This is an attempt to make the lifecycle of wrapped objects clearer.
Godot keeps track of bindings' userdata for each object it creates.
This allows allocating the memory of the wrapper only once per object
even if that object is passed multiple times between binding code and
godot code.
The binding information is composed of multiple functions, this includes
a callback for when the userdata is to be allocated (called once) and
for when the userdata is to be deallocated (again, called once).
When allocating data with "memnew" we set the object bindings during the
postinitialize phase, but surely we shouldn't do that when allocating
the userdata as a result of bindings callback themselves.
Additionally, since we let Godot handle (and track) raw memory
allocation and de-allocation, we need to manually call the deconstructor
of the wrapper class during the free callback, to ensure that its
non-trivial members are correctly de-initialized.
This commit changes the platform detection order to detect mingw
compiling for windows (which defines `__GNUC__`).
This commit also wraps the definition around a guard so it can be
overridden via a define at build-time.
The returned value "ret" may be nullptr in which case the code would crash because "object_get_instance_binding" can't be called on nullptr input.
This should be very easy to reproduce, I encountered it pretty much any time I called a method that returned Ref<Something>. E.g.:
Ref<GeometryInstance3D> instance;
instance.instantiate();
instance.get_mesh(); // Crash because no mesh was set for the instance and the returned value was nullptr.
Proper initialization for godot-cpp classes with memnew.
Extension classes (i.e. the `GDCLASS` macro) behave differently from
regular wrapped classes, and requires Godot to initialize them during
object construction.
This commit update the GDCLASS macro to not create/destroy the instance
during the bindings callback, but during the extension callbacks.
When setting the object instance, the bindings instance is set to the
pointer of the extension instance so that it can later be retrieved
normally via `object_get_instance_bindings`.
Fabio Alessandrelli
DNKpp
bruvzg
Rémi Verschelde
Alessandro Famà
Teodor Potancok
Melissa Geels
Gilles Roudière
Marc Gilleron
Zhehang Ding
ondy-personal
Lukas Tönne
Rémi Verschelde
Bradley Clemetson
Bastiaan Olij