Adds static collision to all the instances in a multi mesh node

multimesh_collision.gd

extends MultiMeshInstance

export(Shape) var shape = null

var _shape_rid = null
var _bodies = []

#Done in _enter_tree() and not in _init() because its when the exported shape and world space is set
func _enter_tree():
	_shape_rid = RID(shape)
	
	var i = 0
	while i < multimesh.instance_count:
		var body = PhysicsServer.body_create(PhysicsServer.BODY_MODE_STATIC)
		
		PhysicsServer.body_set_space(body, get_world().space)
		
		PhysicsServer.body_set_collision_layer(body, 1)
		PhysicsServer.body_set_collision_mask(body, 1)
		
		PhysicsServer.body_set_ray_pickable(body, false)
		PhysicsServer.body_add_shape(body, _shape_rid)
		
		_bodies.append(body)
		
		var instance_transform = multimesh.get_instance_transform(i)
		PhysicsServer.body_set_state(body, PhysicsServer.BODY_STATE_TRANSFORM, global_transform * instance_transform)
		
		i +=1

func _notification(what):
	if what == NOTIFICATION_PREDELETE:
		for body in _bodies:
			PhysicsServer.free_rid(body)
		PhysicsServer.free_rid(_shape_rid)