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How I can showing USplineComponent in-game?

I create my own AActor and USplineComponent inside this Actor.
Spline creating ok, but it not showing on scene in-game mode

How I can show it? Is it possible? Or USplineComponent is only temporary object for other shapes?

inside the USPlineComponent you have a function called SetDrawDebug(bool bShow), you can use that and also you can change the spline color accesing the memebers: EditorUnselectedSplineSegmentColor, EditorSelectedSplineSegmentColor. But be aware those only work in editor, it will not have any effect in a package.
Maybe you can use splinemesh if you want to display something in a package.

Cheers

you can use blueprint node: Execute Console Command
and write Command: show Splines

then you can see spline in runtime