quarta-feira, 6 de abril de 2016

BP Compendium: LineTraceForObjects


The LineTraceForObjects function tests the collision along a defined line and returns the first found object that belongs to one of the object types specified in the function call.


  • Start: Vector that defines the beginning of the line to be used for the collision test.
  • End: Vector that defines the end of the collision test line.
  • Object Types: Array that contains the types of objects that will be tested in the collision.
  • Trace Complex: Boolean value indicating whether to use complex collisions.
  • Actors to Ignore: Array with the actors that should be ignored in the collision tests.
  • Draw Debug Type: It allows the drawing of the line that is being used in the collision test.
  • Ignore Self: Boolean value that indicates whether the Blueprint that is calling the function should be ignored in the collision test.


  • Out Hit: Structure "HitResult" that contains various information about the collision found.
  • Return Value: Boolean value. If true, it means that a collision was found.

Example Usage

On a blueprint called "AlarmDevice", the LineTraceForObjects function is used to activate an alarm if an object of the Pawn type is detected. The image below shows this example. A macro was used to get the start and end locations of the line.

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To create the array with the type of objects, drag off the pin "Object Types" and choose the "Make Array" option.

The TraceLocations macro looked like this:

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