help: inconsistent framerate IMenu, GFxMovie

[frammiie]

Opening

Hey there, first of all, thank you very much for all the time and effort you've
put in to make this library possible. 💖 It's truly been a great help in achieving
my modding ambitions.

Context

However, whilst using this library in order to create custom menus (Scaleform)
I've noticed some inconsistencies I'm having trouble explaining.
Currently I'm creating menus as following (inside class inheriting from IMenu):

auto menu = static_cast<RE::IMenu*>(this);
auto scaleformManager = RE::BSScaleformManager::GetSingleton();
scaleformManager->LoadMovie(menu, menu->uiMovie, FILE_NAME.data());
assert(success);

And registering it by:

void SkyflashMenu::Register() {
    auto ui = RE::UI::GetSingleton();
    if (ui) {
        ui->Register(MENU_NAME, Creator);
        logger::info("Registered {}", MENU_NAME);
    }
}

RE::stl::owner<RE::IMenu*> SkyflashMenu::Creator() {
    return new SkyflashMenu();
}

And opening it in papyrus via native function

auto msgQ = RE::UIMessageQueue::GetSingleton();
msgQ->AddMessage(SkyflashMenu::MenuName(), RE::UI_MESSAGE_TYPE::kShow, nullptr);

And this works great, the menu pops up, everything is working as intended,
menu flags work, input handling/focus is working fine.

Issue

However there's one glaring problem with this approach, the menu appears to
be running at game refresh rate, instead of the refresh rate defined in the SWF.

Unfortunately, frame rate is very important for my mod and I need it to be constant
in order for some time based coordination.

This is peculiar, because using SKSE to create the menu using OpenCustomMenu in
Papyrus code results into correct behavior, the code is as follows in SKSE:

CustomMenu::CustomMenu(const char* swfPath)
{
    CALL_MEMBER_FN(GFxLoader::GetSingleton(), LoadMovie)(this, &view, swfPath, GFxMovieView::ScaleModeType::kNoBorder, 0.0);
}

---

class GFxLoader {
public:
    // Note: Probably in subclass
    DEFINE_MEMBER_FN(LoadMovie, bool, 0x00ECE790, IMenu* menu, GFxMovieView** viewOut, const char* name, int scaleMode, float backGroundAlpha);
}

This looks similar in how Commonlib-NG does it:

bool BSScaleformManager::LoadMovie(IMenu* a_menu, GPtr<GFxMovieView>& a_viewOut, const char* a_fileName, ScaleModeType a_mode, float a_backGroundAlpha)
{
	using func_t = decltype(&BSScaleformManager::LoadMovie);
	REL::Relocation<func_t> func{ RELOCATION_ID(80302, 82325) };
	return func(this, a_menu, a_viewOut, a_fileName, a_mode, a_backGroundAlpha);
}

Considered Remedies

• Setting menu flags, or any sort of configuration on the IMenu or GFxMovieView
  did not yield to any differences in this problematic frame behavior.

• Manually advancing frame times is an option by selectively calling Advance on the
  GFxMovieView, however this is clunky and a native approach would be more fitting.

Closing Remarks

Unfortunately I'm not that proficient in C++ let alone reverse engineering, so I hope
one of you could help me along the way. The plugin needn't do much but load menu
and handle FxDelegate callbacks.

If you need any further info, or source, Papyrus, and / or ESP files, I would be happy to
provide them to you.

Once again, thank you for your time,
kind regards, frammiie