show snow on grass

core/biome_generator/rails.gd

@@ -10,6 +10,7 @@ const TRACK_ZERO_SPACING_TARGET_RATIO: float = 0.97
 const TRACK_ZERO_SPACING_MIN_DISTANCE: float = 1.0
 
 enum TrainStartMode { RANDOM_POSITION, SPECIFIED_STATION, SPECIFIED_POSITION }
+enum TrainFacingDirection { KEEP_PATH_DIRECTION, LOCOMOTIVE_LEFT, LOCOMOTIVE_RIGHT }
 
 @export_group("Train")
 ##train speed
@@ -46,6 +47,7 @@ enum TrainStartMode { RANDOM_POSITION, SPECIFIED_STATION, SPECIFIED_POSITION }
 @export var train_start_delay_seconds: float = 0.0
 @export var train_start_after_delay: bool = true
 @export var train_start_acceleration_seconds: float = 4.0
+@export_enum("keep_path_direction", "locomotive_left", "locomotive_right") var train_facing_direction: int = TrainFacingDirection.KEEP_PATH_DIRECTION
 
 @export_group("Rails Bulding")
 ##distance between sleepers of the rails
@@ -103,6 +105,7 @@ var wagon_instances: Array[Node3D] = []
 var wagon_progress_offsets: Array[float] = []
 var _initial_is_inmotion: bool = true
 var _is_photo_mode_active: bool = false
+var _train_direction_sign: float = 1.0
 
 func _ready() -> void:
 	randomize()
@@ -144,8 +147,32 @@ func _apply_initial_train_start() -> void:
 			train_progress = wrapf(train_start_position, 0.0, total_length)
 			_update_next_stop_index_from_progress()
 
+	_apply_train_facing_direction(total_length)
+	_update_next_stop_index_from_progress()
 	_snap_train_to_progress()
 
+func _apply_train_facing_direction(total_length: float) -> void:
+	_train_direction_sign = 1.0
+	if train_facing_direction == TrainFacingDirection.KEEP_PATH_DIRECTION or curve == null:
+		return
+	if total_length <= 0.0:
+		return
+
+	var center_progress: float = wrapf(train_progress, 0.0, total_length)
+	var center_position: Vector3 = to_global(curve.sample_baked(center_progress, true))
+	var forward_progress: float = wrapf(center_progress + 2.0, 0.0, total_length)
+	var forward_position: Vector3 = to_global(curve.sample_baked(forward_progress, true))
+	var forward_direction: Vector3 = forward_position - center_position
+	if forward_direction.length_squared() <= 0.0001 or is_zero_approx(forward_direction.x):
+		return
+
+	var desired_x_sign: float = -1.0 if train_facing_direction == TrainFacingDirection.LOCOMOTIVE_LEFT else 1.0
+	if forward_direction.x * desired_x_sign < 0.0:
+		_train_direction_sign = -1.0
+
+	if not is_zero_approx(train_speed):
+		train_speed = absf(train_speed) * _train_direction_sign
+
 func _apply_train_start_delay() -> void:
 	if not _initial_is_inmotion:
 		return
@@ -207,13 +234,9 @@ func _snap_train_to_progress() -> void:
 
 	train_progress = wrapf(train_progress, 0.0, total_length)
 	var center_position: Vector3 = to_global(curve.sample_baked(train_progress, true))
-	var prog_forward: float = wrapf(train_progress + 2.0, 0.0, total_length)
-	var forward_position: Vector3 = to_global(curve.sample_baked(prog_forward, true))
 
 	train_instance.global_position = center_position
-	if center_position.distance_to(forward_position) > 0.01:
+	_orient_vehicle_to_track(train_instance, train_progress, total_length)
-		train_instance.look_at(forward_position, Vector3.UP)
-		train_instance.rotate_y(PI)
 
 	if cameras:
 		cameras.global_position = center_position
@@ -452,8 +475,7 @@ func train_move(delta: float) -> void:
 
 		if center_position.distance_to(forward_position) > 0.01:
 			train_instance.global_position = center_position
-			train_instance.look_at(forward_position, Vector3.UP)
+			_orient_vehicle_to_track(train_instance, train_progress, total_length)
-			train_instance.rotate_y(PI) 
 			
 		if cameras:
 			cameras.global_position = center_position
@@ -658,7 +680,7 @@ func _snap_wagons_to_progress(total_length: float = 0.0) -> void:
 		if i < wagon_progress_offsets.size():
 			wagon_offset = wagon_progress_offsets[i]
 
