ObjectID converted to a structure, fixes many bugs where used incorrectly as 32 bits.

25 files changed, 72 insertions, 81 deletions

diff --git a/scene/2d/area_2d.cpp b/scene/2d/area_2d.cpp
index 8302ba5336..b661db2e52 100644
--- a/scene/2d/area_2d.cpp
+++ b/scene/2d/area_2d.cpp
@@ -148,7 +148,7 @@ void Area2D::_body_exit_tree(ObjectID p_id) {
 	}
 }
 
-void Area2D::_body_inout(int p_status, const RID &p_body, int p_instance, int p_body_shape, int p_area_shape) {
+void Area2D::_body_inout(int p_status, const RID &p_body, ObjectID p_instance, int p_body_shape, int p_area_shape) {
 
 	bool body_in = p_status == Physics2DServer::AREA_BODY_ADDED;
 	ObjectID objid = p_instance;
@@ -251,7 +251,7 @@ void Area2D::_area_exit_tree(ObjectID p_id) {
 	}
 }
 
-void Area2D::_area_inout(int p_status, const RID &p_area, int p_instance, int p_area_shape, int p_self_shape) {
+void Area2D::_area_inout(int p_status, const RID &p_area, ObjectID p_instance, int p_area_shape, int p_self_shape) {
 
 	bool area_in = p_status == Physics2DServer::AREA_BODY_ADDED;
 	ObjectID objid = p_instance;
diff --git a/scene/2d/area_2d.h b/scene/2d/area_2d.h
index 6d9386c535..c5e6635412 100644
--- a/scene/2d/area_2d.h
+++ b/scene/2d/area_2d.h
@@ -62,7 +62,7 @@ private:
 	bool monitorable;
 	bool locked;
 
-	void _body_inout(int p_status, const RID &p_body, int p_instance, int p_body_shape, int p_area_shape);
+	void _body_inout(int p_status, const RID &p_body, ObjectID p_instance, int p_body_shape, int p_area_shape);
 
 	void _body_enter_tree(ObjectID p_id);
 	void _body_exit_tree(ObjectID p_id);
@@ -94,7 +94,7 @@ private:
 
 	Map<ObjectID, BodyState> body_map;
 
-	void _area_inout(int p_status, const RID &p_area, int p_instance, int p_area_shape, int p_self_shape);
+	void _area_inout(int p_status, const RID &p_area, ObjectID p_instance, int p_area_shape, int p_self_shape);
 
 	void _area_enter_tree(ObjectID p_id);
 	void _area_exit_tree(ObjectID p_id);
diff --git a/scene/2d/camera_2d.cpp b/scene/2d/camera_2d.cpp
index e9f8c5dff2..7ec770597e 100644
--- a/scene/2d/camera_2d.cpp
+++ b/scene/2d/camera_2d.cpp
@@ -608,7 +608,7 @@ void Camera2D::set_custom_viewport(Node *p_viewport) {
 	if (custom_viewport) {
 		custom_viewport_id = custom_viewport->get_instance_id();
 	} else {
-		custom_viewport_id = 0;
+		custom_viewport_id = ObjectID();
 	}
 
 	if (is_inside_tree()) {
@@ -795,7 +795,7 @@ Camera2D::Camera2D() {
 	smoothing_enabled = false;
 	limit_smoothing_enabled = false;
 	custom_viewport = NULL;
-	custom_viewport_id = 0;
+
 	process_mode = CAMERA2D_PROCESS_IDLE;
 
 	smoothing = 5.0;
diff --git a/scene/2d/canvas_item.cpp b/scene/2d/canvas_item.cpp
index eff58a4fb3..aca0c4c959 100644
--- a/scene/2d/canvas_item.cpp
+++ b/scene/2d/canvas_item.cpp
@@ -997,7 +997,7 @@ ObjectID CanvasItem::get_canvas_layer_instance_id() const {
 	if (canvas_layer) {
 		return canvas_layer->get_instance_id();
 	} else {
-		return 0;
+		return ObjectID();
 	}
 }
 
