fix snow for train and wagons

core/daynight/environment_manager.gd

@@ -39,6 +39,7 @@ var weather_controller: WeatherController
 var day_tween: Tween
 var day_time: float = 0.0
 var pending_environment_nodes: Dictionary = {}
+var weather_shader_no_noise: Material
 
 func _ready() -> void:
 	
@@ -139,7 +140,7 @@ func _apply_dynamic_environment_materials(node: Node) -> void:
 		_apply_wind_noise_to_node(node, NOISE_TEXTURE)
 
 	if node.is_in_group("weather_node"):
-		_apply_weather_overlay_to_node(node, WEATHER_SHADER)
+		_apply_weather_overlay_to_node(node, _get_weather_overlay_material(node))
 
 	if _should_clear_weather_overlay(node):
 		_clear_weather_overlay_from_node(node)
@@ -165,12 +166,24 @@ func _apply_wind_noise_to_node(node: Node, noise_tex: Texture2D) -> void:
 
 func ApplyWeatherShaderToMaterials():
 	for node in get_tree().get_nodes_in_group("weather_node"):
-		_apply_weather_overlay_to_node(node, WEATHER_SHADER)
+		_apply_weather_overlay_to_node(node, _get_weather_overlay_material(node))
 
 	for node in get_tree().get_nodes_in_group("weather_vegetables_node"):
 		if _should_clear_weather_overlay(node):
 			_clear_weather_overlay_from_node(node)
 
+func _get_weather_overlay_material(node: Node) -> Material:
+	if not node.is_in_group("weather_overlay_no_noise"):
+		return WEATHER_SHADER
+
+	if weather_shader_no_noise == null:
+		weather_shader_no_noise = WEATHER_SHADER.duplicate() as Material
+		var shader_material := weather_shader_no_noise as ShaderMaterial
+		if shader_material:
+			shader_material.set_shader_parameter("snow_noise_enabled", false)
+
+	return weather_shader_no_noise
+
 func _apply_weather_overlay_to_node(node: Node, material: Material) -> void:
 	if _should_clear_weather_overlay(node):
 		_clear_weather_overlay_from_node(node)
@@ -218,7 +231,7 @@ func _shader_material_uses_alpha_texture(material: ShaderMaterial) -> bool:
 	return material.shader.code.find("alpha_texture") != -1
 
 func _should_clear_weather_overlay(node: Node) -> bool:
-	return node.is_in_group("weather_vegetables_node")
+	return node.is_in_group("weather_vegetables_node") or node.is_in_group("weather_overlay_ignore")
 
 func select_day_time(normalized_time: float) -> void:
 	#set show_day_time_debug = true to show debug on screen

core/daynight/weather_overlay.gdshader

@@ -17,6 +17,7 @@ global uniform float global_snow_cap_flatness_end  = 0.96;
 global uniform float global_snow_cap_noise_scale   = 0.22;
 global uniform float global_snow_cap_noise_strength = 0.18;
 const float SNOW_VISUAL_RESPONSE = 0.55;
+uniform bool snow_noise_enabled = true;
 uniform float snow_noise_scale : hint_range(0.01, 1.0) = 0.15;
 uniform float snow_edge_softness : hint_range(0.01, 0.5) = 0.2;
 uniform float snow_roughness_variation : hint_range(0.0, 0.3) = 0.15;
@@ -92,6 +93,10 @@ float get_visual_snow_progress(float snow_progress) {
 }
 
 float get_snow_noise_mask(vec3 world_pos, float snow_progress) {
+    if (!snow_noise_enabled) {
+        return 1.0;
+    }
+
     float detail_noise = texture(noise_texture, world_pos.xz * snow_noise_scale).r;
     float broad_noise = texture(noise_texture, world_pos.xz * snow_noise_scale * 0.35 + vec2(19.1, 7.4)).r;
     float combined_noise = mix(detail_noise, broad_noise, 0.35);
@@ -118,7 +123,7 @@ void vertex() {
         world_normal.y
     );
     float accumulation_growth = smoothstep(0.02, 0.45, snow_progress);
-    float cap_noise = fbm(world_pos.xz * global_snow_cap_noise_scale + vec2(11.3, 4.7));
+    float cap_noise = snow_noise_enabled ? fbm(world_pos.xz * global_snow_cap_noise_scale + vec2(11.3, 4.7)) : 0.5;
     float cap_variation = mix(1.0 - global_snow_cap_noise_strength, 1.0 + global_snow_cap_noise_strength, cap_noise);
 
     v_snow_amount = snow_progress;
@@ -133,7 +138,7 @@ void fragment() {
     float facing_up = clamp(world_normal.y, 0.0, 1.0);
     vec3 geometric_normal = normalize(cross(dFdx(world_pos), dFdy(world_pos)));
     float snow_facing_up = max(facing_up, abs(geometric_normal.y));
-    float noise_val = texture(noise_texture, world_pos.xz * snow_noise_scale).r;
+    float noise_val = snow_noise_enabled ? texture(noise_texture, world_pos.xz * snow_noise_scale).r : 0.5;
 
     //Snow
     float snow_progress = v_snow_amount;