1. apireference
2. effects
3. trail

WidthScale

Property of: Trail

Value Type: NumberSequence

(distance between trail's attachment0 and attachment1 in studs) * (the value of WidthScale)

Code Samples

Scaling a Trail's Width

This example demonstrates the the effects of setting and changing a trail’s WidthScale property.

In order to do this, we must first create a BasePart, part, which will be the parent of the trail.

Then, we create two attachments, attachment0 and attachment1, both parented to part. The positions of these two attachments, more importantly the distance between them, determines where the trail is drawn as part moves. It is this distance that used with the WidthScale value to determine the width of the trail’s drawn segments.

For these attachments to create a trail as described, we create a new Trail and parent it to part. We then connect attachment0 to Trail/Attachment0 and attachment1 to Trail/Attachment1.

In this example, we rely on an array containing two values sizes = {0.25, 0.75} to alternate between two WidthScale properties. To alternate, we use a variable i and the formula (i+1)%2 to flip the value of i between 0 and 1. Lastly, we set the WidthScale value using a DataType/NumberSequence to set the property to the ith element (1 or 2) from sizes.

Finally, to demo the property’s affect on the trail’s lifetime, the example relies on TweenService’s TweenService/Create to move part back and forth. As the part moves, the trail’s segment lifetime (existing and new) grows and shrinks as the property changes.

-- Create a new BasePart
local part = Instance.new("Part")
part.Parent = game.Workspace
part.Anchored = true
part.Position = Vector3.new(0,5,0)

-- Create 2 attachments
local attachment0 = Instance.new("Attachment")
attachment0.Name = "Attachment0"
attachment0.Parent = part
attachment0.Position = Vector3.new(-2,0,0)

local attachment1 = Instance.new("Attachment")
attachment1.Name = "Attachment1"
attachment1.Parent = part
attachment1.Position = Vector3.new(2,0,0)

-- Create a new Trail
local trail = Instance.new("Trail")
trail.Parent = part
trail.Attachment0 = attachment0
trail.Attachment1 = attachment1

-- Tween part to display trail
local TweenService = game:GetService("TweenService")

local dir = 15
local i = 1
local sizes = {0.25, 0.75}
while true do
	i = (i+1)%2
	print(i)
	trail.WidthScale = NumberSequence.new(sizes[i+1])
		
	dir = dir*-1
	local goal = {}
	goal.Position = part.Position + Vector3.new(0,0,dir)
 
	local tweenInfo = TweenInfo.new(5)
	local tween = TweenService:Create(part, tweenInfo, goal)
 	tween:Play()

	wait(5)
end