Unity Shader 使用枚举切换整体色调

系统管理员 2022-06-01 00:17 246阅读 0赞

# 效果图： #

![这里写图片描述][20180115151345031]

# 知识点： #

*  两种方式在shader中使用枚举
 *  脚本修改shader中的变量
 *  两种方式遍历枚举对象
 *  使用协程执行定时逻辑

# 代码 #

## 一、颜色变化的枚举类型，其值是byte类型的 ##

using System.Collections;
    using System.Collections.Generic;
    using UnityEngine;
    
    public enum ColorType : byte{
        First = 1,
        Second = 2,
        Third = 3,
        Fourth = 4,
        Fifth = 5,
        Sixth = 6,
    }

## 二、循环遍历控制逻辑 ##

*  这里将切换逻辑写在协程里，而不是Update中，这样有利于程序的模块化
 *  有两种方式实现遍历，一种是通过数组和索引，另一种则是迭代器

using System.Collections;
    using System.Collections.Generic;
    using UnityEngine;
    using System;
    
    public class AutoChangeColor : MonoBehaviour {
    
        /// <summary>
        /// 改变颜色的时间间隔
        /// </summary>
        public int changeInterval = 1;
    
        public Material mat;
    
        // Use this for initialization
        void Start() {
            StartCoroutine(ChangeColor2());
        }
    
        // Update is called once per frame
        void Update() {
    
        }
    
        private IEnumerator ChangeColor1()
        {
            Byte[] colorTypes = (Byte[])Enum.GetValues(typeof(ColorType));
            byte index = 0;
            while (true)
            {
                mat.SetInt("_ColorType", colorTypes[index]);
                yield return new WaitForSeconds(changeInterval);
                index++;
                if(index == colorTypes.Length)
                {
                    index = 0;
                }
            }
        }
    
        private IEnumerator ChangeColor2()
        {
            Array colorTypeArray = Enum.GetValues(typeof(ColorType));
            IEnumerator it = colorTypeArray.GetEnumerator();
            while(true) { 
                if (it.MoveNext()) {
                    print("name = " + it.Current + ", value = " + (byte)it.Current);
                    mat.SetInt("_ColorType", (byte)it.Current);
                    yield return new WaitForSeconds(changeInterval);
                } else
                {
                    it.Reset();
                }
            }
        }
    }

## 三、UnlitShader 无光着色器 ##

在shader中有两种方式可以定义枚举类型：

*  键值对的数组形式
 *  引用C\#中定义的包名加类型的方式

![这里写图片描述][20180115154946184]

Shader "Custom/UnlitColorChangeShader"
    {
        Properties
        {
            _MainTex ("Texture", 2D) = "white" {}
            [Enum(First,1,Second,2,Third,3,Fourth,4,Fifth,5,Sixth,6)] _ColorType ("Color Type", Int) = 1   
            //[Enum(ColorType)] _ColorType ("Color Type", Int) = 1
        }
        SubShader
        {
            Tags { "RenderType"="Opaque" }
            LOD 100
    
            Pass
            {
                CGPROGRAM
                #pragma vertex vert
                #pragma fragment frag
                // make fog work
                #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;
                float _ColorType;
    
                v2f vert (appdata v)
                {
                    v2f 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
                {
                    // sample the texture
                    fixed4 col = tex2D(_MainTex, i.uv);
                    // apply fog
                    UNITY_APPLY_FOG(i.fogCoord, col);
                    //return 1 - col;
                    fixed4 newCol;
                    switch(_ColorType) {
                        case 2:
                            newCol = fixed4(col.x, col.z, col.y, col.w);
                            break;
                        case 3:
                            newCol = fixed4(col.y, col.x, col.z, col.w);
                            break;
                        case 4:
                            newCol = fixed4(col.y, col.z, col.x, col.w);
                            break;
                        case 5:
                            newCol = fixed4(col.z, col.x, col.y, col.w);
                            break;
                        case 6:
                            newCol = fixed4(col.z, col.y, col.x, col.w);
                            break;
                        default:
                            newCol = fixed4(col.x, col.y, col.z, col.w);
                            break;
                    }
                    return newCol;
                }
                ENDCG
            }
        }
    }

[20180115151345031]: /images/20220601/f88cf62b6c904f00981ca0957fcd0fac.png
[20180115154946184]: /images/20220601/3f1ab82e49324a77aed90c892e0e0d87.png