Creating Reactions in a Hand

Introducing the Reaction Manager

Animating Crowds

 

Autodesk 3ds Max Tutorials > Animation Tutorials > Introducing the Reaction Manager > 

Refining the Reactions

Now that you have defined the basic reactions that uniformly curl and uncurl the fingers and thumb, you can use Reaction Manager to add some subtlety to the finger movement.

Set up the lesson:

• Open the file hand_reactions03.max from your \tutorials\reaction_manager directory, or continue from the previous lesson.

  If the Reaction Manager dialog is not open, choose Animation menu > Reaction Manager to display it.

Adjust the finger curling:

Real finger joints don't rotate uniformly; to simulate that movement you will adjust the reaction curves on a bone-by-bone basis.

1. On the Reaction Manager dialog in the Reactions list, choose BN_Pointer01 / Y Rotation.

   

   A single curve appears in the graph section of the Reaction Manager dialog, representing the reaction states for this Reaction controller. You will edit this curve to add some variety to the movement of the different joints.

2. Click one endpoint of the curve to select it, and then CTRL+click the other endpoint so that both are selected. Right-click either endpoint and then choose Bezier-Corner from the menu.

   

3. Adjust the handles of the curves, so that the curve eases into the endpoints, as shown in the following illustration.

   

4. Right-click the middle point, which represents the original state, and then choose Bezier-Smooth from the menu. Adjust the handles so that the curve flows smoothly through the point, as shown in the following illustration.

   

   TipYou can also drag the point within the graph to further refine the curve.

   Next, you 'll adjust the other fingers.

5. In Reaction Manager > Reactions list, click BN_pointer02 / Y Rotation and then CTRL+click BN_pointer03 / Y Rotation so that both are highlighted. Adjust the curves in the graph so that each has its own distinctive shape.

   

6. In the Perspective viewport, select the CNT_HAND object and move the Pointer slider back and forth. Compare the way the bones curl when moving the Pointer slider to the way the bones curl when moving the Middle slider. This slight variation in speed between fingers adds a subtle bit of realism that keeps your animation from looking too mechanical.

   Repeat the steps in this procedure for the remaining fingers.

   TipTo select multiple endpoints or midpoints, drag a region over all of them in the graph.

   

   

Set up the splay:

In this procedure, you'll define one more reaction controller: the Splay attribute.

1. Open the file hand_reactions04.max from your \tutorials\reaction_manager directory, or continue from the previous section.
2. On the Reaction Manager dialog, click the Add Master button. Select the CNT_HAND object in the viewport, and choose Modified Object > Attribute Holder > Custom_Attributes > Hand Splay from the menu.
3. Press H to display the Select From Scene dialog. Highlight the hand’s base joints (BN_Thumb01, BN_Pointer01, BN_Middle01, BN_Ring01, and BN_Pinky01) in the list, then click OK to select them as a group.
4. On the Reaction Manager dialog, with the bones still selected, click the Add Selected button. Navigate the menus to choose Transform > Rotation > Z Rotation.
5. Click the Create Mode button to turn it on.
6. Select CNT_HAND in the viewport. On the Modify panel > Attribute Holder modifier > Custom Attributes rollout, drag the Hand Splay slider all the way to the right.

   

7. Rotate each finger's base joint around its local Z axis so that the fingers are spread out, as shown in the following illustration.

   

   Warning Make sure the Reference Coordinate System is set to Local.
8. On the Reaction Manager dialog, click the Create State button.
9. Select CNT_HAND in the viewport, and drag the Hand Splay slider all the way to the left.

   

10. Rotate each finger's base joint around its local Z axis so that the fingers are close together.

    

11. On the Reaction Manager dialog, click the Create State button.
12. Click the Create Mode button to turn it off.

You've now captured the movement of individual digits on the hand, making it easy to animate the motion of the fingers and thumb. Try selecting CNT_HAND and sliding each of the sliders to see their effect, and how they work with each other. Compare your results to those in the finished file hand_reactions05.max.

Experiment with keyframing the locations of the sliders to create different finger animations.