Lecture #8: Shadows

Shadow mapping

There are two passes:

1. Shadow map generation
2. Apply shadow maps to final image [1]

Shadow map generation

• Setup square render target (only depth buffer)
• Place a camera to light source and look to opposite direction
• Make an orthographical projection
• Render all geometry [1]

Apply shadow maps to final image

• Render final scene
• Using model space vertex position compute shadow map coordinates
• If \(Z\) from shadow map and computed \(Z\) are different - there is a shadow
• Reduce color intensity in shadow pixels [1]

“Shadow mapping” experiment

Experiment

Let’s implement it together

“Shadow mapping” experiment

What is the new knowledge?

Individual assignments

Due date: Feb 21

1. Black image
2. Color space
3. Bresenham’s line algorithm
4. Read OBJ file
5. Projections
6. Triangle rasterization
7. Z-buffer culling
8. Phong model
9. Texturing
10. Shadow mapping