Page 1105 - Kitab3DsMax

Chapter 43: Simulating Physics-Based Motion with reactor
1. Open the Smashed gingerbread house.max file from the Chap 43 directory on the DVD.
This file includes a gingerbread house model created by Viewpoint Datalabs.

2. Select Animation ➪ reactor ➪ Create Objects ➪ Rigid Body Collection, and click in the Top view-
port to create the collection icon. Then click the Add button to open the Select Objects dialog
box. Click the All button, and close the dialog box with the Select button.
3. Select Animation ➪ reactor ➪ Create Objects ➪ Fracture, and click in the Top viewport to create
the Fracture icon. Click the Add button in the Properties rollout, select all the objects except for
the “Sphere01” and the “ground” objects, and click Select. In the Pieces list of the Properties roll-
out, select all the objects, enable the Break at Time option, and set the time to 30.
4. Select the “ground” object in the scene, choose Animation ➪ reactor ➪ Open Property Editor, and
enable the Unyielding option. Then select the “Sphere01” object, and set its Mass value to 60.
Finally, select all the gingerbread house objects, and set their Mass values to 20 and the Friction
value to 1.0. To be more realistic, you should set the Mass value on the smaller pieces to a smaller
value, but for this example, they can all be the same.
5. Select Animation ➪ reactor ➪ Preview Animation to open the Preview window. A dialog box
appears stating that many of the smaller pieces have a density value that likely is too high, which
you already know, so click the Continue button to close the warning window. Then press the P
button to see the animation.
The ball falls, and the house explodes into pieces.
6. Select Animation ➪ reactor ➪ Create Animation. A warning dialog box appears, reminding you
that this action cannot be undone. Click OK. Then after the animation is finished, click the Play
button to see the final results.
Figure 43.7 shows the gingerbread house as it fractures into pieces.
FIGURE 43.7
The fracture object in reactor can be used to compute realistic explosions.

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