ATEC 4371.001Procedural AnimationIntroduction to Procedural Methods in 3D Computer Animation

Dr. Midori Kitagawa

In class Pay attention Take notes Learn Be ready for a pop quiz

Week 6: Modeling Assignment 4 review – The earth’s tilt Assignment 6 review Basic modeling methods Assignment 12

Basic Modeling Methods Lofting Extrusion Sweeping Surface of evolution Boolean operations

Lofting Originated in boat design 2D cross-sections placed in 3D space

are connected by side faces to form a 3D shape.

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.

Sweeping 2D cross-section is swept along a 3D

path to create a 3D shape.

Surface of revolution 2D profile is rotated around an axis to

create a 3D shape.

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 B - AA - B

Boolean operations Cookie SOP in Houdini Can produce a complicated object with

a repeated used of operations. Prone to computational errors.

Assignment 12 Create 3D models of three different

kinds of sea shells. At least one should be a univalve (a

single coiled shell), the other(s) a bivalve.

Color each model with at least two colors using Group SOPs.

Make them as realistic as you can.