The scan wave material master has several boolean parameters. The configuration used in the examples uses the world time minus an offset to advance the wave. Whenever the player enters the visualizers trigger volume the blueprint sets the start offset to the current time and the wave starts from the beginning. You can also toggle looping if you only want one wave instead of steady pulses. Scan Duration then tells the material how long a wave should take to complete.
The scan wave can also be used by directly setting a percent value. To enable this toggle the “Use time for scanning” flag to off and set the material parameter “scan percent”.
The code of the visualizer is documented you can open up the blueprint and look at what it does when overlapping an actor.
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