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Chapter 3
3. Specifying the Appearance of Geometries
The geometry and appearance of a shape are independent of one another. The
appearance of a shape is the two-dimensional texture, such as the rind of an orange, that
is mapped onto a geometry.
This chapter describes how to specify the appearance of a geometry in the following
sections::
•“csContext Overview” on page 35.
•“Changing the Context” on page 39.
•“Using csAppearance” on page 40.
•“Applying Textures to Geometries” on page 42.
•“Material Settings” on page 51.
•“Shade Model Settings” on page 53.
•“Transparency Settings” on page 53.
•“Making the Screen One Color” on page 39.
csContext Overview
A csContext object maintains the OpenGL graphics state for a scene graph and therefore
contains all the default appearance values necessary to render a shape.
Appearance values, such as material and texture, can be specified per shape using
csAppearance. If csAppearance fields are not set, the shape inherits the default
appearance values set in csContext. For optimal performance, set as few csAppearance
object fields as possible by setting the global defaults in csContext to values that satisfy
the majority of geometries in a scene graph. This practice minimizes state changes while
rendering.