diff --git a/scene/2d/collision_object_2d.cpp b/scene/2d/collision_object_2d.cpp
index 3e9e63a7f0..4af2e846f7 100644
--- a/scene/2d/collision_object_2d.cpp
+++ b/scene/2d/collision_object_2d.cpp
@@ -95,9 +95,9 @@ void CollisionObject2D::_notification(int p_what) {
 		case NOTIFICATION_EXIT_CANVAS: {
 
 			if (area)
-				Physics2DServer::get_singleton()->area_attach_canvas_instance_id(rid, 0);
+				Physics2DServer::get_singleton()->area_attach_canvas_instance_id(rid, ObjectID());
 			else
-				Physics2DServer::get_singleton()->body_attach_canvas_instance_id(rid, 0);
+				Physics2DServer::get_singleton()->body_attach_canvas_instance_id(rid, ObjectID());
 		} break;
 	}
 }
diff --git a/scene/2d/physics_body_2d.cpp b/scene/2d/physics_body_2d.cpp
index d42bd6adaf..d1fe5caf7e 100644
--- a/scene/2d/physics_body_2d.cpp
+++ b/scene/2d/physics_body_2d.cpp
@@ -1544,7 +1544,7 @@ Object *KinematicCollision2D::get_local_shape() const {
 
 Object *KinematicCollision2D::get_collider() const {
 
-	if (collision.collider) {
+	if (collision.collider.is_valid()) {
 		return ObjectDB::get_instance(collision.collider);
 	}
 
@@ -1608,7 +1608,7 @@ void KinematicCollision2D::_bind_methods() {
 }
 
 KinematicCollision2D::KinematicCollision2D() {
-	collision.collider = 0;
+
 	collision.collider_shape = 0;
 	collision.local_shape = 0;
 	owner = NULL;
diff --git a/scene/2d/polygon_2d.cpp b/scene/2d/polygon_2d.cpp
index dc953b2d7d..ba5b7d29e7 100644
--- a/scene/2d/polygon_2d.cpp
+++ b/scene/2d/polygon_2d.cpp
@@ -108,7 +108,7 @@ void Polygon2D::_notification(int p_what) {
 				skeleton_node = Object::cast_to<Skeleton2D>(get_node(skeleton));
 			}
 
-			ObjectID new_skeleton_id = 0;
+			ObjectID new_skeleton_id;
 
 			if (skeleton_node) {
 				VS::get_singleton()->canvas_item_attach_skeleton(get_canvas_item(), skeleton_node->get_skeleton());
@@ -734,7 +734,7 @@ Polygon2D::Polygon2D() {
 	color = Color(1, 1, 1);
 	rect_cache_dirty = true;
 	internal_vertices = 0;
-	current_skeleton_id = 0;
+
 	specular_color = Color(1, 1, 1, 1);
 	shininess = 1.0;
 }
diff --git a/scene/2d/ray_cast_2d.cpp b/scene/2d/ray_cast_2d.cpp
index 3252e02e38..fd6e0aebcc 100644
--- a/scene/2d/ray_cast_2d.cpp
+++ b/scene/2d/ray_cast_2d.cpp
@@ -78,7 +78,7 @@ bool RayCast2D::is_colliding() const {
 }
 Object *RayCast2D::get_collider() const {
 
-	if (against == 0)
+	if (against.is_null())
 		return NULL;
 
 	return ObjectDB::get_instance(against);
@@ -225,7 +225,7 @@ void RayCast2D::_update_raycast_state() {
 		against_shape = rr.shape;
 	} else {
 		collided = false;
-		against = 0;
+		against = ObjectID();
 		against_shape = 0;
 	}
 }
@@ -339,7 +339,7 @@ void RayCast2D::_bind_methods() {
 RayCast2D::RayCast2D() {
 
 	enabled = false;
-	against = 0;
+
 	collided = false;
 	against_shape = 0;
 	collision_mask = 1;
diff --git a/scene/2d/remote_transform_2d.cpp b/scene/2d/remote_transform_2d.cpp
index 53072f942d..ec50f5f922 100644
--- a/scene/2d/remote_transform_2d.cpp
+++ b/scene/2d/remote_transform_2d.cpp
@@ -33,7 +33,7 @@
 
 void RemoteTransform2D::_update_cache() {
 
-	cache = 0;
+	cache = ObjectID();
 	if (has_node(remote_node)) {
 		Node *node = get_node(remote_node);
 		if (!node || this == node || node->is_a_parent_of(this) || this->is_a_parent_of(node)) {
@@ -49,7 +49,7 @@ void RemoteTransform2D::_update_remote() {
 	if (!is_inside_tree())
 		return;
 
