Easy way to add and remove bodies on runtime

[andreasfranke1]

Currently, we have issues with adding and removing custom bodies. Adding is a small problem, and by extending from IVBody, the problems have basically disappeared. However, removing still has a major issue: If removing while the camera is focussed, the camera will get removed, too. I'd love to have functions for explicitely adding and removing bodies again, or maybe even have them handle it automatically. We have a workaround for that, which I am just gonna paste here. Maybe it helps.

class_name BodyDeleter

static var instance: BodyDeleter

var _camera: IVCamera
var _selection_manager: IVSelectionManager


static func _static_init() -> void:
	instance = BodyDeleter.new()


func _init() -> void:
	IVGlobal.current_camera_changed.connect(func(camera: IVCamera) -> void: _camera = camera)


func destroy_body(body: IVBody) -> void:
	if not body:
		return
	IVBody.bodies.erase(body.name)
	body.hide()

	await _handle_body_deselect(body)


func _handle_body_deselect(body: IVBody) -> void:
	if not _selection_manager:
		var top_ui: IVTopUI = IVGlobal.program.get(&"TopUI")
		if top_ui:
			_selection_manager = top_ui.selection_manager

	if _selection_manager:
		var selection := _selection_manager.get_selection()
		if selection and body == selection:
			# ...select the parent now.
			_selection_manager.erase_history()
			_selection_manager.select(body.parent)
			# Wait till selection is done.
			while _camera.is_moving or _camera.target == selection:
				await body.get_tree().process_frame

	# Remove world target.
	var world_controller: IVWorldController = IVGlobal.program.get(&"WorldController")
	world_controller.remove_world_target(body)

	# Actually delete bodies.
	if body:
		body.remove()

[charliewhitfield]

I'll bring a robust "removal" system that handles side effects correctly into the next v0.2.3 release.