Dealing with Key Meshes in InstaLOD for Unreal Engine

About this document

After the initial authorization, InstaLOD needs to refresh the license periodically. If InstaLOD can't validate the license when running mesh operations, a key model is generated. This can happen when the workstation doesn't have access to https://api.InstaLOD.io or multiple instances of InstaLOD are trying to access the license file, typically located in "C:\ProgramData\InstaLOD" on windows or "/Users/Shared/InstaLOD/" on macOS.

Hardcoding credentials

If this issue occurs often, we suggest hardcoding the credentials into the plugin. This can be done with the following code:

if (!InstaLODAPI->IsHostAuthorized())
{
    const ANSICHAR* const username = "<InstaLOD username>";
    const ANSICHAR* const password = "<InstaLOD password>";
    if (!InstaLODAPI->AuthorizeMachine(username, password))
    {
        UE_LOG(LogInstaLOD, Fatal, TEXT("Failed to authorize InstaLOD with error: %s"), UTF8_TO_TCHAR(InstaLODAPI->GetAuthorizationInformation()));
    }
}

This would need to be done in InstaLODModule.cpp which resides in 'InstaLODMeshReduction/Source/InstaLODMeshReduction/Private' at the end of void FInstaLODModule::StartupModule().

In the case that potential key meshes might already have been saved in the UE4 cache, the only solution is to clean the cache and let Unreal Engine regenerate the assets automatically. You can find more information about UE4s DDC here: https://docs.unrealengine.com/en-US/ProductionPipelines/DerivedDataCache/index.html .