NAK_CVR_Mods/DesktopVRIK/DesktopVRIK.cs

using ABI.CCK.Components;
using ABI_RC.Core.Player;
using ABI_RC.Systems.IK;
using ABI_RC.Systems.IK.SubSystems;
using ABI_RC.Systems.MovementSystem;
using RootMotion.FinalIK;
using UnityEngine;
using UnityEngine.Events;

namespace DesktopVRIK;

public class DesktopVRIK : MonoBehaviour
{
    public static DesktopVRIK Instance;

    public bool Setting_Enabled, 
        Setting_EmulateVRChatHipMovement,
        Setting_EnforceViewPosition, 
        Setting_EmoteVRIK, 
        Setting_EmoteLookAtIK,
        Setting_PlantFeet;
    public float Setting_EmulateVRChatHipMovementWeight;

    public Transform viewpoint;
    public Vector3 initialCamPos;

    void Start()
    {
        Instance = this;
    }

    public void ChangeViewpointHandling(bool enabled)
    {
        Setting_EnforceViewPosition = enabled;
        if (enabled)
        {
            PlayerSetup.Instance.desktopCamera.transform.localPosition = Vector3.zero;
            return;
        }
        PlayerSetup.Instance.desktopCamera.transform.localPosition = initialCamPos;
    }
    
    public void OnPreSolverUpdate()
    {
        //Reset avatar offset (VRIK will literally make you walk away from root otherwise)
        IKSystem.vrik.transform.localPosition = Vector3.zero;
        IKSystem.vrik.transform.localRotation = Quaternion.identity;
        //VRChat hip movement emulation
        if (Setting_EmulateVRChatHipMovement)
        {
            float angle = PlayerSetup.Instance.desktopCamera.transform.localEulerAngles.x;
            angle = (angle > 180) ? angle - 360 : angle;
            float weight = (Setting_EmulateVRChatHipMovementWeight - MovementSystem.Instance.movementVector.magnitude);
            Quaternion rotation = Quaternion.AngleAxis(angle * weight, IKSystem.Instance.avatar.transform.right);
            IKSystem.vrik.solver.AddRotationOffset(IKSolverVR.RotationOffset.Head, rotation);
        }
        IKSystem.vrik.solver.plantFeet = Setting_PlantFeet;
    }

    public void CalibrateDesktopVRIK(CVRAvatar avatar)
    {
        //Stuff to make bad armatures work (Fuck you Default Robot Kyle)
        IKSystem.Instance.animator.cullingMode = AnimatorCullingMode.AlwaysAnimate;
        avatar.transform.localPosition = Vector3.zero;
        Quaternion originalRotation = avatar.transform.rotation;
        avatar.transform.rotation = Quaternion.identity;

        //Generic VRIK calibration shit

        IKSystem.vrik.fixTransforms = false;
        IKSystem.vrik.solver.plantFeet = false;
        IKSystem.vrik.solver.locomotion.weight = 1f;
        IKSystem.vrik.solver.locomotion.angleThreshold = 30f;
        IKSystem.vrik.solver.locomotion.maxLegStretch = 0.75f;
        //nuke weights
        IKSystem.vrik.solver.spine.headClampWeight = 0f;
        IKSystem.vrik.solver.spine.minHeadHeight = 0f;
        IKSystem.vrik.solver.leftArm.positionWeight = 0f;
        IKSystem.vrik.solver.leftArm.rotationWeight = 0f;
        IKSystem.vrik.solver.rightArm.positionWeight = 0f;
        IKSystem.vrik.solver.rightArm.rotationWeight = 0f;
        IKSystem.vrik.solver.leftLeg.positionWeight = 0f;
        IKSystem.vrik.solver.leftLeg.rotationWeight = 0f;
        IKSystem.vrik.solver.rightLeg.positionWeight = 0f;
        IKSystem.vrik.solver.rightLeg.rotationWeight = 0f;

        //ChilloutVR specific stuff

        //Find eyeoffset
        initialCamPos = PlayerSetup.Instance.desktopCamera.transform.localPosition;
        Transform headTransform = IKSystem.Instance.animator.GetBoneTransform(HumanBodyBones.Head);
        viewpoint = headTransform.Find("LocalHeadPoint");
        ChangeViewpointHandling(Setting_EnforceViewPosition);

        //centerEyeAnchor now is head bone
        Transform headAnchor = FindIKTarget(headTransform);
        IKSystem.Instance.headAnchorPositionOffset = Vector3.zero;
        IKSystem.Instance.headAnchorRotationOffset = headAnchor.rotation.eulerAngles; //set to head bone world rotation (Fuck you Default Robot Kyle)
        IKSystem.Instance.ApplyAvatarScaleToIk(avatar.viewPosition.y);
        BodySystem.TrackingLeftArmEnabled = false;
        BodySystem.TrackingRightArmEnabled = false;
        BodySystem.TrackingLeftLegEnabled = false;
        BodySystem.TrackingRightLegEnabled = false;
        IKSystem.vrik.solver.IKPositionWeight = 0f;
        IKSystem.vrik.enabled = false;

        //Calibrate HeadIKOffset *(this is fucked on some avatars, (Fuck you Default Robot Kyle) but setting headAnchorRotationOffset to head rotation fixes (Fuck you Default Robot Kyle))*
        VRIKCalibrator.CalibrateHead(IKSystem.vrik, headAnchor, IKSystem.Instance.headAnchorPositionOffset, IKSystem.Instance.headAnchorRotationOffset);

        IKSystem.vrik.enabled = true;
        IKSystem.vrik.solver.IKPositionWeight = 1f;
        IKSystem.vrik.solver.spine.maintainPelvisPosition = 0f;
        if (IKSystem.vrik != null)
        {
            IKSystem.vrik.onPreSolverUpdate.AddListener(new UnityAction(this.OnPreSolverUpdate));
        }

        //(Fuck you Default Robot Kyle).. oh wait nvm, not related
        avatar.transform.rotation = originalRotation;
        IKSystem.Instance.ResetIK();
    }

    //This is built because original build placed IK Targets on all joints.
    private static Transform FindIKTarget(Transform targetParent)
    {
        /**
            I want creators to be able to specify their own custom IK Targets, so they can move them around with animations if they want.
            We check for existing target objects, and if none are found we make our own.
            Naming scheme is parentobject name + " IK Target".
        **/
        Transform parentTransform = targetParent.transform;
        string targetName = parentTransform.name + " IK Target";

        //check for existing target
        foreach (object obj in parentTransform)
        {
            Transform childTransform = (Transform)obj;
            if (childTransform.name == targetName)
            {
                return childTransform;
            }
        }

        //create new target if none are found
        GameObject newTarget = new GameObject(targetName);
        newTarget.transform.parent = parentTransform;
        newTarget.transform.localPosition = Vector3.zero;
        newTarget.transform.localRotation = Quaternion.identity;
        return newTarget.transform;
    }
}