The document discusses techniques for real-time rendering of scenes with complex geometry and dynamic lights using modern GPU features. It describes using a deferred shading scheme with multiple render targets to support massive dynamic light sources. Key techniques discussed include fast shadow calculation in deferred shading, screen space ambient occlusion, shadow mapping/volumes, edge-based anti-aliasing, and screen space occlusion culling to improve performance. A multi-threading layout is proposed to map the rendering passes to GPU kernels for parallel processing of image buffers.

1. Chun-Fu Chao

2. Objective
 Utilize the Multiple Render Target and Programmable
Rendering Pipeline features on modern GPU to render
scenes with complex geometry and dynamic lights in
real-time.

3. Basic Deferred Shading scheme

4. Target Feature
 Support massive dynamic light sources
 Fast shadow calculation in deferred shading scheme
 Screen space ambient occlusion
 Shadow map / Shadow volume
 Edge detection based anti-aliasing
 Screen space occlusion culling

5. Massive dynamic light sources
 A big win of deferred shading over forward shading
 Decouple the lighting cost with the geometry complexity
http://www.youtube.com/watch?v=hBtfryQBAlk

6. Shadow
 Attenuation of light due to occlusion
 Screen space ambient occlusion

7. Shadow
 Shadow casting
 Shadow map

8. Shadow
 Shadow casting
 Shadow volume

9. Edge detection based anti-aliasing
 The hardware assisted anti-aliasing is designed for
forward rendering that works on pixel already shaded
 Enabling MultiSampling requires upsampling all the
buffers
 Huge Impact on the performance
 Detect the discontinuity(edge) of the normal and
depth
 Low pass filter across those edges.

10. Edge detection based anti-aliasing

11. Screen space occlusion culling
 Appeared in Frostbite 2
presentation from DICE in
SIGGRAPH 2009
 Occlusion culling in screen
space
 Coarse z-buffer
 Bounding boxes in Screen
space

12. Pipeline
Occlusion Rendering Anti-aliasing
culling • Lighting with • Edge detection
• Coarse z-buffer G-buffers • Low pass filter
• Remove • SSAO and
occluded Shadow
meshes mapping

13. Framework
 Developed and open-sourced by Sean M. Thomas
 Parts going to be utilized in this project
 OpenGL FBO and Cuda connection
 Model Loader

14. Multi-threading layout
 Block
 Map to a partition of the buffers
 The processing area size is related to shared memory size
 Thread
 Evenly sharing the works assigned to the block
 Gird
 Map to the whole buffer
 Kernel
 Each pass in the rendering process map to one kernel
program

15. Questions?