Chapter 3. Parameters, Textures, and Expressions

This chapter continues to present Cg concepts through a series of simple vertex and fragment programs. The chapter has the following three sections:

  • “Parameters” explains how Cg programs handle parameters.

  • “Texture Samplers” explains how fragment programs access textures.

  • “Math Expressions” shows how math expressions compute new vertex and fragment values.

Parameters

The C2E1v_green and C2E2f_passthrough examples from Chapter 2 are very basic. We will now broaden these examples to introduce additional parameters.

Uniform Parameters

C2E1v_green (see page 38 in Chapter 2) always assigns green for the vertex color. If you rename the C2E1v_green program and change the line that assigns the value of OUT.color ...

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