Shader例項:2D流光

準備：
1.一張背景圖
2.一張流光圖
3.一張過濾圖

like this：

效果：

程式碼：

複製程式碼
Shader “Custom/2d_flow”
{
Properties
{
_MainTex(“main tex”,2d) = “”{}//主貼圖
_FlowTex(“flow tex”,2d) = “”{}//流光圖
_MaskTex(“mask tex”,2d) = “”{}//過濾圖
_FlowSpeed(“speed”, Range(0,1)) = 1.0//流光移動速度
}

SubShader
{
    Pass
    {
        CGPROGRAM
        #pragma vertex vert
        #pragma fragment frag
        #include"UnityCG.cginc"

        sampler2D _MainTex;
        sampler2D _FlowTex;
        sampler2D _MaskTex;
        float _FlowSpeed;

        struct v2f
        {
            float4 vertex:POSITION;
            float4 uv:TEXCOORD0;
        };

        v2f vert(appdata_base v)
        {
            v2f o;
            o.vertex = mul(UNITY_MATRIX_MVP, v.vertex);
            o.uv = v.texcoord;
            return o;
        }

        half4 frag(v2f IN):COLOR
        {
            //取樣主貼圖
            half4 c = tex2D(_MainTex,IN.uv);

            //流光uv移動
            half2 flow_uv = half2(IN.uv.x / 2,IN.uv.y);
            flow_uv.x += -_FlowSpeed * _Time.w;
            half4 flow = tex2D(_FlowTex, flow_uv);
            flow.rgb *= half3(1,1,0);

            //根據過濾圖的alpha值，將流光效果限制在文字上
            half4 mask = tex2D(_MaskTex,IN.uv);
            if (mask.a == 1)
            {
                c.rgb /= 1.5;
                c.rgb += flow.rgb;
            }
            return c;
        }
        ENDCG
    }
}
FallBack "Diffuse"
 

}