CAP 211 - Interactive Design and Game Development

Chapter 42 - Creating and Animating Bipeds (part 2)


This lesson discusses crowds and delegates. Objectives important to this lesson:

  1. Crowd and delegate objects
  2. Associating a delegate with a scene object
  3. Adding behaviors to a crowd object
  4. Assigning behaviors to delegate objects

We return to the end of this chapter for a lesson on crowds. The chapter explains that we can create helper objects. This is found in the 3DS Max Help file:

The Crowd helper object, available from Create panel, Helpers, serves as the command center for setting up and solving crowd simulations. The Crowd helper object also lets you add behaviors to the scene, choose the current behavior from a list, and modify that behavior. The Delegate object acts as an agent for the motion created by the crowd object and its behaviors.

This means that the crowd object is like a control panel, and various delegate objects act as control points for the members of the crowd. You will assign behaviors to the delegates, and associate the delegates with actual objects that will act as your crowd.

The concepts will be clearer once you walk through the tutorial.

Tutorial Notes and Questions

Tutorial 1 (Rabbits in the forest):

  1. Load the indicated file. Note the Goal object and the Bunny object.
  2. Create a crowd object as instructed. Note its appearance.
    Question 1: What does the crowd object look like at this point?
  3. Create a delegate object, and place it so that the bunny is like a hood ornament on it.
    The text is not clear on the rest of this step. It should be several steps:
    1. Select the bunny, not the delegate, then click the Select and Link button.
    2. Press H for the object selection list. Note that you are selecting a parent for the bunny. Select the delegate object.
    3. Click the Select button. Region select the bunny and the delegate.
    4. Click the Select and Move button. Shift-drag the bunny-delegate combo, and use the dialog box to get five copies of the original pair. You can drag and rotate them in the scene now, or wait a bit.
  4. Follow the instructions to add an Avoid Trees behavior. Make sure you select all the tree (foliage) objects when define the behavior.
  5. Follow the instructions to add a Seek Hole behavior. Note: you have not taught either behavior to the delegates yet.
  6. behavior assignmentThe Behavior Assignments button is indicated in the graphic on the right. It takes you to the screen shown on page 994.
    What else is unclear? Create a team with buttons on the right.
    Pick a team and a behavior on the left, then add them to the list of behaviors by clicking the large vertical button with five arrows on it. (That's the New Assignment button.) I begin to grow tired of the unlabelled buttons with critical functions. Reminds me of the theory about simple tools in Larry Niven's story, The Soft Weapon.
  7. When you click the Solve button, your results will vary by your placement of the six rabbits. You may wish to place them differently and solve again.

Again, this is the only tutorial in this chapter. The process of using bipeds with delegates is described, but there is no example.