Link to timelines doc for c++?

Development Programming & Scripting
1

Hello everyone! I am just now diving into C++ from blueprints, and I use timelines a lot in blueprints and was wondering if they were in C++, and if so is there a doc I could use?

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2

Hey Designer102-

You’ll want to look into using timers in code. The class for timers is Runtime/Engine/Public/TimerManager.h and there is a short tutorial on setting up an actor that uses a timer:

https://docs.unrealengine.com/latest/INT/Programming/Tutorials/VariablesTimersEvents/1/index.html

Let me know if this info helps.

Cheers

3

The timer wont work for what I am trying to do, have a variable change overtime once a function is called, I am thinking of using a curve asset, is there a doc for that or any tips and tricks?

4

Unfortunately using a timeline in blueprints does not translate to code cleanly. If you are trying to change the value of a variable based on time then your best bet would be to use a time or to edit the variable in the Tick function so it will update with each tick.

5

I was actually planning to make it so a boolean is set to true in a function, then in the tick it will check for if the boolean is true and if so it will add to a float and if the float is over or at my wanted amount it will set the boolean to false, would that work?

6

That would work. Just keep in mind that while the bool is true, the float will increase every tick.

7

After trying this before I thought I give this timeline in c++ another shot. There are still some old answers here on answerhub which show how to use timelines in c++ with the actor’s own tick function. But actually it also works withouth using the tick of the actor. I had to use AddInterpFloat() at runtime to get this to run.

This answer should work for you!

//.h

UPROPERTY()
UTimelineComponent* ScoreTimeline;

UPROPERTY()
UCurveFloat* fCurve;

FOnTimelineFloat InterpFunction{};

//.cpp

//Constructor:

static ConstructorHelpers::FObjectFinder<UCurveFloat> Curvy(TEXT("CurveFloat'/Game/Blueprints/NotSoImportant/CurveFloatBP.CurveFloatBP'"));
if (Curvy.Object) {
	fCurve = Curvy.Object;
}

ScoreTimeline = ObjectInitializer.CreateDefaultSubobject<UTimelineComponent>(this, TEXT("TimelineScore"));

InterpFunction.BindUFunction(this, FName{ TEXT("TimelineFloatReturn") });

//Then inside BeginPlay for example:

ScoreTimeline->AddInterpFloat(fCurve, InterpFunction, FName{ TEXT("Floaty") });
ScoreTimeline->Play(); // or PlayFromStart() etc, can be called anywhere in this class

//And Finally your callback function:

void AYourClass::TimelineFloatReturn(float val)
{
 //Your float val from curve returns here
}

}

I made a wiki page about this here:

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8

U actually can use Timeline c++ in the same way as in blueprint withouth using a boolean or tick of the actor where the timeline is in. See my answer below.

9

I had to add UFUNCTION to the declaration of the “TimelineFloatReturn” function but otherwise this seems to work perfectly, thanks!

10

Hey @spaceharry, how would create your own curve in this, but where do you add value for it?

11

Hey @spaceharry, how would create your own curve in this, but where do you add value for it?

12

This still works beautifully today. I much prefer this, without having to call the progress function from within Tick, which never seemed right!

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