unity 写一个水墨效果shader

下面是一个简单的水墨效果Shader的示例： ```shader Shader "Custom/Watercolor" { Properties { _MainTex ("Texture", 2D) = "white" {} _EdgeDarkness ("Edge Darkness", Range(0, 1)) = 0.1 _InkAmount ("Ink Amount", Range(0, 1)) = 0.5 _InkDensity ("Ink Density", Range(0, 1)) = 0.5 _InkSpread ("Ink Spread", Range(0, 1)) = 0.5 } SubShader { Tags { "RenderType"="Opaque" } LOD 100 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 _EdgeDarkness; float _InkAmount; float _InkDensity; float _InkSpread; v2f vert (appdata v) { v2f o; o.vertex = UnityObjectToClipPos(v.vertex); o.uv = v.uv; return o; } fixed4 frag (v2f i) : SV_Target { float4 color = tex2D(_MainTex, i.uv); // Edge Detection float3 sobel_x = float3(-1, 0, 1); float3 sobel_y = float3(-1, 0, 1); float4 edge = 1 - length(tex2D(_MainTex, i.uv + sobel_x.xy * _ScreenParams.zw)) + length(tex2D(_MainTex, i.uv + sobel_x.zy * _ScreenParams.zw)) + length(tex2D(_MainTex, i.uv + sobel_y.xy * _ScreenParams.zw)) - length(tex2D(_MainTex, i.uv + sobel_y.zy * _ScreenParams.zw)); // Ink effect float ink = saturate((_InkDensity + _InkSpread) - length(edge.rgb) * _InkSpread); color = lerp(color, float4(0, 0, 0, 1), ink * _InkAmount); // Edge darkness float edgeDarkness = saturate((_EdgeDarkness * 2.0 - length(edge.rgb)) * 10.0); color.rgb = lerp(color.rgb, float3(0, 0, 0), edgeDarkness); return color; } ENDCG } } FallBack "Diffuse" } ``` 这个Shader包括了边缘检测、水墨效果和边缘加深三个特效。你可以在Shader中调整参数来达到不同的效果。