Draw debug lines for line tracing

Development Programming & Scripting
1

Hi guys,

I am using the GetWorld()->LineTraceSingle() function in CPP code to trace some things. It would be very handy for me to actually see some debug lines drawn by an engine, while a tracing happens. In Blueprints, it is easily done with DrawDebugTrace checkbox, which is present in all the tracing nodes. Is it possible to enable it in C++?

2

Hey, you should be able to do this with the following code:

const FName TraceTag("MyTraceTag");

World->DebugDrawTraceTag = TraceTag

FCollisionQueryParams CollisionParams;
CollisionParams.TraceTag = TraceTag;
...
// Use CollisionParamsto perform your line trace
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3

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DrawDebugLine(
			GetWorld(),
			traceStart,
			hit.Location,
			FColor(255, 0, 0),
			false, -1, 0,
			12.333
		);
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4

Thanks, it works just fine.

5

There’s apparently now a console command, as well. > TraceTag &ltname&gt

Note that async traces will not call the debug draws, however.

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6

I can’t believe they took down the wiki. Probably the worst thing Epic’s ever done.

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7

It does seem like an astonishingly poor deicison, doesn’t it? It seems like most of the content (maybe all of it?) is still available, but finding it is a right ■■■■■

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