Files
2026-03-04 09:37:33 +08:00

354 lines
9.3 KiB
C#

using System;
using UnityEngine;
namespace RootMotion.FinalIK
{
[Serializable]
public class IKSolverFABRIK : IKSolverHeuristic
{
public IterationDelegate OnPreIteration;
private bool[] limitedBones = new bool[0];
private Vector3[] solverLocalPositions = new Vector3[0];
protected override bool boneLengthCanBeZero => false;
public void SolveForward(Vector3 position)
{
if (!base.initiated)
{
if (!Warning.logged)
{
LogWarning("Trying to solve uninitiated FABRIK chain.");
}
}
else
{
OnPreSolve();
ForwardReach(position);
}
}
public void SolveBackward(Vector3 position)
{
if (!base.initiated)
{
if (!Warning.logged)
{
LogWarning("Trying to solve uninitiated FABRIK chain.");
}
}
else
{
BackwardReach(position);
OnPostSolve();
}
}
public override Vector3 GetIKPosition()
{
if (target != null)
{
return target.position;
}
return IKPosition;
}
protected override void OnInitiate()
{
if (firstInitiation || !Application.isPlaying)
{
IKPosition = bones[bones.Length - 1].transform.position;
}
for (int i = 0; i < bones.Length; i++)
{
bones[i].solverPosition = bones[i].transform.position;
bones[i].solverRotation = bones[i].transform.rotation;
}
limitedBones = new bool[bones.Length];
solverLocalPositions = new Vector3[bones.Length];
InitiateBones();
for (int j = 0; j < bones.Length; j++)
{
solverLocalPositions[j] = Quaternion.Inverse(GetParentSolverRotation(j)) * (bones[j].transform.position - GetParentSolverPosition(j));
}
}
protected override void OnUpdate()
{
if (IKPositionWeight <= 0f)
{
return;
}
IKPositionWeight = Mathf.Clamp(IKPositionWeight, 0f, 1f);
OnPreSolve();
if (target != null)
{
IKPosition = target.position;
}
if (XY)
{
IKPosition.z = bones[0].transform.position.z;
}
Vector3 vector = ((maxIterations > 1) ? GetSingularityOffset() : Vector3.zero);
for (int i = 0; i < maxIterations && (!(vector == Vector3.zero) || i < 1 || !(tolerance > 0f) || !(base.positionOffset < tolerance * tolerance)); i++)
{
lastLocalDirection = localDirection;
if (OnPreIteration != null)
{
OnPreIteration(i);
}
Solve(IKPosition + ((i == 0) ? vector : Vector3.zero));
}
OnPostSolve();
}
private Vector3 SolveJoint(Vector3 pos1, Vector3 pos2, float length)
{
if (XY)
{
pos1.z = pos2.z;
}
return pos2 + (pos1 - pos2).normalized * length;
}
private void OnPreSolve()
{
chainLength = 0f;
for (int i = 0; i < bones.Length; i++)
{
bones[i].solverPosition = bones[i].transform.position;
bones[i].solverRotation = bones[i].transform.rotation;
if (i < bones.Length - 1)
{
bones[i].length = (bones[i].transform.position - bones[i + 1].transform.position).magnitude;
bones[i].axis = Quaternion.Inverse(bones[i].transform.rotation) * (bones[i + 1].transform.position - bones[i].transform.position);
chainLength += bones[i].length;
}
if (useRotationLimits)
{
solverLocalPositions[i] = Quaternion.Inverse(GetParentSolverRotation(i)) * (bones[i].transform.position - GetParentSolverPosition(i));
}
}
}
private void OnPostSolve()
{
if (!useRotationLimits)
{
MapToSolverPositions();
}
else
{
MapToSolverPositionsLimited();
}
lastLocalDirection = localDirection;
}
private void Solve(Vector3 targetPosition)
{
ForwardReach(targetPosition);
BackwardReach(bones[0].transform.position);
}
private void ForwardReach(Vector3 position)
{
bones[bones.Length - 1].solverPosition = Vector3.Lerp(bones[bones.Length - 1].solverPosition, position, IKPositionWeight);
for (int i = 0; i < limitedBones.Length; i++)
{
limitedBones[i] = false;
}
for (int num = bones.Length - 2; num > -1; num--)
{
bones[num].solverPosition = SolveJoint(bones[num].solverPosition, bones[num + 1].solverPosition, bones[num].length);
LimitForward(num, num + 1);
}
LimitForward(0, 0);
}
private void SolverMove(int index, Vector3 offset)
{
for (int i = index; i < bones.Length; i++)
{
bones[i].solverPosition += offset;
}
}
private void SolverRotate(int index, Quaternion rotation, bool recursive)
{
for (int i = index; i < bones.Length; i++)
{
bones[i].solverRotation = rotation * bones[i].solverRotation;
if (!recursive)
{
break;
}
}
}
private void SolverRotateChildren(int index, Quaternion rotation)
{
for (int i = index + 1; i < bones.Length; i++)
{
bones[i].solverRotation = rotation * bones[i].solverRotation;
}
}
private void SolverMoveChildrenAroundPoint(int index, Quaternion rotation)
