Unity Shader 屏幕颜色混淆干扰(杂色)

效果如图：

以下是shader代码：

Shader "Custom/ScreenNoise"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
        _NoiseIntensity ("Noise Intensity", Range(0, 1)) = 0
        _ColorVariation ("Color Variation", Range(0, 1)) = 0.5
    }
    SubShader
    {
        Pass
        {
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            
            #include "UnityCG.cginc"

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

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

            sampler2D _MainTex;
            float _NoiseIntensity;
            float _ColorVariation;

            float random (float2 uv)
            {
                return frac(sin(dot(uv, float2(12.9898,78.233))) * 43758.5453);
            }

            v2f vert (appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = v.uv;
                return o;
            }
            
            fixed4 frag (v2f i) : SV_Target
            {
                fixed4 col = tex2D(_MainTex, i.uv);
                float noise = random(i.uv + _Time.y);
                
                if(_NoiseIntensity > 0)
                {
                    float3 noiseColor = float3(
                        random(i.uv + float2(0.1, 0.1)),
                        random(i.uv + float2(0.2, 0.2)),
                        random(i.uv + float2(0.3, 0.3))
                    );
                    
                    col.rgb = lerp(col.rgb, noiseColor, _NoiseIntensity * _ColorVariation);
                    col.rgb = lerp(col.rgb, col.rgb * (1 + noise * 0.5), _NoiseIntensity * 0.3);
                }
                
                return col;
            }
            ENDCG
        }
    }
}

创建屏幕效果脚本

using UnityEngine;

[ExecuteInEditMode]
public class ScreenNoiseEffect : MonoBehaviour
{
    public float noiseIntensity = 0f;
    public float colorVariation = 0.5f;
    
    private Material noiseMaterial;
    private static ScreenNoiseEffect instance;

    void Awake()
    {
        instance = this;
        noiseMaterial = new Material(Shader.Find("Custom/ScreenNoise"));
    }

    void OnRenderImage(RenderTexture src, RenderTexture dest)
    {
        if (noiseMaterial != null && noiseIntensity > 0)
        {
            noiseMaterial.SetFloat("_NoiseIntensity", noiseIntensity);
            noiseMaterial.SetFloat("_ColorVariation", colorVariation);
            Graphics.Blit(src, dest, noiseMaterial);
        }
        else
        {
            Graphics.Blit(src, dest);
        }
    }

    public static void SetNoiseIntensity(float intensity)
    {
        if (instance != null)
        {
            instance.noiseIntensity = Mathf.Clamp01(intensity);
        }
    }
}