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‫Hello and welcome.

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‫In this lecture, we're going to be adding a tag to an object that's currently being grabbed.

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‫So if I grab this gargoyle f eight out and have a look at the Gargoyle statue, you can see it now has

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‫this grabbed tag attached.

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‫If I go ahead and release the gargoyle and have a look at it again, you can see the tag goes away.

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‫So this will communicate to other gameplay things in our scene that the gargoyle is currently being

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‫held and that it shouldn't be snatched away.

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‫Let's dive in and see how to implement this.

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‫So at the moment when we drop the gargoyle in to the trigger area, what happens is the trigger area

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‫kind of snatches the gargoyle away and doesn't wait for us to finish letting go.

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‫And this is because the trigger area has no notion of the fact that that gargoyle is being held by a

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‫grabber.

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‫So to do that, to give the to communicate to the trigger components that we have got some kind of hold

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‫on the gargoyle, we're again going to use tags, except this time we're going to add and remove them

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‫programmatically and we're going to be doing this over in the grabber.

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‫CP So let's open that up in the Visual Studio code and have a look at our grab function where currently

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‫what we're doing with the component that we hit is that we are simply going ahead and waking all the

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‫rigid bodies.

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‫So what we want to do now is add a new tag.

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‫How do we do that?

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‫Well, first of all, we need to get hold of the actor in question.

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‫So we should do hit result dot get actor and then using that actor pointer so arrow we can look for

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‫tags.

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‫Now tags is a property that is a t array.

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‫So we've seen t arrays, that's a t array of f names.

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‫So we need to be able to manipulate this tray to add and remove tags from it.

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‫So let's go back to the tray and see what's available to us.

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‫If we search for ADD, you can see that there is a bunch of functionality where you can pass in the

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‫element type, which in our case is an F name and it adds a new item to the end of the array and does

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‫all the jobs that it needs to do to make sure that you have space for it.

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‫If you search for remove, there's a whole bunch of things that mention removing, but only a few methods

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‫that actually have the name remove.

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‫And you can see it removes many instances of an item as there are in the array.

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‫So what's that saying?

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‫It's saying if it has that item in the array, it will remove all of the instances of that item from

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‫the array.

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‫So if you put in multiple tags with the same name, it would remove them all.

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‫Whereas if you look further down there is a remove at and this would remove an element, a specific

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‫index.

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‫Now we definitely want the former rather than the latter because we want to remove by the tag name which

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‫we're going to just call grabbed.

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‫So let's start with adding, we'll go back into Visual Studio code and we've got this tags array.

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‫So what we can do with it is we can simply do a dot because it's not a pointer, it's the actual array.

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‫Then we're going to call add and then we're going to add an F name which we can just use a string for

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‫called grabbed like so.

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‫So this should when we grab the object, add a tag to it that says it has been grabbed, let's go ahead

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‫and compile this and check.

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‫Once that's done, let's go ahead and hit play and try and pick up the gargoyle like so then I'm going

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‫to hit F eight to possess and we should be able to select our gargoyle actor, scroll down and have

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‫a look at its actor tags.

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‫So that's in the actors section under advanced.

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‫We can have a look at the tags.

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‫We can see there are three tags there.

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‫Currently we have got unlock one and then grabbed and then grabbed again because we didn't remove it.

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‫We actually if we grab it twice by accident, which I think I must have done, then it adds the tag

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‫twice.

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‫So I'd like you to remove the tag when we release the actor.

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‫So you're going to get hold of the actor in release remembering that you can use get owner to get hold

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‫of the owning actor.

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‫If you've got hold of a component already, you can get the tag array from that actor and then you can

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‫call remove on it with the tag that you want to remove from the array.

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‫And finally go ahead and test it out, see if it works.

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‫Pause the video and have a go.

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‫Okay.

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‫Welcome back.

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‫Right.

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‫So I'm going to stop playing, go back into Visual Studio code and we're going to go in to the release

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‫where we've got this get grabbed component and not equal to null.

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‫And then we're releasing things.

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‫Well, we need to get the ground component, but we need to get owner of that grabbed component as well.

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‫So arrow from the get go component, get owner to keep this line short, I'm going to put it in a variable.

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‫A actor grabbed actor equals handle get grabbed component get owner.

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‫Then with that grabbed actor, we can do grabbed actor arrow tags and then we're going to do tags or

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‫remove and we're going to remove, grabbed, make sure that you have the exact same string for the two

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‫semicolon at the end of the line and let's recompile.

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‫So now if I hit play near the gargoyle, I'll go and pick him up.

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‫Hit F eight.

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‫Let's have a look at the gargoyle, see what tags we've got.

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‫We've got the grabbed tag.

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‫Only one of them this time, which is good.

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‫Now if we repossess and click in and we drop release, then we can f eight again, select that gargoyle

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‫statue, have a look at tags, and sure enough, the grab tag has gone away.

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‫So this will give us an excellent mechanism to communicate to other components in the world that this

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‫gargoyle, hey, it's mine.

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‫It's currently grabbed.

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‫Don't try and take it away from me and lock it into any kind of receiving triggers.

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‫And that's what we're going to do in the next lecture.

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‫So I'll see you there.