[游戏开发]Unity 水墨风格Shader

最近在做一个帮助美术初学者画稿定位的一个项目，里面涉及到了一些要把图片变成水墨风格的一个需求，查阅资料，在前人的基础上修修改改，弄出了一个Shader，效果如下

效果就是可以切换水墨画风格和原画，还可以调整线条的粗细和内容的填充度，具体参数如下

shader代码如下：

Shader "Custom/SobelLine"
{
    Properties
    {
        _MainTex ("Base (RGB)", 2D) = "white" {}
		//_MainTex ("Base (RGB)", 2D) = "white" {}
		_Saturability ("_Saturability",Range(0.0,2.0))= 0.5
		_LineRange ("_LineRange", Range(0, 1.6)) = 0.8
		_ScreenResolution ("_ScreenResolution", Vector) = (0,0,0,0)
    }
    SubShader
    {
        Tags { "RenderType"="Opaque" }
        LOD 100

        Pass
        {
            Cull Off ZWrite Off ZTest Always
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			#pragma multi_compile MY_multi_Y MY_multi_N
			#include "UnityCG.cginc"
			
			uniform sampler2D _MainTex;
			uniform float _Saturability;
			uniform float _LineRange;
			uniform float4 _ScreenResolution;
			

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

            struct v2f
            {
                float2 uv : TEXCOORD0;
                UNITY_FOG_COORDS(1)
                float4 vertex : SV_POSITION;

				float4 color    : COLOR;
            };

			 v2f vert (appdata v)
            {
                v2f o;
                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = TRANSFORM_TEX(v.uv, _MainTex);
                UNITY_TRANSFER_FOG(o,o.vertex);
				#if _TEX_ON
					v2f OUT;
					OUT.vertex = UnityObjectToClipPos(v.vertex);
					OUT.uv = v.uv;
					OUT.color = v.color;
					return OUT;
				#endif

                return o;
            }

			float intensity(in float4 color){
				return sqrt((color.x*color.x)+(color.y*color.y)+(color.z*color.z));
			}
				
			float3 sobel(float stepx, float stepy, float2 center){
				
				float tleft 	= intensity(tex2D(_MainTex,center + float2(-stepx,stepy)*_LineRange));
				float left 		= intensity(tex2D(_MainTex,center + float2(-stepx,0)*_LineRange));
				float bleft 	= intensity(tex2D(_MainTex,center + float2(-stepx,-stepy)*_LineRange));
				float top 		= intensity(tex2D(_MainTex,center + float2(0,stepy)*_LineRange));
				float bottom 	= intensity(tex2D(_MainTex,center + float2(0,-stepy)*_LineRange));
				float tright 	= intensity(tex2D(_MainTex,center + float2(stepx,stepy)*_LineRange));
				float right 	= intensity(tex2D(_MainTex,center + float2(stepx,0)*_LineRange));
				float bright 	= intensity(tex2D(_MainTex,center + float2(stepx,-stepy)*_LineRange));
				
				float x =  tleft + 2.0 * left + bleft  - tright - 2.0 * right  - bright;
				float y = -tleft - 2.0 * top  - tright + bleft  + 2.0 * bottom + bright;
				
				float color = sqrt((x*x) + (y*y));
				if(color<_Saturability)
				{
				    color=0;
				}
				return float3(1- color,1- color,1- color);
			}            

			           

            fixed4 frag (v2f i) : SV_Target
            {

				float4 col = float4(0, 0, 0, 0);


				#ifdef MY_multi_Y
					col = tex2D(_MainTex, i.uv);
                // apply fog
					UNITY_APPLY_FOG(i.fogCoord, col);
				#endif
				#ifdef MY_multi_N
					float2 uvst = UnityStereoScreenSpaceUVAdjust(i.uv, _MainTex_ST);
					col= float4(sobel(1./_ScreenResolution.x, 1./_ScreenResolution.y, uvst),1.0);	
				#endif

				return col;
				
            }
            ENDCG
        }
    }
}

值得注意的是，在原话和水墨风格切换的时候我是通过两个变体处理的
然后C#脚本里面进行切换

 		if (Input.GetKeyDown(KeyCode.W))
        {

            Shader.EnableKeyword("MY_multi_Y");
            Shader.DisableKeyword("MY_multi_N");


        }

        if (Input.GetKeyDown(KeyCode.A))
        {

            Shader.EnableKeyword("MY_multi_N");
            Shader.DisableKeyword("MY_multi_Y");

        }

代码一共就这么多，需要复制粘贴一下就行，或者私信向我要也ok，快下班了，时间仓促，就这样，有时间我在补充补充放个工程上去，哈哈哈