-	if (!cache)
+	if (cache.is_null())
 		return;
 
 	Node2D *n = Object::cast_to<Node2D>(ObjectDB::get_instance(cache));
@@ -119,7 +119,7 @@ void RemoteTransform2D::_notification(int p_what) {
 			if (!is_inside_tree())
 				break;
 
-			if (cache) {
+			if (cache.is_valid()) {
 
 				_update_remote();
 			}
@@ -225,6 +225,5 @@ RemoteTransform2D::RemoteTransform2D() {
 	update_remote_rotation = true;
 	update_remote_scale = true;
 
-	cache = 0;
 	set_notify_transform(true);
 }
diff --git a/scene/3d/area.cpp b/scene/3d/area.cpp
index 67f57a1aa3..62908e2b0f 100644
--- a/scene/3d/area.cpp
+++ b/scene/3d/area.cpp
@@ -147,7 +147,7 @@ void Area::_body_exit_tree(ObjectID p_id) {
 	}
 }
 
-void Area::_body_inout(int p_status, const RID &p_body, int p_instance, int p_body_shape, int p_area_shape) {
+void Area::_body_inout(int p_status, const RID &p_body, ObjectID p_instance, int p_body_shape, int p_area_shape) {
 
 	bool body_in = p_status == PhysicsServer::AREA_BODY_ADDED;
 	ObjectID objid = p_instance;
@@ -340,7 +340,7 @@ void Area::_area_exit_tree(ObjectID p_id) {
 	}
 }
 
-void Area::_area_inout(int p_status, const RID &p_area, int p_instance, int p_area_shape, int p_self_shape) {
+void Area::_area_inout(int p_status, const RID &p_area, ObjectID p_instance, int p_area_shape, int p_self_shape) {
 
 	bool area_in = p_status == PhysicsServer::AREA_BODY_ADDED;
 	ObjectID objid = p_instance;
diff --git a/scene/3d/area.h b/scene/3d/area.h
index ca66f41f60..7fe61430fa 100644
--- a/scene/3d/area.h
+++ b/scene/3d/area.h
@@ -62,7 +62,7 @@ private:
 	bool monitorable;
 	bool locked;
 
-	void _body_inout(int p_status, const RID &p_body, int p_instance, int p_body_shape, int p_area_shape);
+	void _body_inout(int p_status, const RID &p_body, ObjectID p_instance, int p_body_shape, int p_area_shape);
 
 	void _body_enter_tree(ObjectID p_id);
 	void _body_exit_tree(ObjectID p_id);
@@ -94,7 +94,7 @@ private:
 
 	Map<ObjectID, BodyState> body_map;
 
-	void _area_inout(int p_status, const RID &p_area, int p_instance, int p_area_shape, int p_self_shape);
+	void _area_inout(int p_status, const RID &p_area, ObjectID p_instance, int p_area_shape, int p_self_shape);
 
 	void _area_enter_tree(ObjectID p_id);
 	void _area_exit_tree(ObjectID p_id);
diff --git a/scene/3d/physics_body.cpp b/scene/3d/physics_body.cpp
index fbfd372272..5d5cb4dfce 100644
--- a/scene/3d/physics_body.cpp
+++ b/scene/3d/physics_body.cpp
@@ -1493,7 +1493,7 @@ Object *KinematicCollision::get_local_shape() const {
 
 Object *KinematicCollision::get_collider() const {
 
-	if (collision.collider) {
+	if (collision.collider.is_valid()) {
 		return ObjectDB::get_instance(collision.collider);
 	}
 
@@ -1557,7 +1557,7 @@ void KinematicCollision::_bind_methods() {
 }
 
 KinematicCollision::KinematicCollision() {
-	collision.collider = 0;
+
 	collision.collider_shape = 0;
 	collision.local_shape = 0;
 	owner = NULL;
diff --git a/scene/3d/ray_cast.cpp b/scene/3d/ray_cast.cpp
index 0c976b9fb1..be1426f13c 100644
--- a/scene/3d/ray_cast.cpp
+++ b/scene/3d/ray_cast.cpp
@@ -80,7 +80,7 @@ bool RayCast::is_colliding() const {
 }
 Object *RayCast::get_collider() const {
 
