Adding Space Warps

Next we create the Gravity space warp to tell the particles to come down. We add a box and a UDeflector space warp to tell the particles to bounce (or deflect, hence the UDeflector) off the box.

	2. Create a box to use as a ground. Drag it out in the top view, covering most of the viewport and give it a zero or negative height.
	3. Create a UDeflector (Create tab Ø Space Warps Ø Particles Only Ø UDeflector). Draw it anywhere in the top viewport, any size.
	4. In the Modify tab of the UDeflector, click Pick Object and then click the box. This tells the space warp that the box will have its deflecting properties.
	5. Select the particle system and click the Bind to Space Warp button.
	6. Click the Select by Name button, select the Gravity space warp from the dialog box, and click Bind. Then click Select by Name again, select the UDeflector space warp, and click Bind. To check whether you did this correctly, look at the modifier stack of the particles. It should look like the following graphic:

	TIP Spray uses fewer computer resources than SuperSpray. When you can get away without the extra options of SuperSpray, use Spray.

Morphing

Morphing in 3D means making a smooth transition between two different forms. The forms, or morph targets, must have the same number of vertices, because the computer interprets the morph as one object with its vertices moving around. You can combine morph targets in a key according to percentages; for example, 10% of this target with 90% of that target.

There are two types of morphing in MAX R3. The first is the compound object called Morph. This uses what is called a barycentric controller, which averages the values of the vertices of the morph targets used in a key. With the barycentric controller, if the percentages of the morph targets add up to more than 100%, the resulting key will be scaled up in size.

The second type is the Morpher modifier, new to MAX R3, which allows weighted morphing. In previous versions of MAX, a third-party plug-in was needed to get true weighted morphing. Weighted morphing is computed using vertex deltas, meaning the change in each vertex from an original state rather than an average of all states. This is necessary to create precise controls for facial animation, for example. You want to be able to get just the right eyebrow of one target and just the lips of a second target, rather than have all the eyebrows and all the lips averaged.

	TIP With Morpher, you can overshoot 100% without scaling. You might want 100% of an eyebrow raise, as well as 100% of smirked lips.

Using the Morpher Modifier

Let’s try a simple example of using the Morpher modifier. The overall procedure, itemized below, involves creating morph targets by altering the vertices of object copies in different ways, applying the morpher modifier to one of the objects, loading all the other objects as morph targets, and then animating between different target states. We start with copies of one object to ensure that we have the same number of vertices in each morph target.

1.  Reset MAX.

2.  Create a teapot and collapse to an editable mesh.

3.  Shift-drag the teapot to the side.

4.  When the dialog box appears, choose Copy and enter 5 as the number of copies, then zoom extents all.

5.  Select Teapot02 and go to the Element sub-object level. Select the teapot lid and lift it up.

6.  Leave the sub-object level, select Teapot03, and go to the Vertex sub-object level. Using soft selection, pull the vertices of the spout to the right.

7.  Leave the sub-object level, select Teapot04, and this time pull the vertices of the spout to the left.

8.  Leave the sub-object level, select Teapot05, and apply an FFD 4x4x4 modifier (Modify tab Ø More Ø FFD 4x4x4).

9.  Go to the Control Point sub-object level of the FFD. Select and move the control points of the lattice to distort Teapot05, as seen in Figure 6.13.

10.  Leave the sub-object level, select Teapot06, and apply an FFD 4x4x4 modifier.

11. Go to the Control Point sub-object level and move the control points of this lattice differently to produce a differently distorted teapot.

12.  Leave the sub-object level, select Teapot01, and zoom extents selected in the perspective viewport.

13.  Apply a Morpher modifier (Modify tab Ø More Ø Morpher).

14.  Click the Load Multiple Targets button.

FIGURE 6.13  Teapot 5 distorted with an FFD 4x4x4 lattice

15.  Select Teapots 02 through 06 from the dialog box and click Load. The teapots appear as channels in the Modify tab for Morpher.

16.  Play with the percentages of your morph target channels and watch the teapot in the viewport mutate.

17.  Turn on the Animate button, go to different frames and change the percentages of your morph target channels.

18.  Turn off the Animate button and play the animation. The teapot morphs smoothly from shape to shape.

© 2000, Frol (selection, edition, publication)