DrawMeshInstanced雛形

PieceData.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Rendering;

public class PieceData {

    public Vector3 pos = new Vector3(
        5f * ( Random.value-0.5f ),
        5f * ( Random.value-0.5f ),
        5f * ( Random.value-0.5f )       
    );
    public Quaternion rot =Quaternion.Euler(0,0,0);
    public Vector3 scale = new Vector3(1f,1f,1f);

    public Vector4 uv = new Vector4();

}

Pieces.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Rendering;

public class Pieces : MonoBehaviour {

    [SerializeField] protected Mesh _mesh;
    [SerializeField] protected Material _mat;
    protected Matrix4x4[] _matrices;
    protected Vector4[] _colors;
    protected MaterialPropertyBlock _propertyBlock;
    protected int _count = 400;
    private PieceData[] _data;
    public const int MAX = 1023;

    void Start(){

        _propertyBlock = new MaterialPropertyBlock();
        _matrices = new Matrix4x4[MAX];
        _data = new PieceData[MAX];
        _colors = new Vector4[MAX];
        //_uvs = new Vector4[MAX];

        _count=0;
        for(int i=0;i<MAX;i++){

            _matrices[_count] = Matrix4x4.identity;
            _data[_count] = new PieceData();

            _data[_count].pos.x = 2f * ( Random.value-0.5f );
            _data[_count].pos.y = 2f * ( Random.value-0.5f );
            _data[_count].pos.z = 2f * ( Random.value-0.5f );

            _data[_count].rot = Quaternion.Euler(
                Random.value * 360f,
                Random.value * 360f,
                Random.value * 360f
            );
            //_uvs[_count] = SpriteUV.GetUv(Mathf.FloorToInt(Random.value*6),4,4);
            _colors[_count] = new Vector4(
                Random.value,
                Random.value,
                Random.value,
                1f
            );
            _count++;
            
        }

    }


    void Update(){

        for (int i = 0; i < _count; i++)
        {
            _matrices[i].SetTRS( 
                _data[i].pos,
                _data[i].rot,
                _data[i].scale
            );
            _matrices[i] = transform.localToWorldMatrix * _matrices[i];

        }

        _propertyBlock.SetVectorArray("_Color", _colors);
        //_propertyBlock.SetVectorArray("_Uv", _uvs);

        Graphics.DrawMeshInstanced(
                _mesh, 
                0, 
                _mat, 
                _matrices, 
                _count, 
                _propertyBlock, 
                ShadowCastingMode.On, 
                false, 
                gameObject.layer
        );

    }

}

Pieces.shader

// Upgrade NOTE: upgraded instancing buffer 'Props' to new syntax.

Shader "pieces/Pieces"
{
    Properties
    {
        _Color ("Color", Vector) = (1.0, 0.0, 0.0, 1.0)
        _MainTex ("_MainTex", 2D) = "white" {}
        _Th ("_Th", Range(0,1)) = 0.5

    }
    SubShader
    {
        //Tags { "RenderType"="Opaque" }
        Tags { "RenderType"="Transparent" "Queue"="Transparent" }
        Blend SrcAlpha OneMinusSrcAlpha
        LOD 100
        cull off
        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            // make fog work
            #pragma multi_compile_fog

            #pragma multi_compile_instancing

            #include "UnityCG.cginc"

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

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

            sampler2D _MainTex;
            float4 _MainTex_ST;
            float _Th;

            UNITY_INSTANCING_BUFFER_START(Props)
                UNITY_DEFINE_INSTANCED_PROP(fixed4, _Color) // Make _Color an instanced property (i.e. an array)
                #define _Color_arr Props
                UNITY_DEFINE_INSTANCED_PROP(fixed4, _Uv) // Make _Color an instanced property (i.e. an array)
                #define _Uv_arr Props
            UNITY_INSTANCING_BUFFER_END(Props)

            v2f vert (appdata v)
            {
                v2f o;