-	if (against == 0)
+	if (against.is_null())
 		return NULL;
 
 	return ObjectDB::get_instance(against);
@@ -219,7 +219,7 @@ void RayCast::_update_raycast_state() {
 		against_shape = rr.shape;
 	} else {
 		collided = false;
-		against = 0;
+		against = ObjectID();
 		against_shape = 0;
 	}
 }
@@ -393,7 +393,7 @@ void RayCast::_clear_debug_shape() {
 RayCast::RayCast() {
 
 	enabled = false;
-	against = 0;
+
 	collided = false;
 	against_shape = 0;
 	collision_mask = 1;
diff --git a/scene/3d/remote_transform.cpp b/scene/3d/remote_transform.cpp
index 983af7a9ec..9ef43647ba 100644
--- a/scene/3d/remote_transform.cpp
+++ b/scene/3d/remote_transform.cpp
@@ -31,7 +31,7 @@
 #include "remote_transform.h"
 
 void RemoteTransform::_update_cache() {
-	cache = 0;
+	cache = ObjectID();
 	if (has_node(remote_node)) {
 		Node *node = get_node(remote_node);
 		if (!node || this == node || node->is_a_parent_of(this) || this->is_a_parent_of(node)) {
@@ -47,7 +47,7 @@ void RemoteTransform::_update_remote() {
 	if (!is_inside_tree())
 		return;
 
-	if (!cache)
+	if (cache.is_null())
 		return;
 
 	Spatial *n = Object::cast_to<Spatial>(ObjectDB::get_instance(cache));
@@ -114,7 +114,7 @@ void RemoteTransform::_notification(int p_what) {
 			if (!is_inside_tree())
 				break;
 
-			if (cache) {
+			if (cache.is_valid()) {
 
 				_update_remote();
 			}
@@ -219,6 +219,5 @@ RemoteTransform::RemoteTransform() {
 	update_remote_rotation = true;
 	update_remote_scale = true;
 
-	cache = 0;
 	set_notify_transform(true);
 }
diff --git a/scene/3d/skeleton.cpp b/scene/3d/skeleton.cpp
index 3e4cd54664..aa5c439f8a 100644
--- a/scene/3d/skeleton.cpp
+++ b/scene/3d/skeleton.cpp
@@ -138,7 +138,7 @@ bool Skeleton::_get(const StringName &p_path, Variant &r_ret) const {
 	else if (what == "bound_children") {
 		Array children;
 
-		for (const List<uint32_t>::Element *E = bones[which].nodes_bound.front(); E; E = E->next()) {
+		for (const List<ObjectID>::Element *E = bones[which].nodes_bound.front(); E; E = E->next()) {
 
 			Object *obj = ObjectDB::get_instance(E->get());
 			ERR_CONTINUE(!obj);
@@ -302,7 +302,7 @@ void Skeleton::_notification(int p_what) {
 					b.global_pose_override_amount = 0.0;
 				}
 
-				for (List<uint32_t>::Element *E = b.nodes_bound.front(); E; E = E->next()) {
+				for (List<ObjectID>::Element *E = b.nodes_bound.front(); E; E = E->next()) {
 
 					Object *obj = ObjectDB::get_instance(E->get());
 					ERR_CONTINUE(!obj);
@@ -505,9 +505,9 @@ void Skeleton::bind_child_node_to_bone(int p_bone, Node *p_node) {
 	ERR_FAIL_NULL(p_node);
 	ERR_FAIL_INDEX(p_bone, bones.size());
 
-	uint32_t id = p_node->get_instance_id();
+	ObjectID id = p_node->get_instance_id();
 
-	for (const List<uint32_t>::Element *E = bones[p_bone].nodes_bound.front(); E; E = E->next()) {
+	for (const List<ObjectID>::Element *E = bones[p_bone].nodes_bound.front(); E; E = E->next()) {
 
 		if (E->get() == id)
 			return; // already here
@@ -520,14 +520,14 @@ void Skeleton::unbind_child_node_from_bone(int p_bone, Node *p_node) {
 	ERR_FAIL_NULL(p_node);
 	ERR_FAIL_INDEX(p_bone, bones.size());
 
