Loading Progress

Anything that keeps the loading screen up can report how far it has come, as a value from 0 to 1. The manager combines the values, and your widget reads the total with Get Loading Progress on the Loading Screen Manager.

Reading the progress in the widget

Call Get Loading Progress on the Loading Screen Manager, for example in a binding on a Progress Bar.

• It returns a value from 0 to 1 while something reports progress.
• It returns -1 when nothing reports progress. Show a throbber instead of a progress bar in that case.
• It never goes backwards while the loading screen is shown, so the bar doesn't jump back when a new task starts.
• It is set to 1 when nothing needs the loading screen anymore, for example during Show Loading Screen Additional Secs.
• It is set back to -1 when the loading screen is hidden.

When several objects report progress, the total is their average.

Reporting progress from a task

Call Set Progress on a Loading Process Task while it works. A task that never calls Set Progress is not counted.

ULoadingProcessTask* Task = ULoadingProcessTask::CreateLoadingScreenProcessTask(this, TEXT("Loading save game"));
Task->SetProgress(0.5f);

Reporting progress from the interface

Implement Get Loading Progress in the Loading Process Interface on the Game State, a Player Controller, one of their components or a Watcher. Return true and set Out Progress to report a value. Return false to not be counted.

virtual bool GetLoadingProgress(float& OutProgress) const override
{
	OutProgress = static_cast<float>(NumLoaded) / NumToLoad;
	return true;
}

info

The progress is updated each frame while the game thread is running. A map that loads with Open Level blocks the game thread, so the value stands still during the map load itself. Use the progress for what happens after the map has loaded, for example streaming, data from a server or spawning.