float worldX = instanceMatrix[3][0];
float worldZ = instanceMatrix[3][2];

float windSpeed = 0.3;
float windScale = 0.04;

vec2 windPos = vec2(worldX, worldZ) * windScale;
vec2 windFlow = windPos + vec2(uTime * windSpeed, uTime * windSpeed * 0.7);

float windStrength = fbm(windFlow);
windStrength = windStrength * 0.6 + 0.3;

float turbulence = fbm(windPos * 3.0 + uTime * 2.0) * 0.15;

vec2 windDir = vec2(
    fbm(windPos * 0.5 + vec2(uTime * 0.1, 0.0)),
    fbm(windPos * 0.5 + vec2(0.0, uTime * 0.1))
);
windDir = normalize(windDir - 0.5) * 0.8;

float swayAmount = (windStrength + turbulence) * uv.y * uv.y;

transformed.x += swayAmount * windDir.x;
transformed.z += swayAmount * windDir.y;
transformed.y -= abs(swayAmount) * 0.2;