Micro-Rendering for Scalable Parallel Final Gathering

1. Micro-Rendering for Scalable Parallel Final Gathering 廖仁豪

2. Outline -Abstract -Introduction -Scalable, Parallel Final Gathering -Hierarchical Point-Based Representation -Final Gathering Using Micro-Rendering -BRDF Importance Sampling -Bilateral Upsampling -Result & Discussion

3. Abstract • Micro-rendering : traverse and rasterize a hierarchical point-based scene into an importance-warped micro-buffer.

4. Introduction • Global illumination : - high quality BRDF - interactive speed CUDA、hierarchical point-base、 bilateral upsampling

5. Introduction • Final gathering : render the directly illuminated scene from every visible point and convolve with the BRDF. y0 ω0 y1 normal ω1 eye yi ωi x

6. Introduction • QSplat : - a hierarchy of bounding spheres. - leaf node -> surface element. (oriented disc & radius) - lower cost for point-based rendering.

7. Scalable, Parallel Final Gathering • Hierarchical Point-Based Representation : - random points proportional to the triangle areas. - build the hierarchy by computing a BSP of the point samples.

8. Scalable, Parallel Final Gathering • Hierarchical Point-Based Representation :

9. Scalable, Parallel Final Gathering • Hierarchical Point-Based Representation : - for deforming geometry : only update node data. (pos、normal…) - for moving object : create separate point hierarchies.

10. Scalable, Parallel Final Gathering • Final Gathering Using Micro-Rendering : Bigger than pixel Bigger than pixel Bigger than pixel Bigger than pixel Bigger than pixel Pixel-sized Pixel-sized 1-pixelsizednodes Pixel-sized Pixel-sized Pixel-sized Pixel-sized Q-Splat

11. Micro-framebuffer Q-SplatGathering

12. Micro-framebuffer Micro-depthbuffer Q-SplatGathering

13. Leaf Leaf Micro-framebuffer Micro-depthbuffer Preventingholes

14. Withray-casting Withoutray-casting Preventingholes

15. Scalable, Parallel Final Gathering • Final Gathering Using Micro-Rendering : - micro-buffer stores the index to the nearest visible node. - Reflected radiance :

16. Scalable, Parallel Final Gathering • BRDF Importance Sampling : - all the details cover a few pixels only and the rest is wasted.

17. Scalable, Parallel Final Gathering • BRDF Importance Sampling :

18. Scalable, Parallel Final Gathering • Bilateral Upsampling : - trade quality for speed. - indirect illumination is typically low-frequency. - indirect: low resolution direct: full resolution

19. Result & Discussion • Multi-bounce : - with instant radiosity - with radiosity - with photon mapping

20. Result & Discussion

21. Result & Discussion

22. Thank You !