统一,修改标准着色器以随机翻转纹理?

. 我还没找到办法,你也不行。

这是一个应该用C端代码来解决的问题。

(1) 生成几个不同版本的 材质,每个具有不同的平铺,并随机选择其中一个

一点问题都没有。这是什么 MaterialPropertyBlock

如果要使用相同的材质绘制多个对象,但属性略有不同,请使用它

下面的代码将导致创建许多材质实例:

void Start()
{
    MeshRenderer meshRenderer = gameObject.GetComponent<MeshRenderer>();
    int tileX = (UnityEngine.Random.Range(1, 3) == 1) ? 1 : -1;
    int tileY = (UnityEngine.Random.Range(1, 3) == 1) ? 1 : -1;
    Vector2 tile = new Vector2(tileX, tileY);
    meshRenderer.material.SetTextureScale("_MainTex", tile);
}

与 材料属性块 ,这个问题就解决了。未制作材料副本。既然你关心性能,你也应该使用 Shader.PropertyToID :

void Start()
{
    int propertyID = Shader.PropertyToID("_MainTex_ST");
    meshRenderer = gameObject.GetComponent<MeshRenderer>();
    int tileX = (UnityEngine.Random.Range(1, 3) == 1) ? 1 : -1;
    int tileY = (UnityEngine.Random.Range(1, 3) == 1) ? 1 : -1;
    Vector2 tile = new Vector2(tileX, tileY);

    MaterialPropertyBlock matPropBlock = new MaterialPropertyBlock();
    //Get the current MaterialPropertyBlock settings
    meshRenderer.GetPropertyBlock(matPropBlock);
    //Assign the new tile value
    matPropBlock.SetVector(propertyID, tile);
    //matPropBlock.SetVector(Shader.PropertyToID("_MainTex_ST"), tile);
    //Apply the modified MaterialPropertyBlock back to the renderer
    meshRenderer.SetPropertyBlock(matPropBlock);
}

如果在游戏中只执行一次,那么将脚本附加到每个游戏对象就没有意义了。只需将它附加到一个空的游戏对象上,按标签找到所有对象,然后在每个对象上运行代码。

void Start()
{
    GameObject[] objs = GameObject.FindGameObjectsWithTag("YourObjTag");
    int propertyID = Shader.PropertyToID("_MainTex_ST");
    for (int i = 0; i < objs.Length; i++)
    {
        MeshRenderer meshRenderer = objs[i].GetComponent<MeshRenderer>();
        int tileX = (UnityEngine.Random.Range(1, 3) == 1) ? 1 : -1;
        int tileY = (UnityEngine.Random.Range(1, 3) == 1) ? 1 : -1;
        Vector2 tile = new Vector2(tileX, tileY);

        MaterialPropertyBlock matPropBlock = new MaterialPropertyBlock();
        //Get the current MaterialPropertyBlock settings
        meshRenderer.GetPropertyBlock(matPropBlock);
        //Assign the new tile value
        matPropBlock.SetVector(propertyID, tile);
        //Apply the modified MaterialPropertyBlock back to the renderer
        meshRenderer.SetPropertyBlock(matPropBlock);
    }
}

Shader "RandomFlip"
{
Properties
{
    _MainTex ("Texture", 2D) = "white" {}
}
SubShader
{
    Tags { "RenderType"="Opaque" "DisableBatching"="True" }
    LOD 100

    Pass
    {
        CGPROGRAM
        #pragma vertex vert
        #pragma fragment frag
        #pragma multi_compile_fog

        #include "UnityCG.cginc"

        struct appdata
        {
            float4 vertex : POSITION;
            float2 uv : TEXCOORD0;
        };

        struct v2f
        {
            float2 uv : TEXCOORD0;
            UNITY_FOG_COORDS(1)
            float4 vertex : SV_POSITION;
        };

        sampler2D _MainTex;
        float4 _MainTex_ST;

        v2f vert (appdata v)
        {
            // position of pivot in world space
            float3 pivotWorldPos = float3( unity_ObjectToWorld[0].w, unity_ObjectToWorld[1].w, unity_ObjectToWorld[2].w );

