本文实例为大家分享了UnityShader3实现2D描边效果的具体代码，供大家参考，具体内容如下

1.

Shader "Custom/Edge"{ Properties { _MainTex ("Texture", 2D) = "white" {} _OffsetUV ("OffsetUV", Range(0, 1)) = 0.1 _EdgeColor ("EdgeColor", Color) = (1, 0, 0, 1) _AlphaTreshold ("Treshold", Range(0, 1)) = 0.5 } SubShader { Tags { "Queue" = "Transparent" } Blend SrcAlpha OneMinusSrcAlpha Pass { CGPROGRAM #pragma vertex vert #pragma fragment frag #include "UnityCG.cginc" struct appdata { float4 vertex : POSITION; fixed2 uv : TEXCOORD0; }; struct v2f { float4 vertex : SV_POSITION; fixed2 uv[5] : TEXCOORD0; }; sampler2D _MainTex; float4 _MainTex_ST; fixed _OffsetUV; fixed4 _EdgeColor; fixed _AlphaTreshold; v2f vert (appdata v) { v2f o; o.vertex = mul(UNITY_MATRIX_MVP, v.vertex); o.uv[0] = v.uv; o.uv[1] = v.uv + fixed2(0, _OffsetUV); //up o.uv[2] = v.uv + fixed2(-_OffsetUV, 0); //left o.uv[3] = v.uv + fixed2(0, -_OffsetUV); //bottom o.uv[4] = v.uv + fixed2(_OffsetUV, 0); //right return o; } fixed4 frag (v2f i) : SV_Target { fixed4 original = tex2D(_MainTex, i.uv[0]); fixed alpha = original.a; fixed p1 = tex2D(_MainTex, i.uv[1]).a; fixed p2 = tex2D(_MainTex, i.uv[2]).a; fixed p3 = tex2D(_MainTex, i.uv[3]).a; fixed p4 = tex2D(_MainTex, i.uv[4]).a; alpha = p1 + p2 + p3 + p4 + alpha; alpha /= 5; if (alpha < _AlphaTreshold) original.rgb = _EdgeColor.rgb; return original; } ENDCG } }}

2.

Shader "Custom/Edge"{ Properties { _Edge ("Edge", Range(0, 0.2)) = 0.043 _EdgeColor ("EdgeColor", Color) = (1, 1, 1, 1) _MainTex ("MainTex", 2D) = "white" {} } SubShader { Pass { CGPROGRAM #pragma vertex vert #pragma fragment frag #include "UnityCG.cginc" fixed _Edge; fixed4 _EdgeColor; sampler2D _MainTex; struct appdata { float4 vertex : POSITION; fixed2 uv : TEXCOORD0; }; struct v2f { float4 vertex : SV_POSITION; float4 objVertex : TEXCOORD0; fixed2 uv : TEXCOORD1; }; v2f vert (appdata v) { v2f o; o.vertex = mul(UNITY_MATRIX_MVP, v.vertex); o.objVertex = v.vertex; o.uv = v.uv; return o; } fixed4 frag (v2f i) : SV_Target { fixed x = i.uv.x; fixed y = i.uv.y; if((x < _Edge) || (abs(1 - x) < _Edge) || (y < _Edge) || (abs(1 - y) < _Edge)) { return _EdgeColor * abs(cos(_Time.y)); } else { fixed4 color = tex2D(_MainTex, i.uv); return color; } //return i.objVertex; //return fixed4(i.uv, 0, 1); } ENDCG } }}

