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This lecture, we're going to fix the issue where the player is slowly sliding down the ladder.

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When we want the player to kind of stay stationary, when they get onto the ladder.

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The way we're going to do that is messing around with gravity.

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So let me just show you something here.

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If I was to turn the gravity scale on the player to zero and then run to the ladder up there, the play

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is not going to drop at all.

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There's no gravity whatsoever.

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Now I've said it to zero, which means that also if we run around in the world, I'm not going to be

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dropping.

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So I want in code to say the gravity scale is zero when the player is standing on the ladder.

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Now I know that's not how the world works.

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If you climb up a ladder to get to the roof of your house, the gravity doesn't go to zero, because

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if you fall off your ladder bump, you're going to fall off and hurt yourself.

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But in this case, we're using that mechanism as a way to say, don't slide up and down the ladder.

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So this will be our challenge to stop the player sliding, set the starting gravity on the player rigid

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body to the rigid bodies current gravity.

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So you'll need a way of finding out when we start our game what is the current gravity for the rigid

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body?

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And then to set a variable, which is to say this is the gravity when we first start our game and then

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when the player is on the ladder, set the gravity to zero.

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And obviously when the player is not on the ladder, then set the gravity back to what the starting

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gravity is supposed to be.

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So there you go.

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There's a bit of a different sort of challenge.

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Pause the video.

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Take that on.

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See back here when you're done.

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We'll be here in our player movement script up at the very top.

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I'm going to create myself another cached variable, which will be of type float, and that float will

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call gravity scale at start.

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Nice big name should make sense when we look back at this in the future and within my start method,

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I need to define that as something.

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So gravity scale start is going to be equal to my rigid body because this is where we find out gravity.

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Just a reminder, if you're like, how do you even know to do that?

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So if we go back to Rigid Body is the thing that controls gravity for the player.

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For this particular game object, you can see the gravity scale is eight.

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So it's rigid body 2d dot something to do with gravity.

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So if we jump in here, my rigid body, which is the way that we've cached our reference to the rigid

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body 2d so my rigid body dot gravity scale semicolon and that now case equals eight.

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But if we go and change our gravity scale in here, then it will be updated nicely.

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If we're not currently touching the ladder that we want the gravity to be the same as the starting gravity.

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So I'm going to expand this out now.

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My nice little neatly compartmentalized return.

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We'll put this on its own new line, new area return will stay at the bottom because if you're not touching

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it, we still want to return and not allow the player to climb.

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But I'll add something in here which will be my rigid body.

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Gravity scale is going to equal gravity scale at start.

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So I just want to make sure we've got the right gravity.

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So if you're not touching the ladder, then use the gravity scale that we had at the start.

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However, if you are currently climbing, then we'll pop down here.

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My rigid body dot gravity scale equals what equals zero.

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Don't give the player any gravity and it's a flow.

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We'll put f there just to be complete and thorough.

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We'll save that and see if we've got our desired effect.

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Gravity should be normal unless we're touching the ladder, in which case it should be zero.

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Click on play jumping works.

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Okay, climb the ladder works.

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Okay.

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And we're stopped here.

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You can see if we look over in our rigid body on the player, it's zero and I'm on the ladder, I jump

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off the ladder, it goes back up to eight.

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Perfect.

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So there we go.

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We've got the right behavior that we wanted when we're on our ladder.

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We can't we're not slowly drifting down.

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We don't have our animation set up just yet.

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So I think it might be time to do that in the next lecture.

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Okay.

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See you in the next lecture.