What is wrong with this velocity code?

[pevdn (bigman)]

I want to achieve when I press the “P” button, it will make the part go forward using AssemblyLinearVelocity. My code I have is:

local p = game.Players
local lp = p.LocalPlayer
local UIS = game:GetService("UserInputService")
local ws = game.Workspace

UIS.InputBegan:Connect(function(input)
	if input.KeyCode == Enum.KeyCode.P then
		ws.Part.AssemblyLinearVelocity = Vector3.new(20,0,0)
	end
end)

I do not get any errors from it, but the part moves when the game runs. What could be happening? Thanks in advance!

Edit: I forgot to mention that this is in a LocalScript parented to StarterCharacterScripts

[RMofSBI]

Does the part have its linear velocity set to anything in the property window? If so , set it to 0,0,0.

[pevdn (bigman)]

Although it did have a value set in it and I set it to 0 once again, it now does not move at all. I have to assume that the problem is in my code.

[RMofSBI]

Yes you atleast know that the code is the issue, we can go from there.

[RMofSBI]

Ok read this post’s solution:

Body Velocity does not work on client

Hi, I am trying to make a ball that you can move around with the arrows. I am using body velocity to move the ball, but I have found some unexpected behavior. When I change the body velocity on the server, the ball moves with no problem. Here is what it looks like. -https://gyazo.com/3b69e4039c0731380e62c66ce6b4dafa Unforunately, when I change it via a local script I experience some odd behavior. Most of the time the ball will not move at all, while other times it will move a little and then st…

[pevdn (bigman)]

After modifying my code to match that post’s solution, it still does not move. My newer code now is:

local p = game.Players
local lp = p.LocalPlayer
local UIS = game:GetService("UserInputService")
local ws = game.Workspace

game.Players.ChildAdded:Connect(function(plrAdded)
	game.Workspace.Part:SetNetworkOwner(plrAdded)
	UIS.InputBegan:Connect(function(input)
		if input.KeyCode == Enum.KeyCode.P then
			ws.Part.AssemblyLinearVelocity = Vector3.new(20,0,0)
		end
	end)
end)

[RMofSBI]

No those modifications wont work… and i believe you will need remote events to move things in server from a local script.

[pevdn (bigman)]

I modified it once again to use remote events, yet it still does not work.

Localscript:

local replstore = game.ReplicatedStorage
local addVel = replstore.AddVel
local p = game.Players
local lp = p.LocalPlayer
local UIS = game:GetService("UserInputService")
local ws = game.Workspace
local part = game.Workspace.Part

UIS.InputBegan:Connect(function(input)
	if input.KeyCode == Enum.KeyCode.P then
		addVel:FireServer(part)
	end
end)

ServerScript (Located in ServerScriptService):

local replstore = game.ReplicatedStorage
local addVel = replstore.AddVel

addVel.OnServerEvent:Connect(function(player, part)
	game.Workspace.Part.AssemblyLinearVelocity = Vector3.new(30,0,0)
end)

[dthecoolest]

You will also need network ownership in order to apply physics changes.

Ex:

Is there any way to make this knockback smoother/less laggy?

So I have done some testing since this is a frequent recurring and interesting topic. So I have done testing with the server network ownership method, the only cons I see is that it’s not smooth for the victim perspective. Video testing, with 0.25 seconds incoming network replication lag: Video uses: .AssemblyLinearVelocity += knockbackVelocity (simple instantaneous velocity method) Humanoid platformstand (to disable humanoid physics interference) Network ownership on serve…

[pevdn (bigman)]

I added a network ownership statement into it, but it is still not working.

local replstore = game.ReplicatedStorage
local addVel = replstore.AddVel

game.Players.PlayerAdded:Connect(function(plr)
		addVel.OnServerEvent:Connect(function(player, part)
			game.Workspace.Part:SetNetworkOwner(plr)
			game.Workspace.Part.AssemblyLinearVelocity = Vector3.new(30,0,0)
	end)
end)

[RMofSBI]

Try this:

local replstore = game.ReplicatedStorage
local addVel = replstore.AddVel


addVel.OnServerEvent:Connect(function(player, part)
	game.Workspace.Part:SetNetworkOwner(player)
	game.Workspace.Part.AssemblyLinearVelocity = Vector3.new(30,0,0)
end)

[pevdn (bigman)]

I just have one more question about this solution…

After I have pressed P and it goes foward, I cannot use it again.

[RMofSBI]

@pevdn

UIS.InputBegan:Connect(function(input)
	if input.KeyCode == Enum.KeyCode.P then
		addVel:FireServer(part)
	end
end)

I believe you will do this:

local connection
connection = UIS.InputBegan:Connect(function(input)
	if input.KeyCode == Enum.KeyCode.P then
		addVel:FireServer(part)
	end
connection:Disconnect()
end)

[pevdn (bigman)]

This seems to make the whole script not work.

LocalScript:

local replstore = game.ReplicatedStorage
local addVel = replstore.AddVel
local p = game.Players
local lp = p.LocalPlayer
local UIS = game:GetService("UserInputService")
local ws = game.Workspace
local part = game.Workspace.MovingObject

local connection
	connection = UIS.InputBegan:Connect(function(input)
	if input.KeyCode == Enum.KeyCode.P then
		addVel:FireServer(part)
	end
	connection:Disconnect()
end)

ServerScript:

local replstore = game.ReplicatedStorage
local addVel = replstore.AddVel

addVel.OnServerEvent:Connect(function(player, part)
	game.Workspace.MovingObject:SetNetworkOwner(player)
	game.Workspace.MovingObject.AssemblyLinearVelocity = Vector3.new(100,0,0)
end)

[RMofSBI]

Do you mean once the part moves it does not stop and so you cannot use the P again since the part is moving now?

[pevdn (bigman)]

No, I mean that the part goes, but then when I press P once again it does not go and does not give me an error.

[RMofSBI]

You set the velocity and so nothing will stop its velocity unless you script it in to do that… its not like a throttle input or a tool that disables once you activate it.

[pevdn (bigman)]

I think you misunderstood what I meant. I meant that when I press P, the part goes, slows down and stops. I then press P once again and it does not move.