蛮好玩的效果，具体demo在帖子最后！

Yesterday, playing with vertex manipulation in Unity editor, I made this small script that simulate a rubber material. It´s inspired on Flex modifier of 3ds Max, where you can set the weight of each vertex and then apply gravity and inertial effect over it.

To use it just drag the script to your game object.
Your 3d object need to have VertexColors to define the intensity of the effect over each vertex. The black color defines the heaviest vertex and more intense effect.

Check te example

3d Model:

Vertex Color:

RubberEffect.cs

 

/* ******************************************************************************************************* *
 * RUBBER EFFECT                                                                                           *
 * You need to set the Vertex Colors of your 3d model, on your prefered 3d Modelling Tool                  *
 * by Rodrigo Pegorari - 2010 - http://rodrigopegorari.net                                                 *
 * based on the Processing 'Chain' code example (http://www.processing.org/learning/topics/chain.html)     *
 * ******************************************************************************************************* */

using UnityEngine;
using System.Collections;

public class RubberEffect : MonoBehaviour
{

    public RubberType Presets;

    public enum RubberType
    {
        Custom,
        RubberDuck,
        HardRubber,
        Jelly,
        SoftLatex
    }

    public float EffectIntensity = 1;
    public float gravity = 0;
    public float damping = 0.7f;
    public float mass = 1;
    public float stiffness = 0.2f;
   

    private Mesh WorkingMesh;
    private Mesh OriginalMesh;
    private float[] ColorIntensity;
    private VertexRubber[] vr;

    internal class VertexRubber
    {
        public float v_gravity;
        public float v_mass;
        public float v_stiffness;
        public float v_damping;
        public Vector3 pos;

        Vector3 vel = new Vector3();

        public VertexRubber(Vector3 v_target, float m, float g, float s, float d)
        {
            v_gravity = g;
            v_mass = m;
            v_stiffness = s;
            v_damping = d;

            pos = v_target;
        }

        public void update(Vector3 target)
        {

            Vector3 force = new Vector3();
            Vector3 acc = new Vector3();

            force.x = (target.x - pos.x) * v_stiffness;
            acc.x = force.x / v_mass;
            vel.x = v_damping * (vel.x + acc.x);
            pos.x += vel.x;

            force.y = (target.y - pos.y) * v_stiffness;
            force.y -= v_gravity / 10;
            acc.y = force.y / v_mass;
            vel.y = v_damping * (vel.y + acc.y);
            pos.y += vel.y;

            force.z = (target.z - pos.z) * v_stiffness;
            acc.z = force.z / v_mass;
            vel.z = v_damping * (vel.z + acc.z);
            pos.z += vel.z;

        }

    }

   
    void Start(){

        Debug.Log(Presets);
        MeshFilter filter = (MeshFilter)GetComponent(typeof(MeshFilter));
        OriginalMesh = filter.sharedMesh;

        WorkingMesh = Instantiate(filter.sharedMesh) as Mesh;
        filter.sharedMesh = WorkingMesh;

        ColorIntensity = new float[OriginalMesh.vertices.Length];

        vr = new VertexRubber[OriginalMesh.vertices.Length];

        for (int i = 0; i < OriginalMesh.vertices.Length; i++)
        {
            ColorIntensity[i] = (1 - ((OriginalMesh.colors[i].r + OriginalMesh.colors[i].g + OriginalMesh.colors[i].b) / 3)) * EffectIntensity;
            vr[i] = new VertexRubber(transform.TransformPoint(OriginalMesh.vertices[i]), mass, gravity, stiffness, damping);
        }

    }

    void Update()
    {

        checkPreset();

        Vector3[] V3_WorkingMesh = OriginalMesh.vertices;

        for (int i = 0; i < V3_WorkingMesh.Length; i++)
        {
            if (!float.Equals(ColorIntensity[i],0f)){

                Vector3 v3_target = transform.TransformPoint(V3_WorkingMesh[i]);

                vr[i].v_gravity = gravity;
                vr[i].v_mass = mass;
                vr[i].v_stiffness = stiffness;
                vr[i].v_damping = damping;

                vr[i].update(v3_target);

                v3_target = transform.InverseTransformPoint(vr[i].pos);

                V3_WorkingMesh[i] = Vector3.Lerp(V3_WorkingMesh[i], v3_target, ColorIntensity[i] * EffectIntensity);

            }

        }

        WorkingMesh.vertices = V3_WorkingMesh;
        WorkingMesh.RecalculateBounds();

    }

    void checkPreset() {
           
        switch (Presets)
        {
            case RubberType.HardRubber:
                gravity = 0f;
                mass = 8f;
                stiffness = 0.5f;
                damping = 0.9f;
                EffectIntensity = 0.5f;
                break;
            case RubberType.Jelly:
                gravity = 0f;
                mass = 1f;
                stiffness = 0.95f;
                damping = 0.95f;
                EffectIntensity = 1f;
                break;
            case RubberType.RubberDuck:
                gravity = 0f;
                mass = 2f;
                stiffness = 0.5f;
                damping = 0.85f;
                EffectIntensity = 1f;
                break;
            case RubberType.SoftLatex:
                gravity = 1f;
                mass = 0.9f;
                stiffness = 0.3f;
                damping = 0.25f;
                EffectIntensity = 1f;
                break;
        }
   
    }

}

资源包文件在附件中

本文转自http://forum.unity3d.com/viewtopic.php?t=48131&highlight=rubbereffect