1. Computer Graphics and Scientific Visualization Yi-Jen Chiang (Polytechnic University)

2. Graphics and Scientific Visualization Graphics: –Surface datasets: polygonal models Scientific Visualization –Volumetric datasets: points sampling the entire volume –Can model cloud-like objects (smoke, haze…) –Can visualize the interior of datasets –Applications: Medicine, Biology, Physics, Chemistry, Mathematics

3. Graphics: Polygonal Models

4. Scientific Visualization: Volume Data

6. F(x,y,z) = x + 2y + 3z + yz 2 2 2 Scientific Visualization: Volume Data

7. Research Topics Major Challenge: –Datasets are huge for both polygonal and volumetric data –Efficiency is the key issue Our research directions –External-memory techniques – Graphics compression – Simplification/Multi-resolution

8. External-Memory Techniques Model for typical computing systems CPU Internal Memory External Memory (D disks) usually D = 1 B: # items fitting in one disk block One I/O reads/writes one block (B items) Virtual memory v.s. External-memory techniques

9. Our Research Directions External-Memory Techniques –Speed-up: 10 – 100 times faster Graphics Compression – Lossy v.s. Lossless – Connectivity v.s. Geometry compression Simplification/Multi-resolution Integration New algorithms and data structures