目录
仅裁剪版本
最终版扩展闪烁、消融效果
仅裁剪版本
参考：[SLG] 大地图迷雾实现思路 - 哔哩哔哩
场景布局：地板Scale(40,1,40) 云层Cloud平面Scale(40,1,40) 保持一样大小，将云层平面X和Z值保持与地板一样，Y值拉大，让云层平面正位于地板上空。
新建1个层级：Cloud，云层物体Layer层级设置为Cloud，射线检测只检测这一层的。
其他代码部分相当简单了，就是射线检测拿到uv转局部坐标(x,y)去设置动态生成的遮罩纹理Texture2D(x,y)的像素R通道为0，就达到了裁剪这一个格子效果。
Shader分别用了2个Pass去做，第一个Pass是ShadowCaster（投射阴影）而是这个阴影是被经过Clip裁剪的，一定要开启深度写入（否则不会有阴影）。
第二个Pass则是透明度混合形式裁剪，关闭深度写入的，反正就是直接拿到裁剪图R值作为透明度，其他计算都是为了表现好看点而已。
未实现部分：云层效果、渐变裁剪效果、裁剪提示UI；
疑问：参考文章中的阴影好像并不是我这个样子的，看着不像阴影，只是多了一个深色的云层？
建议不要加阴影，有点怪
Shader "Unlit/FogShader"
{Properties{_MainTex ("Texture", 2D) = "white" {}_MaskTex ("裁剪图", 2D) = "white" {}_MinMaxPowValue("边缘渐变范围(x,y),精度系数(z)", vector) = (1,1,1,1)_NoiseTex ("扰动边缘图", 2D) = "white" {}_NoiseOffsetMultValue ("扰动边缘偏移(x,y),扰动幅度(z)", vector) = (0,0,1,1)_Cutoff ("Alpha Cutoff", Range(0,1)) = 0.5 }SubShader{ Tags{ "Queue" = "AlphaTest" "IgnoreProjector" = "True" "RenderType" = "TransparentCutout" "DisableBatching" = "True" } Pass{//第一个Pass，让物体可以投射阴影,即把该物体加入到相机的深度纹理的计算中, 并进行裁剪Tags{"LightMode"="ShadowCaster"}ZWrite OnCGPROGRAM#pragma vertex vert#pragma fragment frag#pragma multi_compile_shadercaster#include "UnityCG.cginc"sampler2D _MainTex;float4 _MainTex_ST;sampler2D _MaskTex;float4 _MaskTex_ST;fixed _Cutoff; sampler2D _NoiseTex;float4 _MinMaxPowValue;float4 _NoiseOffsetMultValue; struct v2f {V2F_SHADOW_CASTER;float2 uv:TEXCOORD0;};v2f vert(appdata_base v){v2f o;TRANSFER_SHADOW_CASTER_NORMALOFFSET(o);o.uv= TRANSFORM_TEX(v.texcoord, _MaskTex);return o;}//常见算法float ClampAndPowValue(float val, float3 minMaxPow){float mValue;mValue = saturate((val - minMaxPow.x)/(minMaxPow.y - minMaxPow.x)); //边缘数值约束在(Min,Max)范围归一化[0,1] (加快或减缓边缘渐变)mValue = saturate(pow(mValue, minMaxPow.z));//提高边缘精度return mValue;}float4 frag(v2f i) :SV_Target{//对不透明物体不需要下面两行代码，对使用透明度测试的物体，其完全透明部分不会有阴影，要将其剔除 fixed4 col = tex2D(_MainTex, i.uv);float4 noise = tex2D(_NoiseTex, i.uv);float gray = noise.r;float2 disOffset = float2(gray - _NoiseOffsetMultValue.x, gray - _NoiseOffsetMultValue.y) * _NoiseOffsetMultValue.z * 0.01;float4 mask = tex2D(_MaskTex, i.uv + disOffset);float r = mask.r;//裁剪边缘精度、边缘渐变幅度控制r = ClampAndPowValue(r, _MinMaxPowValue.xyz);r = col.a * r;clip(r - _Cutoff); SHADOW_CASTER_FRAGMENT(i)}ENDCG}Pass{Tags{"LightMode" = "ForwardBase"}ZWrite OffBlend SrcAlpha OneMinusSrcAlpha Cull OffCGPROGRAM#pragma vertex vert#pragma fragment frag#pragma multi_compile_fwdbase#include "UnityCG.cginc"#include "Lighting.cginc"#include "AutoLight.cginc"struct appdata{float4 vertex : POSITION;float2 uv : TEXCOORD0;};struct v2f{float2 uv : TEXCOORD0;float4 pos : SV_POSITION;float3 worldPos : TEXCOORD1;SHADOW_COORDS(2)};sampler2D _MainTex;float4 _MainTex_ST; sampler2D _MaskTex;sampler2D _NoiseTex;float4 _MinMaxPowValue;float4 _NoiseOffsetMultValue; v2f vert (appdata v){v2f o;o.pos = UnityObjectToClipPos(v.vertex);o.uv = TRANSFORM_TEX(v.uv, _MainTex);o.worldPos = mul(unity_ObjectToWorld, v.vertex).xyz;TRANSFER_SHADOW(o)return o;}//常见算法float ClampAndPowValue(float val, float3 minMaxPow){float mValue;mValue = saturate((val - minMaxPow.x)/(minMaxPow.y - minMaxPow.x)); //边缘数值约束在(Min,Max)范围归一化[0,1] (加快或减缓边缘渐变)mValue = saturate(pow(mValue, minMaxPow.z));//提高边缘精度return mValue;}fixed4 frag (v2f i) : SV_Target{fixed4 col = tex2D(_MainTex, i.uv);float4 noise = tex2D(_NoiseTex, i.uv);float gray = noise.r;float2 disOffset = float2(gray - _NoiseOffsetMultValue.x, gray - _NoiseOffsetMultValue.y) * _NoiseOffsetMultValue.z * 0.01;float4 mask = tex2D(_MaskTex, i.uv + disOffset);float r = mask.r;//裁剪边缘精度、边缘渐变幅度控制r = ClampAndPowValue(r, _MinMaxPowValue.xyz);UNITY_LIGHT_ATTENUATION(atten, i, i.worldPos);float a = col.a * r; col = fixed4(col.rgb * atten, a);return col;}ENDCG}}FallBack "Transparent/Cutout/VertexLit" //自带裁剪投影ShadowCaster（保底手段）但我们自己实现了一个ShadowCaster
}
生成遮罩图的脚本，点击Cloud物体（Plane物体）会进行裁剪点击区域四方形格子，透明化。
using System.Collections;
using System.Collections.Generic;
using UnityEngine;[ExecuteInEditMode]
public class GenerateMask : MonoBehaviour
{public int maskWidth;public int maskHeight;private Texture2D maskTexture2D;private Material material;// Start is called before the first frame updatevoid Start(){material = GetComponent<MeshRenderer>().sharedMaterial;Texture2D tempMaskTexture2D = new Texture2D(maskWidth, maskHeight, TextureFormat.ARGB32, false);for (int y = 0; y < maskHeight; y++){for (int x = 0; x < maskWidth; x++){tempMaskTexture2D.SetPixel(x, y, new Color(1, 1, 1, 1)); //默认全遮罩R为1 }}tempMaskTexture2D.Apply();maskTexture2D = tempMaskTexture2D;material.SetTexture("_MaskTex", maskTexture2D);}// Update is called once per framevoid Update(){if (Input.GetMouseButtonDown(0)){Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);RaycastHit hit;if (Physics.Raycast(ray, out hit, 10000, LayerMask.GetMask("Cloud"))){Vector2 uv = hit.textureCoord;Vector2 localPos = new Vector2(uv.x * maskWidth, uv.y * maskHeight);//取整拿到x,yint x = Mathf.FloorToInt(localPos.x);int y = Mathf.FloorToInt(localPos.y);Debug.Log("点击到物体:" + hit.collider.gameObject + ",uv:" + uv + ", 位置:" + localPos + $",(x,y):({x},{y})");maskTexture2D.SetPixel(x, y, new Color(0, 1, 1, 1));maskTexture2D.Apply();}}}
}
投射的阴影距离受这个参数影响
最终版扩展闪烁、消融效果
Shader "Unlit/FogShader"
{Properties{_MainTex ("Texture", 2D) = "white" {}_MaskTex ("裁剪图", 2D) = "white" {}_MinMaxPowValue("边缘渐变范围(x,y),精度系数(z)", vector) = (1,1,1,1)_NoiseTex ("扰动边缘图", 2D) = "white" {}_NoiseOffsetMultValue ("扰动边缘偏移(x,y),扰动幅度(z)", vector) = (0,0,1,1)_Cutoff ("Alpha Cutoff", Range(0,1)) = 0.5 _FlickSpeed ("闪烁速度", float) = 1 _FlickIntensity("闪烁幅度", float) = 1_FlickLevel("闪烁强度", float) = 1_FlickSinMult("闪烁Sin值倍数", float) = 1_FlickSinOffset("闪烁Sin值偏移", float) = 0 _DissolveTex("消融贴图", 2D) = "white" {}_DissolveIntensity("消融幅度", float) = 5}SubShader{ Tags{ "Queue" = "AlphaTest" "IgnoreProjector" = "True" "RenderType" = "TransparentCutout" "DisableBatching" = "True" } Pass{//第一个Pass，让物体可以投射阴影,即把该物体加入到相机的深度纹理的计算中, 并进行裁剪Tags{"LightMode"="ShadowCaster"}ZWrite OnCGPROGRAM#pragma vertex vert#pragma fragment frag#pragma multi_compile_shadercaster#include "UnityCG.cginc"sampler2D _MainTex;float4 _MainTex_ST;sampler2D _MaskTex;float4 _MaskTex_ST;fixed _Cutoff; sampler2D _NoiseTex;float4 _MinMaxPowValue;float4 _NoiseOffsetMultValue; struct v2f {V2F_SHADOW_CASTER;float2 uv:TEXCOORD0;};v2f vert(appdata_base v){v2f o;TRANSFER_SHADOW_CASTER_NORMALOFFSET(o);o.uv= TRANSFORM_TEX(v.texcoord, _MaskTex);return o;}//常见算法float ClampAndPowValue(float val, float3 minMaxPow){float mValue;mValue = saturate((val - minMaxPow.x)/(minMaxPow.y - minMaxPow.x)); //边缘数值约束在(Min,Max)范围归一化[0,1] (加快或减缓边缘渐变)mValue = saturate(pow(mValue, minMaxPow.z));//提高边缘精度return mValue;}float4 frag(v2f i) :SV_Target{//对不透明物体不需要下面两行代码，对使用透明度测试的物体，其完全透明部分不会有阴影，要将其剔除 fixed4 col = tex2D(_MainTex, i.uv);float4 noise = tex2D(_NoiseTex, i.uv);float gray = noise.r;float2 disOffset = float2(gray - _NoiseOffsetMultValue.x, gray - _NoiseOffsetMultValue.y) * _NoiseOffsetMultValue.z * 0.01;float4 mask = tex2D(_MaskTex, i.uv + disOffset);float r = mask.r;//裁剪边缘精度、边缘渐变幅度控制r = ClampAndPowValue(r, _MinMaxPowValue.xyz);r = col.a * r;clip(r - _Cutoff); SHADOW_CASTER_FRAGMENT(i)}ENDCG}Pass{Tags{"LightMode" = "ForwardBase"}ZWrite OffBlend SrcAlpha OneMinusSrcAlpha Cull OffCGPROGRAM#pragma vertex vert#pragma fragment frag#pragma multi_compile_fwdbase#include "UnityCG.cginc"#include "Lighting.cginc"#include "AutoLight.cginc"struct appdata{float4 vertex : POSITION;float2 uv : TEXCOORD0;};struct v2f{float2 uv : TEXCOORD0;float4 pos : SV_POSITION;float3 worldPos : TEXCOORD1;SHADOW_COORDS(2)};sampler2D _MainTex;float4 _MainTex_ST; sampler2D _MaskTex;sampler2D _NoiseTex;float4 _MinMaxPowValue;float4 _NoiseOffsetMultValue; float _FlickSpeed;float _FlickIntensity;float _FlickLevel;sampler2D _DissolveTex;float _FlickSinMult;float _FlickSinOffset;float _DissolveIntensity;v2f vert (appdata v){v2f o;o.pos = UnityObjectToClipPos(v.vertex);o.uv = TRANSFORM_TEX(v.uv, _MainTex);o.worldPos = mul(unity_ObjectToWorld, v.vertex).xyz;TRANSFER_SHADOW(o)return o;}//常见算法float ClampAndPowValue(float val, float3 minMaxPow){float mValue;mValue = saturate((val - minMaxPow.x)/(minMaxPow.y - minMaxPow.x)); //边缘数值约束在(Min,Max)范围归一化[0,1] (加快或减缓边缘渐变)mValue = saturate(pow(mValue, minMaxPow.z));//提高边缘精度return mValue;}float DissolveMaskR(float r, float b, float2 dissolveUV){float dissolve = tex2D(_DissolveTex, dissolveUV).r;float maskR = lerp(r * smoothstep(0, saturate(dissolve * b) + _DissolveIntensity, b), r, b);return maskR;}fixed4 frag (v2f i) : SV_Target{fixed4 col = tex2D(_MainTex, i.uv);float4 noise = tex2D(_NoiseTex, i.uv);float gray = noise.r;float2 disOffset = float2(gray - _NoiseOffsetMultValue.x, gray - _NoiseOffsetMultValue.y) * _NoiseOffsetMultValue.z * 0.01;float4 mask = tex2D(_MaskTex, i.uv + disOffset);float r = mask.r;//裁剪边缘精度、边缘渐变幅度控制r = ClampAndPowValue(r, _MinMaxPowValue.xyz);//使用B通道进行消融R值r = DissolveMaskR(r, mask.b, i.uv);//使用G通道进行闪烁效果//float flicker = lerp(1, sin(_Time.z * _FlickSpeed) * _FlickSinMult + _FlickSinOffset, _FlickIntensity);//第一种方式float flicker = sin(_Time.z * _FlickSpeed) * _FlickSinMult + _FlickSinOffset; //第二种方式比较好控制col.rgb += col.rgb * flicker * mask.g * _FlickLevel;UNITY_LIGHT_ATTENUATION(atten, i, i.worldPos);float a = col.a * r; col = fixed4(col.rgb, a);return col;}ENDCG}}FallBack "Transparent/Cutout/VertexLit" //自带裁剪投影ShadowCaster（保底手段）但我们自己实现了一个ShadowCaster
}
using System.Collections;
using System.Collections.Generic;
using UnityEngine;[ExecuteInEditMode]
public class GenerateMask : MonoBehaviour
{public enum MaskState{None,Sharking,Dissolving,}public int maskWidth;public int maskHeight;private Texture2D maskTexture2D;private Material material;public float sharkTime = 2;public MaskState state = MaskState.None;private float timer;private int cacheX;private int cacheY;public float dissolveSpeed = 1;public float dissolve;// Start is called before the first frame updatevoid Start(){material = GetComponent<MeshRenderer>().sharedMaterial;Texture2D tempMaskTexture2D = new Texture2D(maskWidth, maskHeight, TextureFormat.ARGB32, false);for (int y = 0; y < maskHeight; y++){for (int x = 0; x < maskWidth; x++){tempMaskTexture2D.SetPixel(x, y, new Color(1, 0, 1, 1)); //默认全遮罩R为1 G为0（不闪烁) B为1（不消融)}}tempMaskTexture2D.Apply();maskTexture2D = tempMaskTexture2D;material.SetTexture("_MaskTex", maskTexture2D);}// Update is called once per framevoid Update(){if (state == MaskState.None && Input.GetMouseButtonDown(0)){Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);RaycastHit hit;if (Physics.Raycast(ray, out hit, 10000, LayerMask.GetMask("Cloud"))){Vector2 uv = hit.textureCoord;Vector2 localPos = new Vector2(uv.x * maskWidth, uv.y * maskHeight);//取整拿到x,yint x = Mathf.FloorToInt(localPos.x);int y = Mathf.FloorToInt(localPos.y);//开始闪烁state = MaskState.Sharking;timer = 0;cacheX = x;cacheY = y;Debug.Log("点击到物体:" + hit.collider.gameObject + ",uv:" + uv + ", 位置:" + localPos + $",(x,y):({x},{y})");maskTexture2D.SetPixel(x, y, new Color(1, 1, 1, 1));maskTexture2D.Apply();}}else if (state == MaskState.Sharking){timer += Time.deltaTime;if (timer >= sharkTime){timer = 0;dissolve = 1;state = MaskState.Dissolving;maskTexture2D.SetPixel(cacheX, cacheY, new Color(1, 0, 1, 1));maskTexture2D.Apply();}}else if (state == MaskState.Dissolving){if (dissolve == 0){state = MaskState.None;timer = 0;dissolve = 1;maskTexture2D.SetPixel(cacheX, cacheY, new Color(0, 0, 1, 1));maskTexture2D.Apply();}else{dissolve -= dissolveSpeed * Time.deltaTime;dissolve = Mathf.Max(0, dissolve);maskTexture2D.SetPixel(cacheX, cacheY, new Color(1, 0, dissolve, 1));maskTexture2D.Apply();}}}
}
