How can I fix the issue where the camera is not properly fixed on the object?

Help and Feedback Scripting Support
#1

1. What I want to achieve?

Hello Roblox developers,
I’m currently working on a catalog avatar editor GUI for my game, but I’ve run into a camera-related issue. I’d like to fix this problem.

2. What is the issue?

I found and modified a script to position Camera.CameraSubject on the left side of the screen, and while it works to some extent, the BillboardGui elements are floating on the screen, and the camera is not properly fixed on the character.

Reference video: https://www.youtube.com/watch?v=Cw__iFmgf2o

Code:

# AvatarEditorController.luau

function AvatarEditorController:SetEditingAvatar(avatar: Model?)
	StateStore:SetState({
		editingAvatar = avatar,
	})

	local currentCamera = workspace.CurrentCamera

	if not avatar then
		Resize.Stop()
		return
	end

	LocalPlayerUtils:SetMovement(false)
	setCoreGuiEnableds(false)
	Resize.Start()

	currentCamera.CameraSubject = avatar
end

# Resize.luau
local RunService = game:GetService("RunService")

local Camera = workspace.CurrentCamera

local Resize = {}

Resize.Position = UDim2.fromScale(0.3, 0)
Resize.Size = UDim2.fromScale(1, 1)

local function UDim2Absolute(udim2)
	local viewSize = Camera.ViewportSize

	return Vector2.new((udim2.X.Scale * viewSize.X) + udim2.X.Offset, (udim2.Y.Scale * viewSize.Y) + udim2.Y.Offset)
end

function Resize._computePosition()
	local viewSize = Camera.ViewportSize
	local aspectRatio = viewSize.X / viewSize.Y

	local offset = UDim2Absolute(Resize.Position)
	local position = offset / viewSize

	local hFactor = math.tan(math.rad(Camera.FieldOfView) / 2)
	local wFactor = hFactor * aspectRatio

	return position.X * wFactor * 2, position.Y * hFactor * 2
end

function Resize._computeSize()
	local size = UDim2Absolute(Resize.Size) / Camera.ViewportSize

	return size.X, size.Y
end

function Resize._getOffset()
	local x, y = Resize._computePosition()
	local w, h = Resize._computeSize()

	return CFrame.new(0, 0, 0, w, 0, 0, 0, h, 0, x, y, 1)
end

local beforeFovMode = Camera.FieldOfViewMode

function Resize.Start()
	Camera.FieldOfViewMode = Enum.FieldOfViewMode.MaxAxis

	RunService:BindToRenderStep("ViewportCamera", Enum.RenderPriority.Camera.Value + 1, function()
		Camera.CFrame = Camera.CFrame * Resize._getOffset()
	end)
end

function Resize.Stop()
	RunService:UnbindFromRenderStep("ViewportCamera")
	Camera.FieldOfViewMode = beforeFovMode
end

return Resize