Detecting if something is in front an object

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:bust_in_silhouette: Asked By Yeldham
:warning: Old Version Published before Godot 3 was released.

How do I detect if something is in front of an object in a top-down environment? I know it has to do with the dot product, but I don’t know how to implement it.

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:bust_in_silhouette: Reply From: quijipixel

To use the dot product you need a direction vector and the position of the other object, then you get the substraction (vector from object A to object B, or BA for short) and get the dot product of the BA vector to the direction vector. If this value is greater than 0 then the B object is facing towards the A object. You can see that on the VectorMath section of Godot’s Documentation.

You can always use an Area2D as the view area for the object.