[A] wind Test shader

Assets/Test/test/WindAnim.hlsl

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+//UNITY_SHADER_NO_UPGRADE
+#ifndef WIND_ANIM
+#define WIND_ANIM
+
+// SmoothTriangleWave function
+inline float SmoothTriangleWave(float x)
+{
+    // 将输入值限制在 [0, 1] 范围内，使用 frac 函数保证值是周期性的
+    x = frac(x);
+
+    // 使用三角函数生成平滑的波形，注意：frac(x) 生成的是 [0, 1] 之间的值
+    return 1.0 - abs(2.0 * x - 1.0);  // 生成平滑的三角波
+}
+
+// SmoothTriangleWave function for a 4-component vector
+inline float4 SmoothTriangleWave(float4 x)
+{
+    return float4(SmoothTriangleWave(x.x), SmoothTriangleWave(x.y), SmoothTriangleWave(x.z), SmoothTriangleWave(x.w));
+}
+
+inline void WindVert_float(float4 pos, float3 normal, float3 vertColor, float4 wind, float speed, float amplitude, out float4 aniPos)
+{	
+    // animParams.x = branch phase
+    // animParams.y = edge flutter factor
+    // animParams.z = primary factor
+    // animParams.w = secondary factor
+
+
+    float bendingFact = 1 - vertColor.b;
+    //wind.xyz = TransformWorldToObject(wind.xyz);
+    //wind.z = wind.z * bendingFact;
+
+    float4 animParams = float4(0, amplitude, bendingFact.xx);
+    float time = _Time.y * float2(speed, 1);
+
+
+    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;
+
+    aniPos = pos;
+	
+}
+
+
+#endif