Reparenting a bakedlightmap causes the engine to crash

[jamie-pate]

Godot version:
3.1
6098a7f

OS/device including version:
Windows 10 Pro 64-bit (10.0, Build 17134) (17134.rs4_release.180410-1804)
GeForce GTX 1070 with Max-Q Design/PCIe/SSE2
(plus Intel(R) UHD Graphics 630 which is disabled)

Issue description:

Generate a baked lightmap with baked textures and then try to move the lightmap into a spatial

	godot.windows.tools.64.exe!Object::call(const StringName & p_name, const Variant & p_arg1, const Variant & p_arg2, const Variant & p_arg3, const Variant & p_arg4, const Variant & p_arg5) Line 866	C++
 	godot.windows.tools.64.exe!BakedLightmap::_assign_lightmaps() Line 667	C++
 	godot.windows.tools.64.exe!BakedLightmap::_notification(int p_what) Line 645	C++
 	godot.windows.tools.64.exe!BakedLightmap::_notificationv(int p_notification, bool p_reversed) Line 91	C++
 	godot.windows.tools.64.exe!Object::notification(int p_notification, bool p_reversed) Line 954	C++
 	godot.windows.tools.64.exe!Node::_propagate_ready() Line 189	C++
 	godot.windows.tools.64.exe!Node::_set_tree(SceneTree * p_tree) Line 2557	C++
 	godot.windows.tools.64.exe!Node::_add_child_nocheck(Node * p_child, const StringName & p_name) Line 1154	C++
 	godot.windows.tools.64.exe!Node::add_child(Node * p_child, bool p_legible_unique_name) Line 1185	C++
 	godot.windows.tools.64.exe!MethodBind2<Node,Node *,bool>::call(Object * p_object, const Variant * * p_args, int p_arg_count, Variant::CallError & r_error) Line 1517	C++
 	godot.windows.tools.64.exe!Object::call(const StringName & p_method, const Variant * * p_args, int p_argcount, Variant::CallError & r_error) Line 942	C++

Tries to call node->call("get_bake_mesh_instance") when node is NULL (result of get_node(light_data->get_user_path(i)))

for (int i = 0; i < light_data->get_user_count(); i++) {
		Ref<Texture> lightmap = light_data->get_user_lightmap(i);
		ERR_CONTINUE(!lightmap.is_valid());

		Node *node = get_node(light_data->get_user_path(i)); // <- node is set to NULL here, i == 1

Steps to reproduce:
Open sample project, move $BakedLightMap node inside $Spatial

Minimal reproduction project:

baked_light_map_crash.zip

[KoBeWi]

The problem here is that lightmap data has nodes stored as NodePaths. To fix this, these paths need to be updated after each move.

I tried to do this, but ultimately got stuck. You can move the BakedLightMap to Spatial2 in the included project, but you can't move it to parent. Here's the patch if someone wants to continue the work: https://pastebin.com/T0NgGkwB

[Calinou]

@jamie-pate Can you reproduce this in the master branch with the new lightmapper?

[jamie-pate]

I can't figure out how to add a meshlib to the bakedlightmap, i generated a meshlib where the meshintance had 'baking' enabled but

See attached 'updated' poc
baked_light_map_crash4.zip

[Calinou]

@jamie-pate Can you (or anyone else) still reproduce this bug in Godot 3.4 or any later release?

If yes, please ensure that an up-to-date Minimal Reproduction Project (MRP) is included in this report (a MRP is a zipped Godot project with the minimal elements necessary to reliably trigger the bug). You can upload ZIP files in an issue comment with a drag and drop.

