This project requires an NVIDIA graphics card with CUDA capability! Any card with CUDA compute capability 1.1 or higher will work fine for this project.
This project uses deferred shading in OpenGL using G-Buffers. The key advantage of deferred shading is that it makes it much easier to manage your shaders, especially when you have loads of materials and lights.
- Use of G Buffers - Depth, Normal, Color, Eye space position, Shininess
- Blinn Phong lighting model
- Post process effects like bloom and toon shading
- Support for efficient rendering of multiple point lights using scissor testing in OpenGL
BLINN PHONG :
TOON SHADING:
BLOOM:
The following is a video of the deferred shading in action
The code has been tested on Visual Studio 2012/2010 and cuda 5.5 on a laptop with compute capability 1.0 as well as 3.0.
Keyboard bindings for interactivity:
| Key | Action |
|---|---|
| '1' | View depth |
| '2' | View eye space normals |
| '3' | View diffuse Color |
| '4' | View eye space positions |
| '5' | View lighting debug mode |
| '6' | View shininess |
| '7' | View toon shading |
| '8' | View bloom effect |
| '0' | Standard view |
| 'r' | Reset camera |
| 'x' | Toggle OpenGL Scissors |
Apart from this, WSADQZ and mouse can be used for movement.
There is another branch on github named "PackedGBuffer" in which I have packed my G-Buffer in a different manner.
The main difference lies in the way normals have been packed.
In the original G-buffer, there were separate G-Buffers for normals and shininess
Normals buffer:
| Component | Data |
|---|---|
| Component 1 | normal.x |
| Component 2 | normal.y |
| Component 3 | normal.z |
Shininess buffer:
| Component | Data |
|---|---|
| Component 1 | shininess |
In the packed G-Buffer, the normals G-Buffer has
| Component | Data |
|---|---|
| Component 1 | normal.x |
| Component 2 | normal.y |
| Component 3 | shininess |
For this, the third component of the normal was made on the fly using thie formula,
normal.z = sqrt(1- normal.x*normal.x - normal.y*normal.y);
| Model | Lighting | Without packed G-Buffer(fps) | With packed G-Buffer(fps) |
|---|---|---|---|
| cornell_box.obj | Blinn-Phong | 64.48 | 66.87 |
| cornell_box.obj | Bloom | 7.29 | 7.28 |
| sponza.obj | Blinn-Phong | 32.54 | 33.60 |
| sponza.obj | Bloom | 6.52 | 6.54 |
Model: Cornell_box
Blinn-Phong without bloom: 64.48 fps
With Bloom
| Kernel Size | FPS |
|---|---|
| 100 X 100 | 7.29 |
| 50 X 50 | 13.10 |
| 25 X 25 | 22.42 |
| 10 X 10 | 35.93 |
| 5 X 5 | 47.29 |
Referred this paper for toon shading, http://www.cs.rutgers.edu/~decarlo/671/readings/decaudin_1996.pdf
Referred this page for bloom(glow) effect. Implemented separable convolution technique http://http.developer.nvidia.com/GPUGems/gpugems_ch21.html