MORE ON THE LEG IK
First, we'll need to assign the reactor controllers. Select the Pivot_heel point. Assign a list controller to its Z rotation track. Assign a reactor controller to the track labeled 'Available'. When prompted to select the React to object, select the Foot Roll attribute in the FootControl object. Leave the reactor's properites dialogue box open. Repeat the above operation for the Pivot_ankle and Rotator_footroll objects. Once you have the three reactor dialogue boxes open, do the following.
If you stand up and walk a few steps (please do if you can), you'll notice that the walk cycle uses different pivots at different stages of each step. You start using the ankle, then the heel, then the ball, and then the toes. This requires leg setups to have several pivot points that work independently, but also as a group. This makes crucial to know not only where to place pivots, but how to link them together so that they'll work as expected. Take some time watching yourself in the mirror doing several actions, and watch carefully how your legs and feet move and act during each motion. You'll notice that this is perharps one of the most complicated areas of motion.
Animate the FootRoll attribute so that at frame 0, it has a value of -5. At frame 10, it's value should be 0. At frame 20, a value of 5, and at frame 30 a value of 10. Go back to frame 0.
Go into the reactor dialogue for the Pivot_heel object. One reaction has already been created. Rename it to Pre Roll. Press the Set Reaction Value button, and adjust the state spinner. As you adjust it, you'll see the foot roll on its heel. Adjust it until you get a pre-roll pose you like. Then, move the time slider to frame 10 (when the Foot Roll has a value of 0). Create a new reaction, and name it Neutral. Click on the Set Reaction Value button, and enter a value of 0 in the State spinner. This will return the foot to its neutral state. You can close
this dialogue box if you wish.
So far, you've already created the pre-roll motion. Move the timeslider and see your foot rotate on its heel automatically. Regoice yourself... (just kidding here...). Let's continue.
At frame 10 (you should still be there), go into the Pivot_ankle reactor controller dialogue box. Re-name the current reaction to Neutral. Click on the Set Reaction Value button, and enter a value of 0 in the State spinner. Now, move to frame
20. Create a new reaction named Mid Roll. Click on the Set Reaction Value button, and start adjusting the State spinner. You'll see your foot roll on its ball. When you get the angle you like, close the dialogue box. Go into the last reactor controller dialogue box, rename the current reaction to Mid Roll, click on the Set Reactions Value button, and enter a value of 0 in the State spinner. Move to frame 30, and create a new reaction. Name it Full Roll. Click on the Set Reaction Value button, and start asjusting the State spinner. You'll see the foot roll on its toes. Adjust as desired. Close the dialogue box.
Go back to frame 0 and move the time slider (alternatively, adjust the Foot Roll spinner on the FootControl object interactively). Watch your character do a complete foot roll. This is a fully automated foot roll.
As last minute touchups, select again the three nodes involved (one by one), go to their rotation tracks, and set as active the bezier float contoller in the list controller of their Z rotation track. This will allow you to animate the objects interactively while keeping the automated controls active underneath. We'll do that constantly.
Ok. We got the first control all set up. Let's get going with the third. ???, you might say. What about the third. We'll leave that one for the last. The third control is the Swivel Angle custom attribute. This one is set up just the same way as the arm. Since we've already done this, I won't go into details. Just wire this attribute to the IKchain_ankle's swivel angle. You're done (don't forget the degtorad expression!!!).
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