Unity URP高度雾效果Shader

实现原理

见这篇文章Unity Shader-深度相关知识总结与效果实现（LinearDepth，Reverse Z，世界坐标重建，软粒子，高度雾，运动模糊，扫描线效果）_puppet_master的专栏-CSDN博客_shader深度

核心Shader代码


Shader "Universal Render Pipeline/Dejavu/HeightFog"
{Properties{_MainTex("Base (RGB)", 2D) = "white" {}[HDR]_FogColor("_FogColor (default = 1,1,1,1)", color) = (1,1,1,1)}HLSLINCLUDE
#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"CBUFFER_START(UnityPerMaterial)float4 _MainTex_ST;half4 _FogColor;float _FogStartHeight;float _FogHeight;float _FogIntensity;CBUFFER_END//TEXTURE2D(_MainTex);//SAMPLER(sampler_MainTex);sampler2D _MainTex;TEXTURE2D(_CameraDepthTexture);SAMPLER(sampler_CameraDepthTexture);struct appdata {float4 positionOS : POSITION;float2 uv : TEXCOORD0;UNITY_VERTEX_INPUT_INSTANCE_ID};struct v2f {float4 positionCS : SV_POSITION;float2 uv : TEXCOORD0;float3 viewRayWorld : TEXCOORD1;UNITY_VERTEX_OUTPUT_STEREO};//vertex shaderv2f vert(appdata v){v2f o;UNITY_SETUP_INSTANCE_ID(v);UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);o.positionCS = TransformObjectToHClip(v.positionOS.xyz);float sceneRawDepth = 1;#if defined(UNITY_REVERSED_Z)sceneRawDepth = 1 - sceneRawDepth;
#endiffloat3 worldPos = ComputeWorldSpacePosition(v.uv, sceneRawDepth, UNITY_MATRIX_I_VP);o.viewRayWorld = worldPos - _WorldSpaceCameraPos.xyz;o.uv = v.uv;return o;}//fragment shaderfloat4 frag(v2f i) : SV_Target{float sceneRawDepth = SAMPLE_DEPTH_TEXTURE(_CameraDepthTexture, sampler_CameraDepthTexture, i.uv);float linear01Depth = Linear01Depth(sceneRawDepth, _ZBufferParams);float3 worldPos = _WorldSpaceCameraPos.xyz + ( linear01Depth) * i.viewRayWorld;float blendParam  = saturate((_FogStartHeight - worldPos.y) / _FogHeight);blendParam = max(linear01Depth * _FogHeight, blendParam);half4 screenCol =  tex2D(_MainTex,  i.uv);return lerp(screenCol, _FogColor, blendParam * _FogIntensity);}ENDHLSL//开始SubShaderSubShader{//Tags {"RenderType" = "Opaque"  "RenderPipeline" = "UniversalPipeline"}Tags{ "RenderPipeline" = "UniversalPipeline"  "RenderType" = "Overlay" "Queue" = "Transparent-499" "DisableBatching" = "True" }LOD 100ZTest Always Cull Off ZWrite OffBlend one zeroPass{Name "HeightFog"//后处理效果一般都是这几个状态//使用上面定义的vertex和fragment shaderHLSLPROGRAM#pragma vertex vert#pragma fragment fragENDHLSL}}//后处理效果一般不给fallback，如果不支持，不显示后处理即可
}