[A] wind cloth

Packages/zzwater/shaders/libs/WindAnim.hlsl

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+//UNITY_SHADER_NO_UPGRADE
+#ifndef WIND_ANIM_INCLUDE
+#define WIND_ANIM_INCLUDE
+
+inline float4 SmoothCurve( float4 x ) {
+    return x * x *( 3.0 - 2.0 * x );
+}
+
+inline float4 TriangleWave( float4 x ) {
+    return abs( frac( x + 0.5 ) * 2.0 - 1.0 );
+}
+
+inline float4 SmoothTriangleWave( float4 x ) {
+    return SmoothCurve( TriangleWave( x ) );
+}
+
+
+inline float4 ClothWindAnim(float4 pos, float3 normal, float4 animParams,float4 wind,float2 time)
+{	
+    // animParams.x = branch phase
+    // animParams.y = edge flutter factor
+    // animParams.z = primary factor
+    // animParams.w = secondary factor
+
+
+    float fDetailAmp = 0.1f;
+    float fBranchAmp = 0.3f;
+
+    // Phases (object, vertex, branch)
+    float fObjPhase = dot(unity_ObjectToWorld[3].xyz, 1);
+    float fBranchPhase = fObjPhase + animParams.x;
+
+    float fVtxPhase = dot(pos.xyz, animParams.y + fBranchPhase);
+
+    // x is used for edges; y is used for branches
+    float2 vWavesIn = time  + float2(fVtxPhase, fBranchPhase );
+
+    // 1.975, 0.793, 0.375, 0.193 are good frequencies
+    float4 vWaves = (frac( vWavesIn.xxyy * float4(1.975, 0.793, 0.375, 0.193) ) * 2.0 - 1.0);
+
+    vWaves = SmoothTriangleWave( vWaves );
+    float2 vWavesSum = vWaves.xz + vWaves.yw;
+
+    // Edge (xz) and branch bending (y)
+    float3 bend = animParams.y * fDetailAmp * normal.xyz;
+    bend.y = animParams.w * fBranchAmp;
+    pos.xyz += ((vWavesSum.xyx * bend)*wind.w + (wind.xyz * vWavesSum.y * animParams.w)) * wind.w; 
+
+    // Primary bending
+    // Displace position
+    pos.xyz += animParams.z * wind.xyz;
+
+    return pos;
+}
+
+#endif //WIND_ANIM_INCLUDE 

Packages/zzwater/shaders/libs/WindAnim.hlsl.meta

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+fileFormatVersion: 2
+guid: 418d88a69b1774954ace0d91b8c685d7
+ShaderIncludeImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Packages/zzwater/shaders/wind_cloth.shader

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+Shader "zzwind/WindClothUnlit"
+{
+    
+    Properties
+    {
+
+        [MainTexture] _BaseMap("Texture", 2D) = "white" {}
+        [MainColor] _BaseColor("Color", Color) = (1, 1, 1, 1)
+        _Cutoff("AlphaCutout", Range(0.0, 1.0)) = 0.5
+        _Wind("Wind params",Vector) = (1,1,1,1)
+        _WindAmplitude("Wind Amplitude", float) = 0.5
+        _WindSpeed("Wind Speed",float) = 0.5
+    }
+
+    SubShader
+    {
+        Tags
+        {
+            "RenderType" = "Opaque"
+            "IgnoreProjector" = "True"
+            "UniversalMaterialType" = "Unlit"
+            "RenderPipeline" = "UniversalPipeline"
+        }
+
+        Pass
+        {
+            Name "Unlit"
+			Blend SrcAlpha OneMinusSrcAlpha, One OneMinusSrcAlpha
+            ZWrite On
+            Cull Back
+            ZTest LEqual
+            ZClip On
+
+            HLSLPROGRAM
+
+            #pragma vertex vert
+            #pragma fragment frag
+
+            #include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"
+            #include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Lighting.hlsl"
+			#include "Packages/zzwater/shaders/libs/WindAnim.hlsl"
+
+
+            TEXTURE2D(_BaseMap);
+            SAMPLER(sampler_BaseMap);
+
+            CBUFFER_START(UnityPerMaterial)
+                float _Cutoff;
+                half4 _BaseColor;
+                half4 _BaseMap_ST;
+                half4 _Wind;
+                float _WindAmplitude;
+                float _WindSpeed;
+            CBUFFER_END
+
+            struct Attributes
+            {
+                float4 positionOS : POSITION;
+                float4 tangentOS : TANGENT;
+                float2 uv : TEXCOORD0;
+                float3 normalOS : NORMAL;
+                float4 color : COLOR;
+            };
+
+            struct Varyings
+            {
+                float4 positionCS : SV_POSITION;
+                float2 uv : TEXCOORD0;
+                float4 color : TEXCOORD2;
+            };
+
+            Varyings vert(Attributes input)
+            {
+                Varyings output;
+
+                float bendingFact = input.color.a;
+                float4 wind;
+                wind.xyz = _Wind.xyz;
+                wind.w = _Wind.w * bendingFact.x;
+
+                float4 windParams = float4(0,_WindAmplitude,bendingFact,0);
+                float windTime = _Time.y * _WindSpeed;
+                float4 VertexInWndPos = ClothWindAnim(input.positionOS,input.normalOS,windParams,wind,windTime);
+
+                output.positionCS = TransformObjectToHClip(VertexInWndPos);
+                output.uv = TRANSFORM_TEX(input.uv, _BaseMap);
+                output.color = input.color;
+                return output;
+            }
+
+            float4 frag(Varyings input) : SV_Target
+            {
+                half2 uv = input.uv;
+                half4 texColor = SAMPLE_TEXTURE2D(_BaseMap, sampler_BaseMap, uv);
+                half3 color = texColor.rgb * _BaseColor.rgb;
+                half alpha = texColor.a * _BaseColor.a;
+                clip(alpha - _Cutoff);
+
+                return float4(color, alpha);
+            }
+
+            ENDHLSL
+        }
+    }
+}

Packages/zzwater/shaders/wind_cloth.shader.meta

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+  nonModifiableTextures: []
+  userData: 
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