1. Procedural Animation Lecture 4: Basic modeling methods
Procedural Methods in 3D Computer Animation
Dr. Midori Kitagawa

2. Basic Modeling Methods
Lofting
Extrusion
Sweeping
Surface of evolution
Boolean operations

3. Lofting Originated in boat design
2D cross-sections placed in 3D space are connected by side faces to form a 3D shape.

4. Extrusion Also called projection
A copy of a 2D profile is made and translated and then the original and copied profiles are connected by side faces to form a 3D shape.

5. Sweeping
2D cross-section is swept along a 3D path to create a 3D shape.

6. Surface of revolution
2D profile is rotated around an axis to create a 3D shape.

7. Boolean operations
Boolean operation -- union (or, “u”), intersection (and, “n”), or difference (not, “-”) -- is applied to a pair of objects.
A u B
A n B
A - B
B - A

8. Boolean operations
Can produce a complicated object with a repeated used of operations.
Prone to computational errors.