[jamie-pate]

Yes it still crashes in 3.4.2

bakedlightmap_crash.zip

Here is a stack trace from 3.3.4 (the latest version I have on hand with a debug build)

 
ERROR: get_node: (Node not found: "../MeshInstance" (relative to "/root/EditorNode/@@580/@@581/@@589/@@591/@@595/@@599/@@600/@@601/@@617/@@618/@@627/@@628/@@6060/@@5899/@@5900/@@5901/@@5902/@@5903/Spatial/Spatial2/BakedLightmap").)
   At: scene/main/node.cpp:1371.
ERROR: _assign_lightmaps: Condition "!vi" is true. Continuing.
   At: scene/3d/baked_lightmap.cpp:1206.
ERROR: get_node: (Node not found: "../GridMap" (relative to "/root/EditorNode/@@580/@@581/@@589/@@591/@@595/@@599/@@600/@@601/@@617/@@618/@@627/@@628/@@6060/@@5899/@@5900/@@5901/@@5902/@@5903/Spatial/Spatial2/BakedLightmap").)
   At: scene/main/node.cpp:1371.
handle_crash: Program crashed with signal 11
Dumping the backtrace. Please include this when reporting the bug on https://github.com/godotengine/godot/issues
[1] /lib/x86_64-linux-gnu/libc.so.6(+0x46520) [0x7fbcfcd38520] (??:0)
[2] Object::call(StringName const&, Variant const&, Variant const&, Variant const&, Variant const&, Variant const&) (/home/jpate/src/godot/core/object.cpp:845)
[3] BakedLightmap::_assign_lightmaps() (/home/jpate/src/godot/scene/3d/baked_lightmap.cpp:1198 (discriminator 4))
[4] BakedLightmap::_notification(int) (/home/jpate/src/godot/scene/3d/baked_lightmap.cpp:1173)
[5] BakedLightmap::_notificationv(int, bool) (/home/jpate/src/godot/scene/3d/baked_lightmap.h:106 (discriminator 14))
[6] Object::notification(int, bool) (/home/jpate/src/godot/core/object.cpp:931)
[7] Node::_propagate_ready() (/home/jpate/src/godot/scene/main/node.cpp:197)
[8] Node::_set_tree(SceneTree*) (/home/jpate/src/godot/scene/main/node.cpp:2626)
[9] Node::_add_child_nocheck(Node*, StringName const&) (/home/jpate/src/godot/scene/main/node.cpp:1154)
[10] Node::add_child(Node*, bool) (/home/jpate/src/godot/scene/main/node.cpp:1169)
[11] MethodBind2<Node*, bool>::call(Object*, Variant const**, int, Variant::CallError&) (/home/jpate/src/godot/./core/method_bind.gen.inc:1523 (discriminator 19))
[12] Object::call(StringName const&, Variant const**, int, Variant::CallError&) (/home/jpate/src/godot/core/object.cpp:919 (discriminator 1))
[13] UndoRedo::_process_operation_list(List<UndoRedo::Operation, DefaultAllocator>::Element*) (/home/jpate/src/godot/core/undo_redo.cpp:294 (discriminator 4))
[14] UndoRedo::redo() (/home/jpate/src/godot/core/undo_redo.cpp:338)
[15] UndoRedo::commit_action() (/home/jpate/src/godot/core/undo_redo.cpp:260)
[16] SceneTreeDock::_do_reparent(Node*, int, Vector<Node*>, bool) (/home/jpate/src/godot/editor/scene_tree_dock.cpp:1825)
[17] SceneTreeDock::_nodes_dragged(Array, NodePath, int) (/home/jpate/src/godot/editor/scene_tree_dock.cpp:2524 (discriminator 5))
[18] MethodBind3<Array, NodePath, int>::call(Object*, Variant const**, int, Variant::CallError&) (/home/jpate/src/godot/./core/method_bind.gen.inc:2303 (discriminator 26))
[19] Object::call(StringName const&, Variant const**, int, Variant::CallError&) (/home/jpate/src/godot/core/object.cpp:919 (discriminator 1))
[20] Object::emit_signal(StringName const&, Variant const**, int) (/home/jpate/src/godot/core/object.cpp:1246 (discriminator 1))