-	uint32_t id = p_node->get_instance_id();
+	ObjectID id = p_node->get_instance_id();
 	bones.write[p_bone].nodes_bound.erase(id);
 }
 void Skeleton::get_bound_child_nodes_to_bone(int p_bone, List<Node *> *p_bound) const {
 
 	ERR_FAIL_INDEX(p_bone, bones.size());
 
-	for (const List<uint32_t>::Element *E = bones[p_bone].nodes_bound.front(); E; E = E->next()) {
+	for (const List<ObjectID>::Element *E = bones[p_bone].nodes_bound.front(); E; E = E->next()) {
 
 		Object *obj = ObjectDB::get_instance(E->get());
 		ERR_CONTINUE(!obj);
diff --git a/scene/3d/skeleton.h b/scene/3d/skeleton.h
index 9599510850..b42c2112e3 100644
--- a/scene/3d/skeleton.h
+++ b/scene/3d/skeleton.h
@@ -99,7 +99,7 @@ private:
 		PhysicalBone *cache_parent_physical_bone;
 #endif // _3D_DISABLED
 
-		List<uint32_t> nodes_bound;
+		List<ObjectID> nodes_bound;
 
 		Bone() {
 			parent = -1;
diff --git a/scene/animation/animation_player.cpp b/scene/animation/animation_player.cpp
index 7ec7037dd7..740dad9a1a 100644
--- a/scene/animation/animation_player.cpp
+++ b/scene/animation/animation_player.cpp
@@ -249,7 +249,7 @@ void AnimationPlayer::_ensure_node_caches(AnimationData *p_anim) {
 		Vector<StringName> leftover_path;
 		Node *child = parent->get_node_and_resource(a->track_get_path(i), resource, leftover_path);
 		ERR_CONTINUE_MSG(!child, "On Animation: '" + p_anim->name + "', couldn't resolve track:  '" + String(a->track_get_path(i)) + "'."); // couldn't find the child node
-		uint32_t id = resource.is_valid() ? resource->get_instance_id() : child->get_instance_id();
+		ObjectID id = resource.is_valid() ? resource->get_instance_id() : child->get_instance_id();
 		int bone_idx = -1;
 
 		if (a->track_get_path(i).get_subname_count() == 1 && Object::cast_to<Skeleton>(child)) {
diff --git a/scene/animation/animation_player.h b/scene/animation/animation_player.h
index 06f762e63e..48829b02b9 100644
--- a/scene/animation/animation_player.h
+++ b/scene/animation/animation_player.h
@@ -159,17 +159,15 @@ private:
 
 	struct TrackNodeCacheKey {
 
-		uint32_t id;
+		ObjectID id;
 		int bone_idx;
 
 		inline bool operator<(const TrackNodeCacheKey &p_right) const {
 
-			if (id < p_right.id)
-				return true;
-			else if (id > p_right.id)
-				return false;
-			else
+			if (id == p_right.id)
 				return bone_idx < p_right.bone_idx;
+			else
+				return id < p_right.id;
 		}
 	};
 
diff --git a/scene/animation/animation_tree.cpp b/scene/animation/animation_tree.cpp
index c28f8dc824..a08cc0927b 100644
--- a/scene/animation/animation_tree.cpp
+++ b/scene/animation/animation_tree.cpp
@@ -767,7 +767,7 @@ void AnimationTree::_process_graph(float p_delta) {
 
 	AnimationPlayer *player = Object::cast_to<AnimationPlayer>(get_node(animation_player));
 
-	ObjectID current_animation_player = 0;
+	ObjectID current_animation_player;
 
 	if (player) {
 		current_animation_player = player->get_instance_id();
@@ -775,7 +775,7 @@ void AnimationTree::_process_graph(float p_delta) {
 
 	if (last_animation_player != current_animation_player) {
 
-		if (last_animation_player) {
+		if (last_animation_player.is_valid()) {
 			Object *old_player = ObjectDB::get_instance(last_animation_player);
 			if (old_player) {
 				old_player->disconnect("caches_cleared", this, "_clear_caches");
@@ -1296,7 +1296,7 @@ void AnimationTree::_notification(int p_what) {
 
 	if (p_what == NOTIFICATION_EXIT_TREE) {
 		_clear_caches();
-		if (last_animation_player) {
+		if (last_animation_player.is_valid()) {
 
