How to Create a Thousand Lights Stephen Smithbower Computer Science Undergraduate
Lighting is an Artistic Tool - Creates mood and atmosphere - Colours can be calming - Useful for both realism and surrealism or abrasive
Author: Brooks 3drender.com
Author: Dan 3drender.com
Author: Hans 3drender.com
Author: Michal 3drender.com
Lighting is Complex And is therefore slow to render.. - Each frame of video = 1/24th of a second - Each frame takes on average 6 hours to render Some frames take up to 90 hours! Pixar Authorship: Disney Pixar Studios
Real-Time Is a Bit More Restrictive For smooth movement, the entire frame must be rendered in milliseconds (1/60th of a second, or 60 frames per second)
Don’t Be Pixar Aesthetically plausible, not physically accurate
The Graphics Processing Unit (GPU) - Excels at parallel tasks - Much more processing power than the CPU - Built specifically for real-time graphics
Forward Shading 11 Yellow Light 11 Blue Light
Forward Shading 11 Yellow Light Render this, GPU! 1 Draw Call
Forward Shading 11 Blue Light Render this, GPU! 2 Draw Calls
Forward Shading 11 Yellow Light Render this, GPU! 3 Draw Calls
Forward Shading 11 Blue Light Render this, GPU! 4 Draw Calls
So What’s the Problem? Bottleneck !
You’ve got a relay team.. GPU
Bottleneck! CPU
Forward Rendering Scene Complexity Most Video Games In Here
New Approach - Don’t send redundant data - Don’t worry about what is not in view - Decouple Light and Geometry data Current Complexity: # Objects x # Lights Desired Complexity: # Objects + # Lights
Light Pre-Pass Step 1: Encode Visible Geometry into a Texture Depth Normals 5
Light Pre-Pass Step 2: Draw Lights as Spheres
Light Pre-Pass Step 3: Render Scene Again - Modulate Lighting x=
Comparison of Rendering Scene Complexity
Rendered on a 2.4ghz dual-core processor, Geforce 8600gts video card About $500 total, at time of purchase Questions?
Acknowledgements Dr. Ramon Lawrence Computer Science Department