                //インスタンス ID がシェーダー関数にアクセス可能になります。頂点シェーダーの最初に使用する必要があります
                UNITY_SETUP_INSTANCE_ID (v);

                //頂点シェーダーで入力構造体から出力構造体へインスタンス ID をコピーします。
                //フラグメントシェーダーでは、インスタンスごとのデータにアクセスするときのみ必要です
                UNITY_TRANSFER_INSTANCE_ID (v, o);

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

                return o;
            }

            fixed4 frag (v2f i) : SV_Target
            {
                UNITY_SETUP_INSTANCE_ID (i);

                    // 変数にアクセス
                fixed4 col = UNITY_ACCESS_INSTANCED_PROP(_Color_arr, _Color);

                //fixed4 uvv = UNITY_ACCESS_INSTANCED_PROP(_Uv_arr, _Uv);
                //fixed4 tex = tex2D(_MainTex, uvv.xy + i.uv*uvv.zw);
                //clip(tex.a - _Th);
                // apply fog
                //UNITY_APPLY_FOG(i.fogCoord, col);

                return col;//tex;
            }
            ENDCG
        }
    }
}

PiecesSurf.shader

// Upgrade NOTE: upgraded instancing buffer 'Props' to new syntax.

Shader "pieces/PiecesSurf" {
	Properties {
		_Color ("Color", Color) = (1,1,1,1)
		_MainTex ("Albedo (RGB)", 2D) = "white" {}
		_Glossiness ("Smoothness", Range(0,1)) = 0.5
		_Metallic ("Metallic", Range(0,1)) = 0.0
		_Amount ("_Amount", Range(0,5)) = 0.0
	}
	SubShader {
		Tags { "RenderType"="Opaque" }
		LOD 200
		
		CGPROGRAM
		// Physically based Standard lighting model, and enable shadows on all light types
		//#pragma surface surf Standard fullforwardshadows
		#pragma surface surf Standard addshadow vertex:vert

		// Use shader model 3.0 target, to get nicer looking lighting
		#pragma target 3.0

		sampler2D _MainTex;

		struct Input {
			float2 uv_MainTex;
		};

		half _Glossiness;
		half _Metallic;
		//fixed4 _Color;
		float _Amount;

        UNITY_INSTANCING_BUFFER_START(Props)
            UNITY_DEFINE_INSTANCED_PROP(fixed4, _Color) // Make _Color an instanced property (i.e. an array)
            #define _Color_arr Props
        UNITY_INSTANCING_BUFFER_END(Props)

        void vert(inout appdata_full v, out Input o )
        {
            UNITY_INITIALIZE_OUTPUT(Input, o);
			

            //インスタンス ID がシェーダー関数にアクセス可能になります。頂点シェーダーの最初に使用する必要があります
            UNITY_SETUP_INSTANCE_ID (v);

            //頂点シェーダーで入力構造体から出力構造体へインスタンス ID をコピーします。
            //フラグメントシェーダーでは、インスタンスごとのデータにアクセスするときのみ必要です
            //UNITY_TRANSFER_INSTANCE_ID (v, o);            

			//頂点をてきとうに、ごちゃごちゃする、ここではノーマル方向に値を足してる
			//v.vertex.xyz += v.normal.xyz * _Amount;
		}

		void surf (Input IN, inout SurfaceOutputStandard o) {

            //UNITY_SETUP_INSTANCE_ID (IN);

            fixed4 col = UNITY_ACCESS_INSTANCED_PROP(_Color_arr, _Color);

			// Albedo comes from a texture tinted by color
			fixed4 c = tex2D (_MainTex, IN.uv_MainTex) * col;
			o.Albedo = c.rgb*0.5;
            o.Emission = c.rgb*0.5;
			// Metallic and smoothness come from slider variables
			o.Metallic = _Metallic;
			o.Smoothness = _Glossiness;
			o.Alpha = c.a;
		}
		ENDCG
	}
	FallBack "Diffuse"
}