 			Object *player = ObjectDB::get_instance(last_animation_player);
 			if (player) {
@@ -1304,7 +1304,7 @@ void AnimationTree::_notification(int p_what) {
 			}
 		}
 	} else if (p_what == NOTIFICATION_ENTER_TREE) {
-		if (last_animation_player) {
+		if (last_animation_player.is_valid()) {
 
 			Object *player = ObjectDB::get_instance(last_animation_player);
 			if (player) {
@@ -1584,7 +1584,6 @@ AnimationTree::AnimationTree() {
 	process_pass = 1;
 	started = true;
 	properties_dirty = true;
-	last_animation_player = 0;
 }
 
 AnimationTree::~AnimationTree() {
diff --git a/scene/animation/animation_tree.h b/scene/animation/animation_tree.h
index 0a8dc8109f..8769e2c61d 100644
--- a/scene/animation/animation_tree.h
+++ b/scene/animation/animation_tree.h
@@ -187,7 +187,6 @@ private:
 			setup_pass = 0;
 			process_pass = 0;
 			object = NULL;
-			object_id = 0;
 		}
 		virtual ~TrackCache() {}
 	};
diff --git a/scene/gui/control.cpp b/scene/gui/control.cpp
index be211504a6..b7bc2f9c9e 100644
--- a/scene/gui/control.cpp
+++ b/scene/gui/control.cpp
@@ -705,12 +705,12 @@ void Control::set_drag_forwarding(Control *p_target) {
 	if (p_target)
 		data.drag_owner = p_target->get_instance_id();
 	else
-		data.drag_owner = 0;
+		data.drag_owner = ObjectID();
 }
 
 Variant Control::get_drag_data(const Point2 &p_point) {
 
-	if (data.drag_owner) {
+	if (data.drag_owner.is_valid()) {
 		Object *obj = ObjectDB::get_instance(data.drag_owner);
 		if (obj) {
 			Control *c = Object::cast_to<Control>(obj);
@@ -732,7 +732,7 @@ Variant Control::get_drag_data(const Point2 &p_point) {
 
 bool Control::can_drop_data(const Point2 &p_point, const Variant &p_data) const {
 
-	if (data.drag_owner) {
+	if (data.drag_owner.is_valid()) {
 		Object *obj = ObjectDB::get_instance(data.drag_owner);
 		if (obj) {
 			Control *c = Object::cast_to<Control>(obj);
@@ -753,7 +753,7 @@ bool Control::can_drop_data(const Point2 &p_point, const Variant &p_data) const
 }
 void Control::drop_data(const Point2 &p_point, const Variant &p_data) {
 
-	if (data.drag_owner) {
+	if (data.drag_owner.is_valid()) {
 		Object *obj = ObjectDB::get_instance(data.drag_owner);
 		if (obj) {
 			Control *c = Object::cast_to<Control>(obj);
@@ -2224,7 +2224,7 @@ void Control::_modal_stack_remove() {
 
 	get_viewport()->_gui_remove_from_modal_stack(element, data.modal_prev_focus_owner);
 
-	data.modal_prev_focus_owner = 0;
+	data.modal_prev_focus_owner = ObjectID();
 }
 
 void Control::_propagate_theme_changed(CanvasItem *p_at, Control *p_owner, bool p_assign) {
@@ -3110,7 +3110,7 @@ Control::Control() {
 	data.rotation = 0;
 	data.parent_canvas_item = NULL;
 	data.scale = Vector2(1, 1);
-	data.drag_owner = 0;
+
 	data.modal_frame = 0;
 	data.block_minimum_size_adjust = false;
 	data.disable_visibility_clip = false;
@@ -3125,7 +3125,6 @@ Control::Control() {
 		data.margin[i] = 0;
 	}
 	data.focus_mode = FOCUS_NONE;
-	data.modal_prev_focus_owner = 0;
 }
 
