Softbody for a certain region - Printable Version

Code:
using System.Collections;

using UnityEngine;

using Obi;

using ExternalPropertyAttributes;

using System;

using CurvedUI;

using System.Collections.Generic;

using System.Linq;



public class BoobsInteraction : MonoBehaviour

{

    [System.Serializable]

    public class BonesWithWeights

    {

        public string BoneName;

        public float WeightThreshold;

    }



    public Transform UpperChest;

    public SkinnedMeshRenderer BodyRenderer;

    public List<SkinnedMeshRenderer> AdditionalRenderers = new List<SkinnedMeshRenderer>();

    public ObiSoftbody SofbodyPrefab;

    public float DefaultBoobsHeight = 1.13f;

    public List<BonesWithWeights> bonesThresholds = new List<BonesWithWeights>()

    {

        new BonesWithWeights() { BoneName = "Bust1", WeightThreshold = 0.75f},

        new BonesWithWeights() { BoneName = "Bust2", WeightThreshold = 0.0f }

    };



    private ObiParticleAttachment _attachment;



    private struct BoneWithThreshold {

        public int BoneIndex;

        public float Threshold;

    }





        [Button]

    public void Initialize()

    {

        if (UpperChest == null) throw new ArgumentNullException($"Property {nameof(UpperChest)} is not set");

        if (BodyRenderer == null) throw new ArgumentNullException($"Property {nameof(BodyRenderer)} is not set");

        if (SofbodyPrefab == null) throw new ArgumentNullException($"Property {nameof(SofbodyPrefab)} is not set");





        ObiSoftbody softbodyInstance = GameObject.Instantiate(SofbodyPrefab);

        softbodyInstance.transform.position = BodyRenderer.transform.position;

        try

        {

            softbodyInstance.softbodyBlueprint = SetupBlueprint();

        } catch (Exception ex)

        {

            Debug.LogException(ex, this);

            float delta = BodyRenderer.transform.position.y + DefaultBoobsHeight - UpperChest.position.y;

            softbodyInstance.transform.position = BodyRenderer.transform.position - new Vector3(0.0f, delta, 0.0f);

        }



        _attachment = softbodyInstance.AddComponentIfMissing<ObiParticleAttachment>();

        _attachment.target = UpperChest;



        var bodySkinner = BodyRenderer.AddComponentIfMissing<ObiSoftbodySkinner>();

        bodySkinner.Source = softbodyInstance;

        bodySkinner.m_SkinningMaxDistance = 0.05f;



        IEnumerator bind = bodySkinner.BindSkin();

        while (bind.MoveNext()) { }



        foreach (var renderer in AdditionalRenderers)

        {

            var additionalSkinner = renderer.AddComponentIfMissing<ObiSoftbodySkinner>();

            additionalSkinner.Source = softbodyInstance;

            additionalSkinner.m_SkinningMaxDistance = 0.05f;



            IEnumerator additionalBind = additionalSkinner.BindSkin();

            while (additionalBind.MoveNext()) { }

        }



        softbodyInstance.transform.SetParent(BodyRenderer.transform);

        softbodyInstance.transform.localPosition = Vector3.zero;

    }



    private ObiSoftbodySurfaceBlueprint SetupBlueprint()

    {

        var blueprint = ScriptableObject.CreateInstance<ObiSoftbodySurfaceBlueprint>();



        // set the blueprint's particle radius and cluster radius:

        blueprint.inputMesh = BodyRenderer.sharedMesh;

        blueprint.surfaceSamplingMode = ObiSoftbodySurfaceBlueprint.SurfaceSamplingMode.Vertices;

        blueprint.surfaceResolution = 48;

        blueprint.GenerateImmediate();



        List<BoneWithThreshold> boneIndeces = new List<BoneWithThreshold>();

        for (int i = 0; i < BodyRenderer.bones.Length; i++)

        {

            for(int j=0; j < bonesThresholds.Count; j++)

            {

                if (BodyRenderer.bones[i].name.Contains(bonesThresholds[j].BoneName))

                {

                    boneIndeces.Add(new BoneWithThreshold()

                    {

                        BoneIndex = i,

                        Threshold = bonesThresholds[j].WeightThreshold

                    });

                }



            }

        }



        Mesh mesh = BodyRenderer.sharedMesh;



        HashSet<int> bonesParticles = new();



        for (int i = 0; i < mesh.vertexCount; i++)

        {

            BoneWeight boneWeight = mesh.boneWeights[i];

            for(int j=0; j < boneIndeces.Count; j++)

            {

                if(boneIndeces[j].BoneIndex == boneWeight.boneIndex0 && boneWeight.weight0 >= boneIndeces[j].Threshold ||

                    boneIndeces[j].BoneIndex == boneWeight.boneIndex1 && boneWeight.weight1 >= boneIndeces[j].Threshold ||

                    boneIndeces[j].BoneIndex == boneWeight.boneIndex2 && boneWeight.weight2 >= boneIndeces[j].Threshold ||

                    boneIndeces[j].BoneIndex == boneWeight.boneIndex3 && boneWeight.weight3 >= boneIndeces[j].Threshold)

                {

                    bonesParticles.Add(blueprint.vertexToParticle[i]);

                    var cube = GameObject.CreatePrimitive(PrimitiveType.Cube);

                    cube.transform.localScale = Vector3.one * 0.01f;

                    cube.transform.position = BodyRenderer.transform.TransformPoint(mesh.vertices[i]);

                    cube.transform.SetParent(BodyRenderer.transform, true);

                }

            }

        }



        bool[] selectedParticles = new bool[blueprint.particleCount];



        for (int i = 0; i < blueprint.particleCount; i++)

        {

            if (bonesParticles.Contains(i))

            {

                selectedParticles[i] = false;

            }

            else

            {

                selectedParticles[i] = true;

            }

        }

        blueprint.distanceConstraintsData = new();

        blueprint.bendConstraintsData = new();

        blueprint.RemoveSelectedParticles(ref selectedParticles, true);

        var group = blueprint.AppendNewParticleGroup("chest");

        for (int i = 0; i < selectedParticles.Length; i++)

        {

            if (selectedParticles[i])

            {

                group.particleIndices.Add(i);

            }

        }



        return blueprint;

    }



}