CSci 480 Lecture Notes
(Fall) Week Seven, Wednesday; (Summer) Week Three, Thursday: Object Hierarchy (continued)
Homework.
7.3 Defining and Displaying Structures
In SPHIGS there are three steps in defining and displaying structures: 1. Open the structure.
2. Specify the output primitives and their attributes. 3. Set up a viewport to show the
structure rendered to the 2D view space.
7.4 Modeling Transformations
Matrices are used for performing model transformations: scale, rotate, or translate.
7.10 Interaction
Interaction with a 3D model via a 2D viewport is inherently problematic. Every point
in the 2D view represents an infinite number of points in the 3D model space.
"Pick correlation" refers to correlating a 3D object with a point in the 2D view.
Which object did the user mean when he clicked the mouse? Multiple objects may be
overlaid in the view. In a hierarchical structure, which level of the hierarchy?
This page established June 2, 1999; last updated October 13, 1999.