第十一章 顶点动画-河流

内置渲染管线

Shader "SunY/C11-Water"
{
    Properties
    {
        _MainTex("Main Tex", 2D) = "white"{}
        _Color("Color Tint", Color) = (1, 1, 1, 1)
        _Magnitude("Distortion Magnitude", float) = 1
        _Frequency("Distortion Frequency", float) = 1
        _InvWaveLength("Distortion Inverse Wave Length", float) = 10
        _Speed("Speed", float) = 0.5
    }

    SubShader
    {
        Tags { "Queue" = "Transparent" "IgnoreProjector" = "True" "RenderType" = "Transparent" "DissableBathing" = "True" }

        Pass
        {
            Tags { "LightMode" = "ForwardBase" }

            ZWrite Off
            Blend SrcAlpha OneMinusSrcAlpha
            Cull Off

            CGPROGRAM

            #include "UnityCG.cginc"

            #pragma vertex vert
            #pragma fragment frag

            sampler2D _MainTex;
            float4 _MainTex_ST;
            fixed4 _Color;
            float _Magnitude;
            float _Frequency;
            float _InvWaveLength;
            float _Speed;

            struct a2v
            {
                float4 vertex : POSITION;
                float4 texcoord : TEXCOORD0;
            };

            struct v2f
            {
                float4 pos : SV_POSITION;
                float2 uv : TEXCOORD0;
            };

            v2f vert(a2v v)
            {
                 v2f o;

                // 计算一个面的正弦，只需要用顶点的一个轴计算偏移就行了
                float x = sin(_Frequency * _Time.y + v.vertex.z * _InvWaveLength) * _Magnitude;
                v.vertex.x += x;

                // 计算二维水面的波浪
                // float z = sin(_Frequency * _Time.y + (v.vertex.x + vertex.y) * _InvWaveLength) * _Magnitude;
                // v.vertex.z += z;

                o.pos = UnityObjectToClipPos(v.vertex);
                
                o.uv = TRANSFORM_TEX(v.texcoord, _MainTex);
                o.uv.y +=  _Time.y * _Speed;

                return o;
            }

            fixed4 frag(v2f i) : SV_Target
            {
                fixed4 color = tex2D(_MainTex, i.uv);
                color.rgb *= _Color.rgb;

                return color;
            }

            ENDCG
        }
    }

    FallBack "Transparent/VertexLit"
}

URP渲染管线

Shader "SunY/C11-U-Water"
{
    Properties
    {
       _MainTex("Main Tex", 2D) = "white"{}
       _Color("Color Tint", Color) = (1, 1, 1, 1)
       _Magnitude("Distortion Magnitude", float) = 1
       _Frequency("Distortion Frequency", float) = 1
       _InvWaveLength("Distortion Inverse Wave Length", float) = 10
       _Speed("Speed", float) = 0.5
    }

    SubShader
    {
       Tags { "Queue" = "Transparent" "IgnorProjector" = "True" "RenderType" = "Transparent" "DissableBathing" = "True" "RenderPipeline" = "UniversalPipeline" }

       Pass
       {
              Tags { "LightMode" = "UniversalForward" }
              ZWrite Off
              Blend SrcAlpha OneMinusSrcAlpha
              Cull Off

              HLSLPROGRAM

              #include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"

              #pragma vertex vert
              #pragma fragment frag

              CBUFFER_START(UnityPerMaterial)
              float4 _MainTex_ST;
              half4 _Color;
              float _Magnitude;
              float _Frequency;
              float _InvWaveLength;
              float _Speed;
              CBUFFER_END

              TEXTURE2D(_MainTex);
              SAMPLER(sampler_MainTex);

              struct a2v
              {
                    float4 vertex : POSITION;
                    float4 texcoord : TEXCOORD0;
              };

              struct v2f
              {
                    float4 pos : SV_POSITION;
                    float2 uv : TEXCOORD0;
              };

              v2f vert(a2v v)
              {
                    v2f o;

                    float x = sin(_Frequency * _Time.y + v.vertex.z * _InvWaveLength) * _Magnitude;
                    v.vertex.x += x;
                    o.pos = TransformObjectToHClip(v.vertex);

                    o.uv = TRANSFORM_TEX(v.texcoord, _MainTex);
                    o.uv.y += _Time.y * _Speed;

                    return o;
              }

              half4 frag(v2f i) : SV_Target
              {
                    half4 color = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, i.uv);
                    color.rgb *= _Color.rgb;

                    return color;
              }

              ENDHLSL
       }
    }
}