How do I test for a Persistent Actor in a BP?

jonbellini · February 16, 2016, 11:25pm

Using the Rollerball Template, I want to use the Event Hit to give “damage” to the ball. So basically anything it comes in contact with. BUT the Ground is in constant contact with the ball… how do I make this exception?

I tried everything but I can’t reference Ground (which is a StaticActorMesh) within my Ball BP.

Any ideas?

aureon · February 17, 2016, 2:01am

First, Hit triggers in two cases:

A physics hit happens
A kinematic sweep fails

Are you using physics, or kinematic movement (Projectile, etc) ?

aureon · February 17, 2016, 2:45am

You’re going to need to divide the actors in your level, somehow: Blacklisting or whitelisting, but you’re going to need to store information about it some way.

You can:

use a GameplayTag, and only apply damage against tagged actors
Use WorldStatic for the “map” components, and then only apply the damage if the collider collision response is NOT a WorldStatic
Trigger damage if the hit normal isn’t in the same direction as gravity

Either way, you’re going to need to tell your game what is a “Map” and what is a normal collider.

aureon · February 17, 2016, 3:18am

Use “Actor has tag” on the Other (which is the actor), or “Component has tag” on the Other Comp (which is the component, ie. the mesh)

aureon · February 17, 2016, 3:30am

Glad it worked, please accept this answer for tracking purposes:
You’re going to need to divide the actors in your level, somehow: Blacklisting or whitelisting, but you’re going to need to store information about it some way.

You can:

use a GameplayTag, and only apply damage against tagged actors
Use WorldStatic for the “map” components, and then only apply the damage if the collider collision response is NOT a WorldStatic
Trigger damage if the hit normal isn’t in the same direction as gravity

Either way, you’re going to need to tell your game what is a “Map” and what is a normal collider.

jonbellini · February 17, 2016, 2:29am

its the roller ball template…(NewProject>RollerBall) I go into PhysicsBallBP and there’s a Hit Event that’s already triggering CanJump (bool) - so basically whenever the ball hits the ground it’s allowing you to jump again. I want to use that event to give the ball damage (a variable) but since the Ground triggers a “Hit” it takes damage continuously… I just want every other Physics object to trigger a “Hit” and then “damage” the ball, everything but the Floor (Ground)

jonbellini · February 17, 2016, 3:16am

The tag doesn’t seem to work… it returns an array of Actors… I need a True or False… i.e. is it the Floor? else take damage…

jonbellini · February 17, 2016, 3:28am

ahh excellent… ActorHasTag from Other didn’t work, but Component has Tag from Other Comp worked…

thanks!!!