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Simple Raytrace distance = 0

I've written a function which raytraces directly downwards from the VR camera (to detect if the player is currently ducking), but the distance is returning 0 in the log.

I've avoided self- collision with AddIgnoredActor(this), and I can't detect what the raytrace is hitting.

Attempting to print out the name of the actor/component that gets hit in the log results in a crash (most likely because nullptr).

     // Ray Casting downwards from the HMD
     FHitResult* hitResult = new FHitResult();
     FVector hmdLocation = CameraComp->GetComponentLocation();
     FVector endTrace = hmdLocation + (FVector(0.0f, 0.0f, -90.0f) * 50.0f);
     FCollisionQueryParams traceHmdDistanceParams = FCollisionQueryParams(FName("HMD Duck Raycast"), true, this);
     traceHmdDistanceParams.AddIgnoredActor(this);     // Ignore ourselves in the collision detection
     GetWorld()->LineTraceSingleByChannel(*hitResult, hmdLocation, endTrace, ECC_WorldStatic, traceHmdDistanceParams); // Start Raycast
     
     // Show HMD raycasts in the world
     DrawDebugLine(GetWorld(), hmdLocation, endTrace, FColor::Red, true);
 
     if (hitResult->Distance <= duckingHeight)
     {
         UE_LOG(LogTemp, Warning, TEXT("Player HIT actor / Distance to ground: %f"), hitResult->Distance);
     }

Bit stuck here, any help appreciated.

Product Version: UE 4.21
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asked Mar 09 '19 at 09:39 PM in C++ Programming

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DJRD4465
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Fixed. Multiple issues, the floor Static Mesh didn't have collision so the trace wasn't hitting anything. I've simplified the function also: https://i.imgur.com/H0knBxY.png

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answered Mar 10 '19 at 01:06 AM

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DJRD4465
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