structures: vertex tree, active triangle list Structures: vertex tree, active triangle list Store tris, subtris with nodes Store tris, subtris with nodes –Static vs. dynamic LOD: pros & cons –View-dependent LOD: pros & cons

14. DPL2/10/2016 Speed Dynamic LOD continued Dynamic LOD continued –View-dependent LOD criteria Vertex cluster size Vertex cluster size Silhouette preservation Silhouette preservation Triangle budget Triangle budget –Optimizations: temporal coherence, asynchronous parallelization

15. DPL2/10/2016 Topics Work we’ve sampled in more detail: Work we’ve sampled in more detail: –Debevec: modeling & rendering architecture from photographs –Zhang: Hierarchical Occlusion Maps –Luebke: View-dependent polygonal simplification –Raskar: Image-precision silhouette edges