Unity Shader unity文档学习笔记(十八)：unity雾效原理

看很多文章用近平面远平面组成矩阵后转到裁剪空间下通过Z值来解，实际更简单的方式可以直接通过判断距离来实现

FogMgr控制远近面

public class TestFog : MonoBehaviour
{public int startDis = 0;public int endDis = 50;public Vector4 fogParam;public void Awake(){fogParam = new Vector4(startDis, endDis, 0, 0);Shader.SetGlobalVector("DisFog", fogParam);}
}

Test_Fog.cginc 库

#ifndef TEST_FOG
#define TEST_FOGfloat4 DisFog;float MyComputerFog(float3 worldPos)
{float fogFactory = distance(worldPos.xz, _WorldSpaceCameraPos.xz)/(DisFog.y - DisFog.x);return fogFactory;
}#endif

TestFog shader

Shader "Test/TestFog"
{Properties{_MainTex ("Texture", 2D) = "white" {}_FogColor ("FogColor", Color) = (1, 1, 1, 1)}SubShader{Tags { "RenderType"="Opaque" }LOD 100Pass{CGPROGRAM#pragma vertex vert#pragma fragment frag#include "UnityCG.cginc"#include "Test_Fog.cginc"struct appdata{float4 vertex : POSITION;float2 uv : TEXCOORD0;};struct v2f{float2 uv : TEXCOORD0;float3 worldPos : TEXCOORD1;float4 vertex : SV_POSITION;};sampler2D _MainTex;float4 _MainTex_ST;float4 _FogColor;v2f vert (appdata v){v2f o;o.vertex = UnityObjectToClipPos(v.vertex);o.uv = TRANSFORM_TEX(v.uv, _MainTex);o.worldPos = mul(unity_ObjectToWorld, v.vertex).xyz;return o;}fixed4 frag (v2f i) : SV_Target{// sample the texturefixed4 col = tex2D(_MainTex, i.uv);fixed4 fogColor = _FogColor * MyComputerFog(i.worldPos);return lerp(col, fogColor, 0.5);}ENDCG}}
}

效果