-		var wagon_progress: float = train_progress - wagon_offset
+		var wagon_progress: float = train_progress - wagon_offset * _train_direction_sign
 		var segment_spacing: float = maxf(wagon_offset - previous_wagon_offset, 0.1)
 
 		var vehicle_progress: float = wrapf(wagon_progress, 0.0, total_length)
@@ -670,18 +692,27 @@ func _snap_wagons_to_progress(total_length: float = 0.0) -> void:
 			vehicle_progress = _lerp_progress_on_track(vehicle_progress, corrected_progress, zero_spacing_fix_weight, total_length)
 			center_position = to_global(curve.sample_baked(vehicle_progress, true))
 
-		var prog_forward: float = wrapf(vehicle_progress + 2.0, 0.0, total_length)
-		var forward_position: Vector3 = to_global(curve.sample_baked(prog_forward, true))
-
 		wagon.global_position = center_position
-		if center_position.distance_to(forward_position) > 0.01:
+		_orient_vehicle_to_track(wagon, vehicle_progress, total_length)
-			wagon.look_at(forward_position, Vector3.UP)
-			wagon.rotate_y(PI)
 
 		previous_progress = vehicle_progress
 		previous_position = center_position
 		previous_wagon_offset = wagon_offset
 
+func _orient_vehicle_to_track(vehicle: Node3D, progress: float, total_length: float) -> void:
+	if vehicle == null or curve == null or total_length <= 0.0:
+		return
+
+	var center_progress: float = wrapf(progress, 0.0, total_length)
+	var center_position: Vector3 = to_global(curve.sample_baked(center_progress, true))
+	var forward_progress: float = wrapf(center_progress + 2.0 * _train_direction_sign, 0.0, total_length)
+	var forward_position: Vector3 = to_global(curve.sample_baked(forward_progress, true))
+	if center_position.distance_to(forward_position) <= 0.01:
+		return
+
+	vehicle.look_at(forward_position, Vector3.UP)
+	vehicle.rotate_y(PI)
+
 func _get_zero_spacing_fix_weight(previous_progress: float, vehicle_progress: float, total_length: float) -> float:
 	var distance_to_zero: float = minf(
 		_get_progress_distance_to_zero(previous_progress, total_length),
@@ -699,13 +730,13 @@ func _get_zero_spacing_target_distance(segment_spacing: float) -> float:
 
 func _find_zero_spacing_progress(previous_progress: float, previous_position: Vector3, segment_spacing: float, minimum_distance: float, total_length: float) -> float:
 	var start_distance: float = minf(minimum_distance, segment_spacing)
-	var best_progress: float = wrapf(previous_progress - start_distance, 0.0, total_length)
+	var best_progress: float = wrapf(previous_progress - start_distance * _train_direction_sign, 0.0, total_length)
 	var search_limit: float = minf(maxf(segment_spacing, minimum_distance) + TRACK_ZERO_SPACING_SEARCH_EXTRA, total_length)
 	var search_distance: float = start_distance
 	var previous_search_distance: float = start_distance
 
 	while search_distance <= search_limit:
-		var candidate_progress: float = wrapf(previous_progress - search_distance, 0.0, total_length)
+		var candidate_progress: float = wrapf(previous_progress - search_distance * _train_direction_sign, 0.0, total_length)
 		var candidate_position: Vector3 = to_global(curve.sample_baked(candidate_progress, true))
 		best_progress = candidate_progress
 		if previous_position.distance_to(candidate_position) >= minimum_distance:

core/daynight/grass_leaves.gdshader

@@ -15,6 +15,8 @@ global uniform float global_snow_melt_speed = 0.1;
 global uniform float global_snow_amount = 0.0;
 global uniform vec4 global_snow_color = vec4(0.92, 0.96, 1.0, 1.0);
 global uniform float global_rain_intensity;
+const float GRASS_FULL_SNOW_START = 0.58;
+const float GRASS_FULL_SNOW_END = 0.86;
 
