SpriteShader备注——UV乒乓动画效果

效果：

//////////////////////////////////////////////
/// 2DxFX v3 - by VETASOFT 2018 //
//////////////////////////////////////////////


//////////////////////////////////////////////

Shader "2DxFX_Extra_Shaders/Animated_PingPong"
{
    Properties
    {
        [PerRendererData] _MainTex("Sprite Texture", 2D) = "white" {}
        //乒乓动画偏移UV_X
        AnimatedPingPongOffsetUV_1_OffsetX_1("AnimatedPingPongOffsetUV_1_OffsetX_1", Range(-1, 1)) = 0.182
        //乒乓动画偏移UV_Y
        AnimatedPingPongOffsetUV_1_OffsetY_1("AnimatedPingPongOffsetUV_1_OffsetY_1", Range(-1, 1)) = 0
        //乒乓动画缩放UV_X
        AnimatedPingPongOffsetUV_1_ZoomX_1("AnimatedPingPongOffsetUV_1_ZoomX_1", Range(1, 10)) = 1
        //乒乓动画缩放UV_Y
        AnimatedPingPongOffsetUV_1_ZoomY_1("AnimatedPingPongOffsetUV_1_ZoomY_1", Range(1, 10)) = 1
        //乒乓动画速度
        AnimatedPingPongOffsetUV_1_Speed_1("AnimatedPingPongOffsetUV_1_Speed_1", Range(-1, 1)) = 0.354
        //UV 插值
        _LerpUV_Fade_1("_LerpUV_Fade_1", Range(0, 1)) = 1
        //UV 渐淡
        _SpriteFade("SpriteFade", Range(0, 1)) = 1.0

        // required for UI.Mask
        [HideInInspector]_StencilComp("Stencil Comparison", Float) = 8
        [HideInInspector]_Stencil("Stencil ID", Float) = 0
        [HideInInspector]_StencilOp("Stencil Operation", Float) = 0
        [HideInInspector]_StencilWriteMask("Stencil Write Mask", Float) = 255
        [HideInInspector]_StencilReadMask("Stencil Read Mask", Float) = 255
        [HideInInspector]_ColorMask("Color Mask", Float) = 15

    }

    SubShader
    {
        // 渲染队列=透明通道            忽略投影                    渲染类型                    预览类型=面板         可以使用精灵图吗
        Tags {"Queue" = "Transparent" "IgnoreProjector" = "true" "RenderType" = "Transparent" "PreviewType"="Plane" "CanUseSpriteAtlas"="True" }
        //深度缓存      透明度混合                   背面渲染剔除
        ZWrite Off Blend SrcAlpha OneMinusSrcAlpha Cull Off

        // required for UI.Mask
        Stencil
        {
        Ref [_Stencil]
        Comp [_StencilComp]
        Pass [_StencilOp]
        ReadMask [_StencilReadMask]
        WriteMask [_StencilWriteMask]
        }

        Pass
        {

            CGPROGRAM
            //声明顶点着色器代码块
            #pragma vertex vert
            //声明片元着色器代码块
            #pragma fragment frag
            //使用低精度渲染
            #pragma fragmentoption ARB_precision_hint_fastest
            #include "UnityCG.cginc"

            struct appdata_t{
                float4 vertex   : POSITION;//顶点位置信息
                float4 color    : COLOR;//颜色信息
                float2 texcoord : TEXCOORD0;//纹理坐标集
            };

            struct v2f
            {
                float2 texcoord  : TEXCOORD0;//纹理坐标集
                float4 vertex   : SV_POSITION;//屏幕位置信息
                float4 color    : COLOR;//颜色信息
            };

            //对应上面材质属性
            sampler2D _MainTex;
            float _SpriteFade;
            float AnimatedPingPongOffsetUV_1_OffsetX_1;
            float AnimatedPingPongOffsetUV_1_OffsetY_1;
            float AnimatedPingPongOffsetUV_1_ZoomX_1;
            float AnimatedPingPongOffsetUV_1_ZoomY_1;
            float AnimatedPingPongOffsetUV_1_Speed_1;
            float _LerpUV_Fade_1;

            //顶点着色器代码块
            v2f vert(appdata_t IN)
            {
                v2f OUT;
                OUT.vertex = UnityObjectToClipPos(IN.vertex);//从模型空间转换到裁剪空间
                OUT.texcoord = IN.texcoord;//纹理坐标集
                OUT.color = IN.color;//颜色
                return OUT;
            }

            //New！ 乒乓动画偏移UV
            float2 AnimatedPingPongOffsetUV(float2 uv, float offsetx, float offsety, float zoomx, float zoomy, float speed)
            {
                //用sin函数获取到一个正玄曲线，乒乓的动画就是根据这个曲线来的
                float time = sin(_Time * 100* speed)  * 0.1;
                speed *= time * 25;
                
                //对UV坐标进行偏移
                uv += float2(offsetx, offsety)*speed;
                
                //对UV进行缩放
                uv = uv * float2(zoomx, zoomy);
                
                return uv;
            }

            //片元着色器代码块
            float4 frag (v2f i) : COLOR
            {
                //乒乓动画偏移UV
                float2 AnimatedPingPongOffsetUV_1 = AnimatedPingPongOffsetUV(i.texcoord,AnimatedPingPongOffsetUV_1_OffsetX_1,AnimatedPingPongOffsetUV_1_OffsetY_1,AnimatedPingPongOffsetUV_1_ZoomX_1,AnimatedPingPongOffsetUV_1_ZoomY_1,AnimatedPingPongOffsetUV_1_Speed_1);
                
                //UV插值(这里插值可以矫正前面缩放比和动画速度，原理上就是让处理后的UV更接近处理前的UV)
                i.texcoord = lerp(i.texcoord,AnimatedPingPongOffsetUV_1,_LerpUV_Fade_1);
                //纹理采样
                float4 _MainTex_1 = tex2D(_MainTex,i.texcoord);
                //声明最终结果
                float4 FinalResult = _MainTex_1;
                FinalResult.rgb *= i.color.rgb;
                //对透明通道进行渐淡处理
                FinalResult.a = FinalResult.a * _SpriteFade * i.color.a;
                
                return FinalResult;
            }

            ENDCG
        }
    }
    Fallback "Sprites/Default"
}