Add wind motion to foliage

world/materials/foliage_wind.gdshader

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+shader_type spatial;
+render_mode cull_back, depth_draw_opaque;
+
+uniform vec4 albedo_color : source_color = vec4(1.0);
+uniform float material_roughness = 1.0;
+uniform float material_metallic = 0.0;
+uniform float local_min_y = 0.0;
+uniform float local_height = 1.0;
+uniform float local_wind_strength = 0.08;
+uniform float wind_speed = 0.9;
+uniform float wind_phase = 0.0;
+
+
+void vertex() {
+	float height_ratio = clamp(
+		(VERTEX.y - local_min_y) / max(local_height, 0.001),
+		0.0,
+		1.0
+	);
+	float bend_mask = smoothstep(0.08, 1.0, height_ratio);
+	vec3 world_position = (MODEL_MATRIX * vec4(VERTEX, 1.0)).xyz;
+	float broad_wave = sin(
+		TIME * wind_speed
+		+ dot(world_position.xz, vec2(0.23, 0.17))
+		+ wind_phase
+	);
+	float leaf_flutter = sin(
+		TIME * wind_speed * 2.17
+		+ dot(world_position.xz, vec2(-0.41, 0.37))
+		+ wind_phase * 1.7
+	);
+	float displacement = (
+		broad_wave * 0.72 + leaf_flutter * 0.28
+	) * local_wind_strength * bend_mask;
+	VERTEX.x += displacement;
+	VERTEX.z += displacement * 0.42;
+}
+
+
+void fragment() {
+	ALBEDO = albedo_color.rgb;
+	ROUGHNESS = material_roughness;
+	METALLIC = material_metallic;
+}

world/materials/foliage_wind.gdshader.uid

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+uid://c3q7l8m9n2v4x