Add map background plane to hide transparent window

game/src/Game/GameSession/MapView.gd

@@ -44,6 +44,8 @@ var _map_shader_material : ShaderMaterial
 var _map_mesh_corner : Vector2
 var _map_mesh_dims : Vector2
 
+@export var _map_background_instance : MeshInstance3D
+
 var _mouse_pos_viewport : Vector2 = Vector2(0.5, 0.5)
 var _mouse_pos_map : Vector2 = Vector2(0.5, 0.5)
 var _viewport_dims : Vector2 = Vector2(1, 1)
@@ -56,12 +58,12 @@ var _viewport_dims : Vector2 = Vector2(1, 1)
 # editor, GDExtension, my own extension, or a combination of them.
 # This was an absolute pain to track down. --- hop311
 func _ready() -> void:
-	if _camera == null:
+	if not _camera:
 		push_error("MapView's _camera variable hasn't been set!")
 		return
 	_zoom_target = _camera.position.y
-	if _map_mesh_instance == null:
-		push_error("MapView's _map_mesh variable hasn't been set!")
+	if not _map_mesh_instance:
+		push_error("MapView's _map_mesh_instance variable hasn't been set!")
 		return
 
 	# Shader Material
@@ -91,6 +93,18 @@ func _ready() -> void:
 
 	GameSingleton.province_selected.connect(_on_province_selected)
 
+	if not _map_background_instance:
+		push_error("MapView's _map_background_instance variable hasn't been set!")
+		return
+
+	if not _map_background_instance.mesh is PlaneMesh:
+		push_error("Invalid map background mesh class: ", _map_background_instance.mesh.get_class(), "(expected PlaneMesh)")
+		return
+	var scaled_dims : Vector3 = _map_background_instance.transform.affine_inverse() * Vector3(_map_mesh_dims.x, 0.0, _map_mesh_dims.y)
+	scaled_dims.x *= 1.0 + 2.0 * _map_mesh.get_repeat_proportion()
+	scaled_dims.z *= 2.0
+	(_map_background_instance.mesh as PlaneMesh).set_size(Vector2(scaled_dims.x, scaled_dims.z))
+
 func _notification(what : int) -> void:
 	match what:
 		NOTIFICATION_WM_MOUSE_ENTER: # Mouse inside window

game/src/Game/GameSession/MapView.tscn

@@ -1,4 +1,4 @@
-[gd_scene load_steps=5 format=3 uid="uid://dkehmdnuxih2r"]
+[gd_scene load_steps=7 format=3 uid="uid://dkehmdnuxih2r"]
 
 [ext_resource type="Script" path="res://src/Game/GameSession/MapView.gd" id="1_exccw"]
 [ext_resource type="Shader" path="res://src/Game/GameSession/TerrainMap.gdshader" id="1_upocn"]
@@ -16,11 +16,19 @@ shader_parameter/overlay_tile_factor = null
 
 [sub_resource type="MapMesh" id="MapMesh_3gtsd"]
 
-[node name="MapView" type="Node3D" node_paths=PackedStringArray("_camera", "_map_mesh_instance")]
+[sub_resource type="StandardMaterial3D" id="StandardMaterial3D_irk50"]
+albedo_color = Color(0, 0, 0, 1)
+
+[sub_resource type="PlaneMesh" id="PlaneMesh_fnhgl"]
+material = SubResource("StandardMaterial3D_irk50")
+size = Vector2(6, 2)
+
+[node name="MapView" type="Node3D" node_paths=PackedStringArray("_camera", "_map_mesh_instance", "_map_background_instance")]
 editor_description = "SS-73"
 script = ExtResource("1_exccw")
 _camera = NodePath("MapCamera")
 _map_mesh_instance = NodePath("MapMeshInstance")
+_map_background_instance = NodePath("MapBackgroundInstance")
 
 [node name="MapCamera" type="Camera3D" parent="."]
 transform = Transform3D(1, 0, 0, 0, 0.707107, 0.707107, 0, -0.707107, 0.707107, 0.25, 1.5, -2.75)
@@ -31,3 +39,7 @@ editor_description = "FS-343"
 transform = Transform3D(10, 0, 0, 0, 10, 0, 0, 0, 10, 0, 0, 0)
 material_override = SubResource("ShaderMaterial_tayeg")
 mesh = SubResource("MapMesh_3gtsd")
+
+[node name="MapBackgroundInstance" type="MeshInstance3D" parent="."]
+transform = Transform3D(10, 0, 0, 0, 10, 0, 0, 0, 10, 0, -1, 0)
+mesh = SubResource("PlaneMesh_fnhgl")