1. Painterly Rendering for Animation – Barbara Meier
Presented by - Kash

2. Outline
Art based
Comparison to Other work
How it works
Results

3. Art based Don’t show everything Leave a level of abstraction
No Plastic Look

4. Art
Details abstracted by short hand brush strokes, larger brush strokes for background
Roundness of forms should be defined by brush stroke directions
Color should break boundaries of surfaces to create rhythm in the composition
Brush stroke size and texture should be varied according to the kind of surface
Effects of Light should be exagerated

5. Example

6. Comparison to Other Work
No “Shower Door” effect
No Random Noisiness
Maintain Coherence (3d particle, 2d brush strokes)
Stick brush strokes on the model and not the screen. Randomize it.
Better than texture mapped approaches (silhouettes)

7. Example

8. Example (w Brush Strokes)

9. How it Works Surface Particles placed in world space
Reference images rendered
Each particle becomes a screen space stroke

10. Algorithm create particles to represent geometry
for each frame of animation
create reference pictures using geometry, surface
attributes, and lighting
transform particles based on animation parameters
sort particles by distance from viewpoint
for each particle, starting with furthest from viewpoint
transform particle to screen space
determine brush stroke attributes from
reference pictures or particles and randomly
perturb them based on user-selected parameters
composite brush stroke into paint buffer
end (for each particle)
end (for each frame)

11. Pipeline

12. Particle Generation Compute Area of surface triangles
Randomly place particles on traingles
- Number of particles placed per triangle are proportional to the surface area

13. Reference Images Brush Strokes defined by Image Color Orientation Size
Position

14. Stroke Rendering Particle transformed to screen space
Stroke parameters from reference images
Changed according to any user specification
Brush image rendered according to stroke parameters
Grayscale brushes may be used
Grayscale textures may be used

15. Example

16. Layered Rendering Similar objects rendered together
Different objects rendered differently and in specific order
Strokes do not intrude other objects

17. Example

18. Other Samples

19. Other Samples

20. Other Samples

21. Other Samples

22. Questions