3.如下图，左边是一个Image，右边是一个Plane。

// Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with 'UnityObjectToClipPos(*)' Shader "Custom/Edge" { Properties { _Edge ("Edge", Range(0, 0.2)) = 0.043 _EdgeColor ("EdgeColor", Color) = (1, 1, 1, 1) _FlowColor ("FlowColor", Color) = (1, 1, 1, 1) _FlowSpeed ("FlowSpeed", Range(0, 10)) = 3 _MainTex ("MainTex", 2D) = "white" {} } SubShader { Tags { "Queue"="Transparent" "RenderType"="Transparent" "IgnoreProjector"="True" } Pass { ZWrite Off Blend SrcAlpha OneMinusSrcAlpha CGPROGRAM #pragma vertex vert #pragma fragment frag #include "UnityCG.cginc" fixed _Edge; fixed4 _EdgeColor; fixed4 _FlowColor; float _FlowSpeed; sampler2D _MainTex; struct appdata { float4 vertex : POSITION; fixed2 uv : TEXCOORD0; }; struct v2f { float4 vertex : SV_POSITION; fixed2 uv : TEXCOORD1; }; v2f vert (appdata v) { v2f o; o.vertex = UnityObjectToClipPos(v.vertex); o.uv = v.uv; return o; } fixed4 frag (v2f i) : SV_Target { fixed x = i.uv.x; fixed y = i.uv.y; if((x < _Edge) || (abs(1 - x) < _Edge) || (y < _Edge) || (abs(1 - y) < _Edge)) { //点旋转公式： //假设对图片上任意点(x,y)，绕一个坐标点(rx0,ry0)逆时针旋转a角度后的新的坐标设为(x0,y0)，有公式： //x0 = (x - rx0) * cos(a) - (y - ry0) * sin(a) + rx0 ; //y0 = (x - rx0) * sin(a) + (y - ry0) * cos(a) + ry0 ; float a = _Time.y * _FlowSpeed; float2 rotUV; x -= 0.5; y -= 0.5; rotUV.x = x * cos(a) - y * sin(a) + 0.5; rotUV.y = x * sin(a) + y * cos(a) + 0.5; fixed temp = saturate(rotUV.x - 0.5);//-0.5作用是调整流动颜色的比例 return _EdgeColor * (1 - temp) + _FlowColor * temp; } else { //fixed4 color = tex2D(_MainTex, i.uv); return fixed4(1, 1, 1, 0); } } ENDCG } } }

4.通过观察上面的效果图，会发现右边的Plane出现了锯齿。而解决锯齿一般的方法就是做模糊处理，模糊处理一般又有贴图处理和代码处理之分，这里使用的是贴图处理。贴图处理需要提供一张边界模糊的贴图。

如上图，左下是内边反锯齿的图，右上是未经处理的图。

// Upgrade NOTE: replaced 'mul(UNITY_MATRIX_MVP,*)' with 'UnityObjectToClipPos(*)' Shader "Custom/Edge2" { Properties { _Edge ("Edge", Range(0, 0.2)) = 0.043 _EdgeColor ("EdgeColor", Color) = (1, 1, 1, 1) _FlowColor ("FlowColor", Color) = (1, 1, 1, 1) _FlowSpeed ("FlowSpeed", Range(0, 10)) = 3 _MainTex ("MainTex", 2D) = "white" {} } SubShader { Tags { "Queue"="Transparent" "RenderType"="Transparent" "IgnoreProjector"="True" } Pass { ZWrite Off Blend SrcAlpha OneMinusSrcAlpha CGPROGRAM #pragma vertex vert #pragma fragment frag #include "UnityCG.cginc" fixed _Edge; fixed4 _EdgeColor; fixed4 _FlowColor; float _FlowSpeed; sampler2D _MainTex; struct appdata { float4 vertex : POSITION; fixed2 uv : TEXCOORD0; }; struct v2f { float4 vertex : SV_POSITION; fixed2 uv : TEXCOORD1; }; v2f vert (appdata v) { v2f o; o.vertex = UnityObjectToClipPos(v.vertex); o.uv = v.uv; return o; } fixed4 frag (v2f i) : SV_Target { fixed4 color = tex2D(_MainTex, i.uv); float alpha = color.a; fixed x = i.uv.x; fixed y = i.uv.y; float a = _Time.y * _FlowSpeed; float2 rotUV; x -= 0.5; y -= 0.5; rotUV.x = x * cos(a) - y * sin(a) + 0.5; rotUV.y = x * sin(a) + y * cos(a) + 0.5; fixed temp = saturate(rotUV.x - 0.5);//-0.5作用是调整流动颜色的比例 fixed4 finalColor = _EdgeColor * (1 - temp) + _FlowColor * temp; finalColor.a = alpha; return finalColor; } ENDCG } } }

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。