 Control::~Control() {
diff --git a/scene/gui/tree.cpp b/scene/gui/tree.cpp
index 7bfe060065..08835be9fd 100644
--- a/scene/gui/tree.cpp
+++ b/scene/gui/tree.cpp
@@ -1399,7 +1399,7 @@ int Tree::draw_item(const Point2i &p_pos, const Point2 &p_draw_ofs, const Size2
 				} break;
 				case TreeItem::CELL_MODE_CUSTOM: {
 
-					if (p_item->cells[i].custom_draw_obj) {
+					if (p_item->cells[i].custom_draw_obj.is_valid()) {
 
 						Object *cdo = ObjectDB::get_instance(p_item->cells[i].custom_draw_obj);
 						if (cdo)
diff --git a/scene/gui/tree.h b/scene/gui/tree.h
index 2072d0fd13..b58f937c57 100644
--- a/scene/gui/tree.h
+++ b/scene/gui/tree.h
@@ -112,7 +112,7 @@ private:
 
 		Cell() {
 
-			custom_draw_obj = 0;
+			custom_draw_obj = ObjectID();
 			custom_button = false;
 			mode = TreeItem::CELL_MODE_STRING;
 			min = 0;
diff --git a/scene/main/canvas_layer.cpp b/scene/main/canvas_layer.cpp
index 4ae018a79a..04cf5c6338 100644
--- a/scene/main/canvas_layer.cpp
+++ b/scene/main/canvas_layer.cpp
@@ -200,7 +200,7 @@ void CanvasLayer::set_custom_viewport(Node *p_viewport) {
 	if (custom_viewport) {
 		custom_viewport_id = custom_viewport->get_instance_id();
 	} else {
-		custom_viewport_id = 0;
+		custom_viewport_id = ObjectID();
 	}
 
 	if (is_inside_tree()) {
@@ -327,7 +327,7 @@ CanvasLayer::CanvasLayer() {
 	layer = 1;
 	canvas = VS::get_singleton()->canvas_create();
 	custom_viewport = NULL;
-	custom_viewport_id = 0;
+
 	sort_index = 0;
 	follow_viewport = false;
 	follow_viewport_scale = 1.0;
diff --git a/scene/main/viewport.cpp b/scene/main/viewport.cpp
index dad2ec4010..748a713110 100644
--- a/scene/main/viewport.cpp
+++ b/scene/main/viewport.cpp
@@ -412,7 +412,7 @@ void Viewport::_notification(int p_what) {
 #ifndef _3D_DISABLED
 				Vector2 last_pos(1e20, 1e20);
 				CollisionObject *last_object = NULL;
-				ObjectID last_id = 0;
+				ObjectID last_id;
 #endif
 				PhysicsDirectSpaceState::RayResult result;
 				Physics2DDirectSpaceState *ss2d = Physics2DServer::get_singleton()->space_get_direct_state(find_world_2d()->get_space());
@@ -532,7 +532,7 @@ void Viewport::_notification(int p_what) {
 							} else {
 								// This Viewport's builtin canvas
 								canvas_transform = get_canvas_transform();
-								canvas_layer_id = 0;
+								canvas_layer_id = ObjectID();
 							}
 
 							Vector2 point = canvas_transform.affine_inverse().xform(pos);
@@ -540,7 +540,7 @@ void Viewport::_notification(int p_what) {
 							int rc = ss2d->intersect_point_on_canvas(point, canvas_layer_id, res, 64, Set<RID>(), 0xFFFFFFFF, true, true, true);
 							for (int i = 0; i < rc; i++) {
 
-								if (res[i].collider_id && res[i].collider) {
+								if (res[i].collider_id.is_valid() && res[i].collider) {
 									CollisionObject2D *co = Object::cast_to<CollisionObject2D>(res[i].collider);
 									if (co) {
 										bool send_event = true;
@@ -594,18 +594,18 @@ void Viewport::_notification(int p_what) {
 #ifndef _3D_DISABLED
 					bool captured = false;
 
-					if (physics_object_capture != 0) {
+					if (physics_object_capture.is_valid()) {
 
 						CollisionObject *co = Object::cast_to<CollisionObject>(ObjectDB::get_instance(physics_object_capture));
 						if (co && camera) {
 							_collision_object_input_event(co, camera, ev, Vector3(), Vector3(), 0);
 							captured = true;
 							if (mb.is_valid() && mb->get_button_index() == 1 && !mb->is_pressed()) {
-								physics_object_capture = 0;
+								physics_object_capture = ObjectID();
 							}
 
