Move _scene_particles_set_view_axis to new static function to allow call to be done on render thread, preventing multi threaded error on compute shader execution.

[Bonkahe]

Resolves #99025 by calling the function particles_set_view_axis on the render thread.
The error would occur when the number of instances in the tree went over 1k, resulting in the thread_cull_threshold being exceeded, this resulted in the multi-threaded culling method being called for particle effects, this then subsequently called particles_set_view_axis which was now being called from a thread other than the render thread, and would immediately throw errors for trying to execute a compute shader on any thread other than the render thread (this only occurred either the draw_order or transform_align settings were changed on a GPUParticles3D).

I initially was going to just call it directly using a callable_mp style call, but it would not allow it because it's calling it on a singleton, so what I did was create a static function within RendererSceneCull to call the function same as before, then called that static function using call_on_render_thread and passing it a callable_mp_static constructor.
If there is a way to do it in a single line that would be preferable, but I had no small amount of issues trying to get that work, and couldn't find any examples elsewhere of that functionality to reference.

[clayjohn]

I am not super familiar with the callable syntax. This seems like the right workaround if we can't create a callable in this situation

@KoBeWi Is it correct that we won't be able to create a callable that calls RSG::particles_storage->particles_set_view_axis() from renderer_scene_cull?

[KoBeWi]

I don't see why the Callable couldn't be created.
Try callable_mp(RSG::particles_storage, &RendererParticlesStorage::particles_set_view_axis).

[Bonkahe]

I don't see why the Callable couldn't be created. Try callable_mp(RSG::particles_storage, &RendererParticlesStorage::particles_set_view_axis).

I tried that, results in this error:

.\core/object/callable_method_pointer.h(116): error C2039: 'get_instance_id': is not a member of 'RendererParticlesStorage' .\servers/rendering/storage/particles_storage.h(36): note: see declaration of 'RendererParticlesStorage' .\core/object/callable_method_pointer.h(116): note: the template instantiation context (the oldest one first) is servers\rendering\renderer_scene_cull.cpp(3022): note: see reference to function template instantiation 'Callable create_custom_callable_function_pointer<RendererParticlesStorage,RID,const Vector3&,const Vector3&>(T *,const char *,void (__cdecl RendererParticlesStorage::* )(RID,const Vector3 &,const Vector3 &))' being compiled with [ T=RendererParticlesStorage ] .\core/object/callable_method_pointer.h(129): note: see reference to class template instantiation 'CallableCustomMethodPointer<RendererParticlesStorage,void,RID,const Vector3 &,const Vector3 &>' being compiled .\core/object/callable_method_pointer.h(113): note: while compiling class template member function 'CallableCustomMethodPointer<RendererParticlesStorage,void,RID,const Vector3 &,const Vector3 &>::CallableCustomMethodPointer(T *,R (__cdecl RendererParticlesStorage::* )(RID,const Vector3 &,const Vector3 &))' with [ T=RendererParticlesStorage, R=void ] .\core/object/callable_method_pointer.h(129): note: see the first reference to 'CallableCustomMethodPointer<RendererParticlesStorage,void,RID,const Vector3 &,const Vector3 &>::CallableCustomMethodPointer' in 'create_custom_callable_function_pointer'

[ydeltastar]

The implementation is correct because non-static callables can only be used with an Object but RendererParticlesStorage is a plain class.
It needs to run format to fix CI.

[Bonkahe]

The implementation is correct because non-static callables can only be used with an Object but RendererParticlesStorage is a plain class. It needs to run format to fix CI.

I am having an absolute nightmare trying to get clang to make any sense, but I think I may have gotten it sorted, I will see when the workflow runs.

[clayjohn]

Looks good to me!

The syntax to make callables work kinda sucks, but its not your fault and this is the correct way to fix things, so oh well

[Repiteo]

Thanks! Congratulations on your first contribution! 🎉

Or, err, second contribution? Got in two back-to-back, gotdayum

[Bonkahe]

Thanks! Congratulations on your first contribution! 🎉

Or, err, second contribution? Got in two back-to-back, gotdayum

Lol Thank you!