Table of Contents
Chapter Objectives. After reading this chapter, you'll be able to do the following:
Describe the different types of sensors that can be used in a scene graph and give possible uses for each type
Understand how sensors are scheduled in the delay queue and the timer queue and when they are processed
Write callback functions for use by data and timer sensors
Set the priority of a delay-queue sensor
This chapter describes how to add sensors to the scene graph. A sensor is an Inventor object that watches for various types of events and invokes a user-supplied callback function when these events occur. Sensors fall into two general categories: data sensors, which respond to changes in the data contained in a node's fields, in a node's children, or in a path; and timer sensors, which respond to certain scheduling conditions.