 						} else {
-							physics_object_capture = 0;
+							physics_object_capture = ObjectID();
 						}
 					}
 
@@ -613,7 +613,7 @@ void Viewport::_notification(int p_what) {
 						//none
 					} else if (pos == last_pos) {
 
-						if (last_id) {
+						if (last_id.is_valid()) {
 							if (ObjectDB::get_instance(last_id) && last_object) {
 								//good, exists
 								_collision_object_input_event(last_object, camera, ev, result.position, result.normal, result.shape);
@@ -633,7 +633,7 @@ void Viewport::_notification(int p_what) {
 							if (space) {
 
 								bool col = space->intersect_ray(from, from + dir * 10000, result, Set<RID>(), 0xFFFFFFFF, true, true, true);
-								ObjectID new_collider = 0;
+								ObjectID new_collider;
 								if (col) {
 
 									CollisionObject *co = Object::cast_to<CollisionObject>(result.collider);
@@ -651,7 +651,7 @@ void Viewport::_notification(int p_what) {
 
 								if (is_mouse && new_collider != physics_object_over) {
 
-									if (physics_object_over) {
+									if (physics_object_over.is_valid()) {
 
 										CollisionObject *co = Object::cast_to<CollisionObject>(ObjectDB::get_instance(physics_object_over));
 										if (co) {
@@ -659,7 +659,7 @@ void Viewport::_notification(int p_what) {
 										}
 									}
 
-									if (new_collider) {
+									if (new_collider.is_valid()) {
 
 										CollisionObject *co = Object::cast_to<CollisionObject>(ObjectDB::get_instance(new_collider));
 										if (co) {
@@ -2504,7 +2504,7 @@ void Viewport::_gui_remove_from_modal_stack(List<Control *>::Element *MI, Object
 
 	gui.modal_stack.erase(MI);
 
-	if (p_prev_focus_owner) {
+	if (p_prev_focus_owner.is_valid()) {
 
 		// for previous window in stack, pass the focus so it feels more
 		// natural
@@ -2701,14 +2701,15 @@ void Viewport::_drop_physics_mouseover() {
 	}
 
 #ifndef _3D_DISABLED
-	if (physics_object_over) {
+	if (physics_object_over.is_valid()) {
 		CollisionObject *co = Object::cast_to<CollisionObject>(ObjectDB::get_instance(physics_object_over));
 		if (co) {
 			co->_mouse_exit();
 		}
 	}
 
-	physics_object_over = physics_object_capture = 0;
+	physics_object_over = ObjectID();
+	physics_object_capture = ObjectID();
 #endif
 }
 
@@ -2718,7 +2719,7 @@ List<Control *>::Element *Viewport::_gui_show_modal(Control *p_control) {
 	if (gui.key_focus)
 		p_control->_modal_set_prev_focus_owner(gui.key_focus->get_instance_id());
 	else
-		p_control->_modal_set_prev_focus_owner(0);
+		p_control->_modal_set_prev_focus_owner(ObjectID());
 
 	if (gui.mouse_focus && !p_control->is_a_parent_of(gui.mouse_focus) && !gui.mouse_click_grabber) {
 
@@ -3334,8 +3335,6 @@ Viewport::Viewport() {
 	update_mode = UPDATE_WHEN_VISIBLE;
 
 	physics_object_picking = false;
-	physics_object_capture = 0;
-	physics_object_over = 0;
 	physics_has_last_mousepos = false;
 	physics_last_mousepos = Vector2(Math_INF, Math_INF);
 
@@ -3385,7 +3384,6 @@ Viewport::Viewport() {
 	physics_last_mouse_state.mouse_mask = 0;
 	local_input_handled = false;
 	handle_input_locally = true;
-	physics_last_id = 0; //ensures first time there will be a check
 
 	default_canvas_item_texture_filter = DEFAULT_CANVAS_ITEM_TEXTURE_FILTER_LINEAR;
 	default_canvas_item_texture_repeat = DEFAULT_CANVAS_ITEM_TEXTURE_REPEAT_DISABLED;