{
for (int i = index + 1; i < bones.Length; i++)
{
Vector3 vector = bones[i].solverPosition - bones[index].solverPosition;
bones[i].solverPosition = bones[index].solverPosition + rotation * vector;
}
}
private Quaternion GetParentSolverRotation(int index)
{
if (index > 0)
{
return bones[index - 1].solverRotation;
}
if (bones[0].transform.parent == null)
{
return Quaternion.identity;
}
return bones[0].transform.parent.rotation;
}
private Vector3 GetParentSolverPosition(int index)
{
if (index > 0)
{
return bones[index - 1].solverPosition;
}
if (bones[0].transform.parent == null)
{
return Vector3.zero;
}
return bones[0].transform.parent.position;
}
private Quaternion GetLimitedRotation(int index, Quaternion q, out bool changed)
{
changed = false;
Quaternion parentSolverRotation = GetParentSolverRotation(index);
Quaternion localRotation = Quaternion.Inverse(parentSolverRotation) * q;
Quaternion limitedLocalRotation = bones[index].rotationLimit.GetLimitedLocalRotation(localRotation, out changed);
if (!changed)
{
return q;
}
return parentSolverRotation * limitedLocalRotation;
}
private void LimitForward(int rotateBone, int limitBone)
{
if (!useRotationLimits || bones[limitBone].rotationLimit == null)
{
return;
}
Vector3 solverPosition = bones[bones.Length - 1].solverPosition;
for (int i = rotateBone; i < bones.Length - 1 && !limitedBones[i]; i++)
{
Quaternion rotation = Quaternion.FromToRotation(bones[i].solverRotation * bones[i].axis, bones[i + 1].solverPosition - bones[i].solverPosition);
SolverRotate(i, rotation, recursive: false);
}
bool changed = false;
Quaternion limitedRotation = GetLimitedRotation(limitBone, bones[limitBone].solverRotation, out changed);
if (changed)
{
if (limitBone < bones.Length - 1)
{
Quaternion rotation2 = QuaTools.FromToRotation(bones[limitBone].solverRotation, limitedRotation);
bones[limitBone].solverRotation = limitedRotation;
SolverRotateChildren(limitBone, rotation2);
SolverMoveChildrenAroundPoint(limitBone, rotation2);
Quaternion rotation3 = Quaternion.FromToRotation(bones[bones.Length - 1].solverPosition - bones[rotateBone].solverPosition, solverPosition - bones[rotateBone].solverPosition);
SolverRotate(rotateBone, rotation3, recursive: true);
SolverMoveChildrenAroundPoint(rotateBone, rotation3);
SolverMove(rotateBone, solverPosition - bones[bones.Length - 1].solverPosition);
}
else
{
bones[limitBone].solverRotation = limitedRotation;
}
}
limitedBones[limitBone] = true;
}
private void BackwardReach(Vector3 position)
{
if (useRotationLimits)
{
BackwardReachLimited(position);
}
else
{
BackwardReachUnlimited(position);
}
}
private void BackwardReachUnlimited(Vector3 position)
{
bones[0].solverPosition = position;
for (int i = 1; i < bones.Length; i++)
{
bones[i].solverPosition = SolveJoint(bones[i].solverPosition, bones[i - 1].solverPosition, bones[i - 1].length);
}
}
private void BackwardReachLimited(Vector3 position)
{
bones[0].solverPosition = position;
for (int i = 0; i < bones.Length - 1; i++)
{
Vector3 vector = SolveJoint(bones[i + 1].solverPosition, bones[i].solverPosition, bones[i].length);
Quaternion quaternion = Quaternion.FromToRotation(bones[i].solverRotation * bones[i].axis, vector - bones[i].solverPosition) * bones[i].solverRotation;
if (bones[i].rotationLimit != null)
{
bool changed = false;
quaternion = GetLimitedRotation(i, quaternion, out changed);
}
Quaternion rotation = QuaTools.FromToRotation(bones[i].solverRotation, quaternion);
bones[i].solverRotation = quaternion;
SolverRotateChildren(i, rotation);
bones[i + 1].solverPosition = bones[i].solverPosition + bones[i].solverRotation * solverLocalPositions[i + 1];
}
for (int j = 0; j < bones.Length; j++)
{
bones[j].solverRotation = Quaternion.LookRotation(bones[j].solverRotation * Vector3.forward, bones[j].solverRotation * Vector3.up);
}
}
private void MapToSolverPositions()
{
bones[0].transform.position = bones[0].solverPosition;
for (int i = 0; i < bones.Length - 1; i++)
{
if (XY)
{
bones[i].Swing2D(bones[i + 1].solverPosition);
}
else
{
bones[i].Swing(bones[i + 1].solverPosition);
}
}
}
private void MapToSolverPositionsLimited()
{
bones[0].transform.position = bones[0].solverPosition;
for (int i = 0; i < bones.Length; i++)
{
if (i < bones.Length - 1)
{
bones[i].transform.rotation = bones[i].solverRotation;
}
}
}
}
}