[21] Object::emit_signal(StringName const&, Variant const&, Variant const&, Variant const&, Variant const&, Variant const&) (/home/jpate/src/godot/core/object.cpp:1304)
[22] SceneTreeEditor::drop_data_fw(Vector2 const&, Variant const&, Control*) (/home/jpate/src/godot/editor/scene_tree_editor.cpp:1081 (discriminator 8))
[23] MethodBind3<Vector2 const&, Variant const&, Control*>::call(Object*, Variant const**, int, Variant::CallError&) (/home/jpate/src/godot/./core/method_bind.gen.inc:2303 (discriminator 26))
[24] Object::call(StringName const&, Variant const**, int, Variant::CallError&) (/home/jpate/src/godot/core/object.cpp:919 (discriminator 1))
[25] Object::call(StringName const&, Variant const&, Variant const&, Variant const&, Variant const&, Variant const&) (/home/jpate/src/godot/core/object.cpp:846)
[26] Control::drop_data(Vector2 const&, Variant const&) (/home/jpate/src/godot/scene/gui/control.cpp:769 (discriminator 6))
[27] Viewport::_gui_drop(Control*, Vector2, bool) (/home/jpate/src/godot/scene/main/viewport.cpp:1879)
[28] Viewport::_gui_input_event(Ref<InputEvent>) (/home/jpate/src/godot/scene/main/viewport.cpp:2069)
[29] Viewport::input(Ref<InputEvent> const&) (/home/jpate/src/godot/scene/main/viewport.cpp:2923 (discriminator 2))
[30] Viewport::_vp_input(Ref<InputEvent> const&) (/home/jpate/src/godot/scene/main/viewport.cpp:1482)
[31] MethodBind1<Ref<InputEvent> const&>::call(Object*, Variant const**, int, Variant::CallError&) (/home/jpate/src/godot/./core/method_bind.gen.inc:775 (discriminator 12))
[32] Object::call(StringName const&, Variant const**, int, Variant::CallError&) (/home/jpate/src/godot/core/object.cpp:919 (discriminator 1))
[33] Object::call(StringName const&, Variant const&, Variant const&, Variant const&, Variant const&, Variant const&) (/home/jpate/src/godot/core/object.cpp:846)
[34] SceneTree::call_group_flags(unsigned int, StringName const&, StringName const&, Variant const&, Variant const&, Variant const&, Variant const&, Variant const&) (/home/jpate/src/godot/scene/main/scene_tree.cpp:276)
[35] SceneTree::input_event(Ref<InputEvent> const&) (/home/jpate/src/godot/scene/main/scene_tree.cpp:432 (discriminator 6))
[36] InputDefault::_parse_input_event_impl(Ref<InputEvent> const&, bool) (/home/jpate/src/godot/main/input_default.cpp:456)
[37] InputDefault::parse_input_event(Ref<InputEvent> const&) (/home/jpate/src/godot/main/input_default.cpp:273)
[38] InputDefault::flush_accumulated_events() (/home/jpate/src/godot/main/input_default.cpp:692)
[39] OS_X11::process_xevents() (/home/jpate/src/godot/platform/x11/os_x11.cpp:2897)
[40] OS_X11::run() (/home/jpate/src/godot/platform/x11/os_x11.cpp:3639)
[41] /home/jpate/src/godot/bin/godot.x11.tools.64(main+0x131) [0x16f8857] (/home/jpate/src/godot/platform/x11/godot_x11.cpp:57)
[42] /lib/x86_64-linux-gnu/libc.so.6(+0x2dfd0) [0x7fbcfcd1ffd0] (??:0)
[43] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x7d) [0x7fbcfcd2007d] (??:0)
[44] /home/jpate/src/godot/bin/godot.x11.tools.64(_start+0x25) [0x16f8665] (??:?)

[clayjohn]

I can't reproduce this in RC3. Accordingly I am marking this as fixed for 4.0, will re-target to 3.x