ConformToPathRigPoseModifierData

Inheritance 1 ancestor · 7 siblings

• BaseRigPoseModifierData
  • ConformToPathRigPoseModifierDatacurrent
  • DynamicsChainRigPoseModifierData
  • JointOrientationRigPoseModifierData
  • JointSnapRigPoseModifilerData
  • LockRootOrientationRigPoseModifierData
  • SpringPhysicsRigPoseModifierData
  • SyncedAnimationRigPoseModifierData
  • VertexAnimationRigPoseModifierData

Class Documentation

Edit documentation

A pose modifier that makes a chain of joints trail behind the unit. A tail or a ponytail swings out when the unit moves across it, and settles back when the unit stops. Each joint of the chain turns about the world up axis only.

The chain is every joint from mStartingJointName down to mEndingJointName. The client takes the ending joint and walks up its parents until it reaches the starting joint.

What happens on each frame, for each joint of the chain in order from the start:

1. The animated direction is the direction from the joint to the next joint of the chain in the current pose.
2. The client remembers where the next joint stood in the world on the last frame. That place is moved toward the joint by a spring (mFrequency, mDampingValue) and pushed by the velocity of the unit (mVelMultiplier). The target direction is the direction from the joint to that place.
3. The joint is turned about the world up axis by the angle between the two directions, measured on the ground. The angle is at most mMaxBoneAngle, and it is multiplied by the weight of the joint.

The joints after it in the chain are computed from the pose as the earlier joints left it, so a turn at the start of the chain carries down the chain.

The weight of a joint is its weight in a mask of the animation graph. The modifier starts with the mask mDefaultMaskName. A ConformToPathEventData on a clip gives it another mask while the event is active, and the weights blend between the two masks over the blend times of the event. With OnlyActivateInTurns the weight is also multiplied by how near the joint is to a turn of the unit's path.

The path of the unit is a list of the places it has been, at most 300 of them. A place is added when the unit is more than 1 world unit from the last one, measured on the ground. A place where the path bends by more than ActivationAngle degrees is a turn.

Notes

• The modifier does nothing on the first frame. It only records where the joints stand.
• An event changes every conform to path modifier of the unit. An event cannot name one modifier.
• Ahri's base skin has eleven of them: one for each of the nine tails, one for the hair and one for the weapon arm. Their default masks have a weight of 0 on every joint, so the chains turn only while a clip has an event that gives another mask.

Properties

ActivationAngle

F32 = 0.5

Documentation Edit documentation

How much the path of the unit must bend at a place for that place to be a turn, in degrees. Read only with OnlyActivateInTurns.

ActivationDistance

F32 = 200

Documentation Edit documentation

The distance from a turn within which a joint takes the full turn, in world units, measured on the ground. Read only with OnlyActivateInTurns.

BlendDistance

F32 = 400

Documentation Edit documentation

The distance from a turn beyond which a joint does not turn, in world units. Read only with OnlyActivateInTurns.

Notes

• With a value that is not larger than ActivationDistance, there is no fade: the weight drops from 1 to 0 at ActivationDistance.

DebugVisualization

Bool = false

Documentation Edit documentation

The pose step does not read it. No use of it was identified.

ExtraJointChains

List<ExtraJointChainData> = []

Documentation Edit documentation

More chains that turn by the angles of the main chain, see ExtraJointChainData. The joint at place j of an extra chain is turned when the joint at place j of the main chain is, by the same angle changed by RightBias.

OnlyActivateInTurns

Bool = false

Documentation Edit documentation

True: a joint turns only when it is near a turn of the unit's path. The turn of the joint is multiplied by a weight that is 1 when the joint is closer than ActivationDistance to a turn, and falls in a straight line to 0 at BlendDistance. The nearest turn counts.

False, which is the default: the path is not looked at, and the chain turns whenever the unit moves.

mDampingValue

F32 = 10

Documentation Edit documentation

Slows the pull of mFrequency. A higher value makes the chain settle slower. See the formula under mFrequency.

mDefaultMaskName

Hash = "0x0"

Documentation Edit documentation

The mask the modifier uses when no event has given it another one, as a key of AnimationGraphData.mMaskDataMap. The weight of a joint in the mask is how much of the turn the joint takes. Empty, or a key that is not in the map: every joint of the chain has a weight of 1.

mEndingJointName

Hash = "0x0"

Documentation Edit documentation

The last joint of the chain, as the hash of its name. It must be below mStartingJointName in the skeleton.

Notes

• When the ending joint is not below the starting joint, the chain runs from the ending joint up to the root of the skeleton.
• The last joint has no next joint. Its target direction comes from a place the client extrapolates beyond the end of the chain.

mFrequency

F32 = 10

Documentation Edit documentation

How fast the remembered place of a joint is pulled toward the joint above it in the chain. A higher value makes the chain settle faster after the unit stops.

On each frame the place moves by velocity * dt, where

k        = 36 * mFrequency * mFrequency
velocity = k / (1 + 9 * mFrequency * mDampingValue * dt + k * dt * dt) * offset * dt
           + unit velocity * (1 - j / n) * mVelMultiplier

offset is the offset from the place to the joint, j is the place of the joint in the chain counted from 0, and n is the number of joints of the chain. Only the two ground axes are moved.

Notes

• The velocity is computed again on every frame. It is not kept from one frame to the next, so the chain does not swing past its rest place and back.

mMaxBoneAngle

F32 = 65

Documentation Edit documentation

The largest turn of one joint, in degrees. The limit is applied before the weight of the joint.

mStartingJointName

Hash = "0x0"

Documentation Edit documentation

The joint of the chain that is nearest to the root of the skeleton, as the hash of its name (FNV-1a 32 of the lowercased name).

Notes

• A name that is not a joint of the skeleton is read as the first joint of the skeleton. It is not skipped.

mVelMultiplier

F32 = -0.5

Documentation Edit documentation

How much of the velocity of the unit is added to the motion of the remembered places. A negative value pushes them against the movement of the unit, so the chain trails behind. A positive value pushes them ahead of it.

The push is full at the first joint of the chain and falls toward the end of it.

ActivationAngle

ActivationDistance

BlendDistance

DebugVisualization

ExtraJointChains

OnlyActivateInTurns

mDampingValue

mDefaultMaskName

mEndingJointName

mFrequency

mMaxBoneAngle

mStartingJointName

mVelMultiplier