I n v e r s e    K i n e m a t i c s

Calculate IK:  Tells messiah to calculate IK (Inverse Kinematics) information for this item.  This ONLY needs to be used for the end item (end effecter) that you will assign a Goal to.  In other words, you don't turn this on for each item in the IK chain, just the end.

Anchor:  Tells messiah that this is the topmost part of an IK (Inverse Kinematics) chain and that it shouldn't calculate IK for items above it in the hierarchy, only for what's below.  You might turn this on for a character's thigh, for example, because that is the top item (root, or anchor) in a leg IK chain.

Stiffness:  This controls how resistant to movement an item is in an IK chain.  Acceptable values are 0 through 1, with 1 being the most stiff.  For example, if you have a leg, you might make the thigh "stiffer" than the calf because when you move the foot back you want the knee to bend before the thigh tilts back.  Or if you were animating a banana peeling, you would make the bottom parts of the peel "stiffer" so when you peeled it the top part would bend down first. If everything had the same stiffness, they would all bend together as one.

Minimum/Maximum:  These are IK constraints which control the range which an item can move in.  For example, you would put in rotational constraints constraints to keep an elbow from bending too far.  To use them, enter the min/max rotation values you want, and turn them on with the buttons to their left.

Strength This sets how strong each IK goal is when you have multiple goals.

Goal (pulldown list):  This is where you tell the IK chain what its controller will be.  Usually a null object is created and used for this purpose.  If you had an arm, you'd create a null object (lets call it "Hand_Goal_Left"), then select the hand in the Item list and select Hand_Goal_Left from this pulldown to be the goal.  From that point on, when you move that null object, the hand and arm will follow it.

Type (pulldown list):  There are two styles of IK in messiah: standard 2D, and telescopic. 2D works just like your elbow: it can rotate in one channel only (pitch).  Telescopic works like, well, a telescope: items can move in and out of each other (also like an extending antenna).

Direction:  Tells the joint which way to bend.  If your character's elbow bends the wrong way, select the forearm bone (or object if it's not bones) and set this switch to the opposite setting.