 // --- PARAMETRI ESTETICI ---
 uniform bool billboard_enabled = true; 
@@ -141,7 +143,7 @@ void fragment() {
 	float snow_mask = smoothstep(snow_start, 1.0, top_mask) * snow_amount * snow_visibility;
 	snow_mask *= step(0.01, snow_amount);
 	snow_mask = clamp(snow_mask, 0.0, 1.0);
-	float full_snow_mask = smoothstep(0.72, 1.0, snow_amount) * step(0.01, snow_visibility);
+	float full_snow_mask = smoothstep(GRASS_FULL_SNOW_START, GRASS_FULL_SNOW_END, snow_amount) * step(0.01, snow_visibility);
 	float final_snow_mask = max(snow_mask, full_snow_mask);
 	
 	vec3 snow_base_color = max(snow_color.rgb, global_snow_color.rgb);

core/daynight/tree_leaves.gdshader

@@ -13,6 +13,8 @@ global uniform float global_snow_melt_speed = 0.1;
 global uniform float global_snow_amount = 0.0;
 global uniform vec4  global_snow_color;
 global uniform float global_rain_intensity;
+const float LEAVES_FULL_SNOW_START = 0.58;
+const float LEAVES_FULL_SNOW_END = 0.86;
 
 uniform sampler2D wind_noise : filter_linear_mipmap;
 uniform bool billboard_enabled = true;
@@ -110,7 +112,7 @@ void fragment() {
     float top_mask = 1.0 - shifted_uv.y;
     float snow_mask = smoothstep(1.0 - snow_amount * 1.35, 1.08 - snow_amount * 1.35, top_mask) * snow_visibility;
     snow_mask *= step(0.01, snow_amount);
-    float full_snow_mask = smoothstep(0.78, 1.0, snow_amount) * clamp(snow_visibility, 0.0, 1.0);
+    float full_snow_mask = smoothstep(LEAVES_FULL_SNOW_START, LEAVES_FULL_SNOW_END, snow_amount) * clamp(snow_visibility, 0.0, 1.0);
     float final_snow_mask = max(snow_mask, full_snow_mask);
 
     float snow_light = mix(0.82, 1.0, max(v_shade_factor, 0.35));

core/daynight/weather_overlay.gdshader

@@ -17,6 +17,8 @@ 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;
+const float FULL_SNOW_VISUAL_START = 0.82;
+const float FULL_SNOW_VISUAL_END = 0.98;
 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;
@@ -156,6 +158,8 @@ void fragment() {
     float snow_factor = max(snow_edge * snow_coverage, flat_accumulation);
     float snow_opacity = clamp(snow_factor, 0.0, 1.0);
     snow_opacity = max(snow_opacity, flat_accumulation * mix(0.45, 0.9, snow_noise_mask));
+    float full_snow_opacity = snow_edge * smoothstep(FULL_SNOW_VISUAL_START, FULL_SNOW_VISUAL_END, snow_progress);
+    snow_opacity = max(snow_opacity, full_snow_opacity);
 
     float shade = mix(-snow_color_variation, snow_color_variation, noise_val);
     vec3 snow_albedo = clamp(global_snow_color.rgb + vec3(shade), 0.0, 1.0);

tgcc/main menu/main_menu_test.tscn

@@ -324,6 +324,7 @@ train_start_mode = 2
 train_start_stop_index = 0
 train_start_position = 540.0
 train_start_after_delay = false
+train_facing_direction = 2
 sleepers_model = ExtResource("10_00nq7")
 fireworks_scene = ExtResource("11_aylkj")