Need help scripting a skydive system

[SonicFrontiers011 (tsuki)]

You can write your topic however you want, but you need to answer these questions:

1. What do you want to achieve? Keep it simple and clear!
   Hello developers! I am currently designing a skydive game, where you fall of from a point and you maintain your speed and slowly make your way down to the bullseye.
2. What is the issue? Include screenshots / videos if possible!
   I’m using VectorForce, and I’m not seeing a difference in the system when I do:

VectorForce.Force = Vector3.new(0, HumanoidRootPart:GetMass() * workspace.Gravity, 0)

Why does the difference only become noticeable on the y-axis after a force of 1500?
3. What solutions have you tried so far? Did you look for solutions on the Developer Hub?
I have tried using LinearVelocity, but the character just didn’t move for some reason. I found this post saying that I should VectorForce could work for wind resistance:

@Sir_Highness

Yes, and adding the vector force in the up direction to make them fall slower (and deleting that when they are done falling). This is kind of like the wind resistance, pushing them up so they reach a constant terminal velocity and not keep accelerating to infinite speed.

[hylas16 (Hylian16)]

You get more control if you edit the HumanoidRootParts AssemblyLinearVelocity manually in a RunService loop

With this you could just keep the Y velocity at a constant speed and keep or boost the other axes’ velocities to achieve the sky diving effect, without having to bother with adjusting vector forces.

[hya123456h (KingBob)]

It’s affected because 1500 is over the total mass of the character not just the humanoid root part

[BendsSpace]

@SonicFrontiers011

where you fall of from a point and you maintain your speed and slowly make your way down to the bullseye

Here is what I would recommend:

• Use a LinearVelocity to control the falling speed. LinearVelocities apply forces to make an assembly match a certain speed. You can set the LinearVelocity.ForceLimitMode to PerAxis, then set the LinearVelocity.MaxAxesForce to something like (0, 99999999999, 0). This makes it so the speed on the Y axis is controlled by the LinearVelocity.VectorVelocity (e.g. you could use a value of (0, -40, 0) here to fall at -40 studs per second).
• Play a skydiving animation on the character. (No need to actually rotate the character, just make an animation that does it for you!)
• To determine when the player hits the ground, use downwards raycasts every frame, a Humanoid.Touched connection, or use a Humanoid.StateChanged connection, so that you can stop the animation and destroy the linear velocity when this happens.

[SonicFrontiers011 (tsuki)]

So uhm, how do I make like the turning radius feel a bit heavier and have the player tilt to the side they move? I’m not exactly sure how to explain, but I think you understand what I mean.

[SonicFrontiers011 (tsuki)]

That makes a lot of sense now. I didn’t take that into account before.

[BendsSpace]

You could have Humanoid.AutoRotate turn off, then control the direction the player faces using an AlignOrientation.

I would program the AlignOrientation to slowly point the character towards the direction they’re moving.

Then, I would also program something to scale the character’s walk speed based on how close their MoveDirection is to the direction they’re facing (e.g. use Humanoid.MoveDirection:Dot(HumanoidRootPart.CFrame.LookVector) for how close the two directions are).

[SonicFrontiers011 (tsuki)]

What does :Dot() do and how will I use it in this situation?

[SonicFrontiers011 (tsuki)]

I also have this boolean call ‘RoundEnded’ which checks if the round is over. So, like this:

					table.clear(Winners) -- clears the table of previous winners.
					hasClearedTable = true
					RoundEnded.Value = true
					task.wait(3)
					RoundEnded.Value = false

RoundEnded.Changed:Connect(function(newValue)
	if newValue == true then
		LinearVelocity.Enabled = false
		Humanoid.JumpPower = defaultJumpPower
		ContextActionService:UnbindAction("SpeedBoost")
		if SkydiveAnimationTrack.IsPlaying then
			SkydiveAnimationTrack:Stop(0.5)
		end
	end
end)

Is this what I should be doing?

[BendsSpace]

For two unit vectors, the Dot between them returns a value between [-1, 1], depending on how close the two vectors are to the same direction. If they point exactly the same direction, it returns 1, if they point exactly the opposite, it returns -1, if they are perpendicular, it returns 0.

[BendsSpace]

Yeah that looks good.

[SonicFrontiers011 (tsuki)]

I might need to reduce the task.wait(3) because it feels a bit delayed.

[SonicFrontiers011 (tsuki)]

Do you know why the force isn’t applying when the player is skydiving if they press J?

HumanoidRootPart.AssemblyLinearVelocity = HumanoidRootPart.CFrame.UpVector * appliedImpulse

[BendsSpace]

That looks correct. I would use :ApplyImpluse instead though. Also make sure that appliedImpulse is something like desiredVelocityChange * hrp.AssemblyMass

[SonicFrontiers011 (tsuki)]

Oh… I just set it to -50. Let me change it real quick.

[SonicFrontiers011 (tsuki)]

" The sum of the mass of all the parts in this part’s assembly. Parts that are Massless and are not the assembly’s root part will not contribute to the AssemblyMass."

This makes sense. And it was what @hya123456h said earlier I believe?

[SonicFrontiers011 (tsuki)]

It still doesn’t work, but I’ll keep trying. Maybe it’s because there’s already an AssemblyLinearVelocity being applied.

[BendsSpace]

I made most of a sky diving system based on Tear’s of the Kingdom’s:

Here is a place file:
SkydiveSystem.rbxl (58.9 KB)

Currently it still uses the default character movement. I’m planning on writing up some aerodynamic (inspired) equations to make the horizontal motion be based on the air hitting the diver then probably open sourcing it.

I’m also planning on swapping the default falling animation for this one:

Cartoony Fall

Feel free to use what’s there though. I don’t have any timeline for finishing it so please don’t wait on me.

[Scottifly]

Why not use FluidDynamics? It’d allow you to create a more realistic gliding system.

Introducing FluidForceSensor: Enhancing Precision and Usability for Aerodynamic Design

Hi Creators, We’re excited to announce the release of FluidForceSensor, a powerful new tool for creators working with aerodynamics. This sensor, which works both in Studio & in-experience, allows you to measure forces, torques, and the center of pressure for aerodynamic assemblies, making it easier than ever to design, debug, and fine-tune your creations. What is the FluidForceSensor? The FluidForceSensor is a new instance that enables creators to measure the aerodynamic properties of an asse…

[SonicFrontiers011 (tsuki)]

That looks nice! I will take some notes of that and see what I can change/add to my system.

Also, whenever the player jumps this fires and it causes some strange things to happen:

Skydive.OnClientEvent:Connect(function()
	print("skydive fired")
	Humanoid.StateChanged:Connect(function(oldState, newState)
		print("state changed")
		if newState == Enum.HumanoidStateType.Freefall then
			LinearVelocity.VectorVelocity = Vector3.new(0, -diveSpeed, 0)
			LinearVelocity.Enabled = true
			Humanoid.JumpPower = 0
			ContextActionService:BindAction("SpeedBoost", Boost, true, Enum.KeyCode.J, Enum.KeyCode.ButtonY)
			ContextActionService:SetTitle("SpeedBoost", "Boost")
			ContextActionService:SetPosition("SpeedBoost", UDim2.new(0.2, 0, 0.5, 0))
		end
	end)
end)

Do I even have to fire a RemoteEvent at this point, just to catch when the player is actively skydiving? Or Can I just check when the state is changed.