            // randomness achieved by feeding trigonometry function with large numbers
            float flipHorizontally = sin( ( pivotWorldPos.x + pivotWorldPos.y + pivotWorldPos.z ) * 1000 ) > 0;
            float flipVertically = cos( ( pivotWorldPos.x + pivotWorldPos.y + pivotWorldPos.z ) * 1000 ) > 0;

            // randomly flipping uvs 
            float2 uv = lerp( v.uv, float2( 1.0 - v.uv.x, v.uv.y ), flipVertically );
            uv = lerp( uv, float2( uv.x, 1.0 - uv.y ), flipHorizontally ); 

            v2f o;
            o.vertex = UnityObjectToClipPos(v.vertex);
            o.uv = TRANSFORM_TEX(uv, _MainTex);
            UNITY_TRANSFER_FOG(o,o.vertex);
            return o;
        }

        fixed4 frag (v2f i) : SV_Target
        {
            // sample the texture
            fixed4 col = tex2D(_MainTex, i.uv);
            // apply fog
            UNITY_APPLY_FOG(i.fogCoord, col);
            return col;
        }
        ENDCG
    }
}
}

尽管你最好不要移动这些物体:D,因为这里的随机性来自于物体在世界空间中的位置。批处理也将打破随机性。

如果要翻转,请对这些对象使用alpha=0,对其他对象使用alpha=1。

半翻转=1-2*顶点a;

所以翻转应该是-1或1。

但是请注意,每次访问 .mesh ,在Unity中,您正在创建一个全新的网格:

public class TestFlipUV : MonoBehaviour
    {
        private void Awake()
        {

            Mesh mesh = GetComponent<MeshFilter>().mesh;
            // NOTE. IN UNITY, ACCESSING .mesh CREATES
            // A NEW INSTANCE OF THAT MESH EVERY TIME

            Vector2[] uv2 = mesh.uv;

            float rnd = Random.RandomRange(0.0f, 1.0f);
            if (rnd > 0.5f)
            {
                for (int i = 0; i < uv2.Length; i++)
                {
                    uv2[i].x *= -1;    
                }
            }

            rnd = Random.RandomRange(0.0f, 1.0f);
            if (rnd > 0.5f)
            {
                for (int i = 0; i < uv2.Length; i++)
                {
                    uv2[i].y *= -1;    
                }
            }
            mesh.uv2 = uv2;
        }
    }

... 然后。。。

Shader "Unlit/FlipUV"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
    }
    SubShader
    {
        Tags { "RenderType"="Opaque" }
        LOD 100

        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag

            #include "UnityCG.cginc"

            struct appdata
            {
                float4 vertex : POSITION;
                float2 uv : TEXCOORD0;
                float2 uv2 : TEXCOORD1;
            };

            struct v2f
            {
                float2 uv : TEXCOORD0;
                float4 vertex : SV_POSITION;
            };

            sampler2D _MainTex;
            float4 _MainTex_ST;
            float4 _MainTex_TexelSize;

            v2f vert (appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = v.uv;
                o.uv *= v.uv2;
                return o;
            }

            fixed4 frag (v2f i) : SV_Target
            {
                fixed4 col = tex2D(_MainTex, i.uv);
                return col;
            }
            ENDCG
        }
    }
}

SetTextureScale

为每个立方体附加。

public class MatTilingChange : MonoBehaviour {
    MeshRenderer mr;
    int[] vals = new int[] { -1, 1 };

    private void Awake()
    {
        mr = GetComponent<MeshRenderer>();
    }

    void Start () {
        mr.material.SetTextureScale("_MainTex", new Vector2(vals[Random.Range(0, 2)], 
vals[Random.Range(0, 2)]));
    }
}