WIP checkpoint: Implement chunk streaming system in GDScript

scripts/dynamic_object_node.gd

@@ -0,0 +1,68 @@
+class_name DynamicObjectNode
+extends Node3D
+## A visual representation of a dynamic (spawnable) world object template.
+##
+## This node is instantiated by [ChunkScene] for each dynamic [WorldObject].
+## Dynamic objects are stored as *templates* in the chunk; their runtime state
+## (position, health, inventory) is managed by the entity system, not by this
+## node. This node renders the template's visual representation so the object
+## is visible in the world.
+##
+## ## Structure
+##
+## ```
+## DynamicObjectNode (Node3D)
+##  └── MeshInstance3D  # the object's visual mesh
+## ```
+
+## The world object data this node represents.
+var world_object: WorldObject = null
+
+## The loaded mesh instance (or placeholder).
+var _mesh_instance: MeshInstance3D = null
+
+
+func _ready() -> void:
+	if world_object == null:
+		return
+	_load_mesh()
+
+
+## Load and attach the object's mesh.
+func _load_mesh() -> void:
+	_mesh_instance = MeshInstance3D.new()
+	_mesh_instance.name = "mesh"
+
+	var mesh := _load_asset_mesh(world_object.asset_id)
+	if mesh == null:
+		mesh = _make_placeholder_mesh()
+
+	_mesh_instance.mesh = mesh
+	add_child(_mesh_instance)
+
+
+## Attempt to load a mesh from the asset path.
+func _load_asset_mesh(asset_id: String) -> Mesh:
+	if asset_id.is_empty():
+		return null
+	var path := "res://assets/%s" % asset_id
+	if ResourceLoader.exists(path):
+		var res := load(path)
+		if res is Mesh:
+			return res
+	return null
+
+
+## Create a simple placeholder sphere mesh when the real asset is unavailable.
+func _make_placeholder_mesh() -> Mesh:
+	var mesh := SphereMesh.new()
+	mesh.radius = 0.5
+	mesh.height = 1.0
+	return mesh
+
+
+## Get the world object's display name.
+func get_display_name() -> String:
+	if world_object == null:
+		return ""
+	return world_object.get_display_name()