@tool # Needed so it runs in editor.
extends EditorScenePostImport

# Called right after the scene is imported and gets the root node.
func _post_import(scene):
	# Iterate through the scene and duplicate materials for SurfaceMaterial sub-resources.
	iterate(scene)
	return scene # Remember to return the imported scene

# Recursive function that is called on every node.
func iterate(node):

	if node != null:
		if node is MeshInstance3D:
			var node_internal = node.duplicate()
			var processed_node = process_mesh_instance(node_internal)
			processed_node.set_rotation_degrees(Vector3(90,0,0))
			node.replace_by(processed_node)


		for child in node.get_children():
			iterate(child)

# Function to process a MeshInstance3D node.
func process_mesh_instance(mesh_instance):
	var mesh = mesh_instance.duplicate()

	for i in range(mesh.get_surface_override_material_count()):
		var surface_material = mesh.get_active_material(i)
		if surface_material != null:
			var new_material = surface_material.duplicate()
			new_material.set_render_priority(i)
			new_material.set_texture_filter(0) # nearest neighbor
			new_material.albedo_texture_force_srgb = true
			new_material.set_transparency(2) # Alpha_Scissor
			new_material.set_alpha_scissor_threshold(0.15)
			mesh.mesh.surface_set_material(i, new_material)

	mesh_instance.replace_by(mesh)

	return mesh_instance