Files
2026-03-04 10:03:45 +08:00

234 lines
5.5 KiB
C#

using System;
using UnityEngine;
namespace RootMotion.FinalIK
{
[Serializable]
public class IKSolverHeuristic : IKSolver
{
public Transform target;
public float tolerance;
public int maxIterations = 4;
public bool useRotationLimits = true;
public bool XY;
public Bone[] bones = new Bone[0];
protected Vector3 lastLocalDirection;
protected float chainLength;
protected virtual int minBones => 2;
protected virtual bool boneLengthCanBeZero => true;
protected virtual bool allowCommonParent => false;
protected virtual Vector3 localDirection => bones[0].transform.InverseTransformDirection(bones[bones.Length - 1].transform.position - bones[0].transform.position);
protected float positionOffset => Vector3.SqrMagnitude(localDirection - lastLocalDirection);
public bool SetChain(Transform[] hierarchy, Transform root)
{
if (bones == null || bones.Length != hierarchy.Length)
{
bones = new Bone[hierarchy.Length];
}
for (int i = 0; i < hierarchy.Length; i++)
{
if (bones[i] == null)
{
bones[i] = new Bone();
}
bones[i].transform = hierarchy[i];
}
Initiate(root);
return base.initiated;
}
public void AddBone(Transform bone)
{
Transform[] array = new Transform[bones.Length + 1];
for (int i = 0; i < bones.Length; i++)
{
array[i] = bones[i].transform;
}
array[^1] = bone;
SetChain(array, root);
}
public override void StoreDefaultLocalState()
{
for (int i = 0; i < bones.Length; i++)
{
bones[i].StoreDefaultLocalState();
}
}
public override void FixTransforms()
{
if (base.initiated && !(IKPositionWeight <= 0f))
{
for (int i = 0; i < bones.Length; i++)
{
bones[i].FixTransform();
}
}
}
public override bool IsValid(ref string message)
{
if (bones.Length == 0)
{
message = "IK chain has no Bones.";
return false;
}
if (bones.Length < minBones)
{
message = "IK chain has less than " + minBones + " Bones.";
return false;
}
Bone[] array = bones;
for (int i = 0; i < array.Length; i++)
{
if (array[i].transform == null)
{
message = "One of the Bones is null.";
return false;
}
}
Transform transform = IKSolver.ContainsDuplicateBone(bones);
if (transform != null)
{
message = transform.name + " is represented multiple times in the Bones.";
return false;
}
if (!allowCommonParent && !IKSolver.HierarchyIsValid(bones))
{
message = "Invalid bone hierarchy detected. IK requires for it's bones to be parented to each other in descending order.";
return false;
}
if (!boneLengthCanBeZero)
{
for (int j = 0; j < bones.Length - 1; j++)
{
if ((bones[j].transform.position - bones[j + 1].transform.position).magnitude == 0f)
{
message = "Bone " + j + " length is zero.";
return false;
}
}
}
return true;
}
public override Point[] GetPoints()
{
return bones;
}
public override Point GetPoint(Transform transform)
{
for (int i = 0; i < bones.Length; i++)
{
if (bones[i].transform == transform)
{
return bones[i];
}
}
return null;
}
protected override void OnInitiate()
{
}
protected override void OnUpdate()
{
}
protected void InitiateBones()
{
chainLength = 0f;
for (int i = 0; i < bones.Length; i++)
{
if (i < bones.Length - 1)
{
bones[i].length = (bones[i].transform.position - bones[i + 1].transform.position).magnitude;
chainLength += bones[i].length;
Vector3 position = bones[i + 1].transform.position;
bones[i].axis = Quaternion.Inverse(bones[i].transform.rotation) * (position - bones[i].transform.position);
if (bones[i].rotationLimit != null)
{
if (XY && !(bones[i].rotationLimit is RotationLimitHinge))
{
Warning.Log("Only Hinge Rotation Limits should be used on 2D IK solvers.", bones[i].transform);
}
bones[i].rotationLimit.Disable();
}
}
else
{
bones[i].axis = Quaternion.Inverse(bones[i].transform.rotation) * (bones[bones.Length - 1].transform.position - bones[0].transform.position);
}
}
}
protected Vector3 GetSingularityOffset()
{
if (!SingularityDetected())
{
return Vector3.zero;
}
Vector3 normalized = (IKPosition - bones[0].transform.position).normalized;
Vector3 rhs = new Vector3(normalized.y, normalized.z, normalized.x);
if (useRotationLimits && bones[bones.Length - 2].rotationLimit != null && bones[bones.Length - 2].rotationLimit is RotationLimitHinge)
{
rhs = bones[bones.Length - 2].transform.rotation * bones[bones.Length - 2].rotationLimit.axis;
}
return Vector3.Cross(normalized, rhs) * bones[bones.Length - 2].length * 0.5f;
}
private bool SingularityDetected()
{
if (!base.initiated)
{
return false;
}
Vector3 vector = bones[bones.Length - 1].transform.position - bones[0].transform.position;
Vector3 vector2 = IKPosition - bones[0].transform.position;
float magnitude = vector.magnitude;
float magnitude2 = vector2.magnitude;
if (magnitude < magnitude2)
{
return false;
}
if (magnitude < chainLength - bones[bones.Length - 2].length * 0.1f)
{
return false;
}
if (magnitude == 0f)
{
return false;
}
if (magnitude2 == 0f)
{
return false;
}
if (magnitude2 > magnitude)
{
return false;
}
if (Vector3.Dot(vector / magnitude, vector2 / magnitude2) < 0.999f)
{
return false;
}
return true;
}
}
}