Dual Render Scaling Patch

--Around line 60, we have this:

--Only update camera CFrame when scope CameraPart moves
GetPropertyChangedSignal(CameraPart, "CFrame"):Connect(function()
    Camera.CFrame           = CameraPart.CFrame
    local vector = WorldToScreenPoint(PlrCamera, ScreenPart.Position)
    if vector.X ~= RenderFrame.Position.X.Offset then
        RenderFrame.Position    = udim2(0,vector.X,0,vector.Y)
        RenderFrame.Size        = udim2(0,(100/vector.Z)/(PlrCamera.FieldOfView/75),0,(100/vector.Z)/(PlrCamera.FieldOfView/75))

    end
end)

--We need to fix the RenderFrame.Size line to this:

RenderFrame.Size        = GetObjectScreenSize(ScreenPart)

--You'll run into an issue! You don't have that function yet!
--Somewhere above this section (I did it directly above the "Only update camera CFrame..." comment)
--You'll need to add this function:

local function GetObjectScreenSize(Object)
    local cframe,size = Object.CFrame,Object.Size

    --Area is base times height
    local tR = WorldToScreenPoint(PlrCamera, cframe * v3(-size.x/2,  size.y/2, -size.z/2))
    local bR = WorldToScreenPoint(PlrCamera, cframe * v3(-size.x/2, -size.y/2, -size.z/2))
    local tL = WorldToScreenPoint(PlrCamera, cframe * v3( size.x/2,  size.y/2, -size.z/2))

    local base      = (v3(tR.X,tR.Y,0)-v3(tL.X,tL.Y,0)).magnitude
    local height    = (v3(tR.X,tR.Y,0)-v3(bR.X,bR.Y,0)).magnitude

    return UDim2.new(
        0,
        base,
        0,
        height
    )
end

--Next, we need to account for rotation in the GUI itself
GetPropertyChangedSignal(CameraPart, "CFrame"):Connect(function()
    Camera.CFrame           = CameraPart.CFrame
    local vector = WorldToScreenPoint(PlrCamera, ScreenPart.Position)
    if vector.X ~= RenderFrame.Position.X.Offset then
        RenderFrame.Position    = udim2(0,vector.X,0,vector.Y)
        RenderFrame.Size        = GetObjectScreenSize(ScreenPart)
        --Rotation compensation (Fun to say out loud!)
        RenderFrame.Rotation    = ScreenPart.Orientation.Z
    end
end)

--Then we need to map to the face of the screen, not the center
GetPropertyChangedSignal(CameraPart, "CFrame"):Connect(function()
    Camera.CFrame           = CameraPart.CFrame
    local vector = WorldToScreenPoint(PlrCamera, ScreenPart.CFrame*v3(0,0,-ScreenPart.Size.Z/2)) --Use this instead!
    if vector.X ~= RenderFrame.Position.X.Offset then
        RenderFrame.Position    = udim2(0,vector.X,0,vector.Y)
        RenderFrame.Size        = GetObjectScreenSize(ScreenPart)
        RenderFrame.Rotation    = ScreenPart.Orientation.Z
    end
end)


--Perfect! Your product should now look like this:

local function GetObjectScreenSize(Object)
    local cframe,size = Object.CFrame,Object.Size

    --Area is base times height
    local tR = WorldToScreenPoint(PlrCamera, cframe * v3(-size.x/2,  size.y/2, -size.z/2))
    local bR = WorldToScreenPoint(PlrCamera, cframe * v3(-size.x/2, -size.y/2, -size.z/2))
    local tL = WorldToScreenPoint(PlrCamera, cframe * v3( size.x/2,  size.y/2, -size.z/2))

    local base      = (v3(tR.X,tR.Y,0)-v3(tL.X,tL.Y,0)).magnitude
    local height    = (v3(tR.X,tR.Y,0)-v3(bR.X,bR.Y,0)).magnitude

    return UDim2.new(
        0,
        base,
        0,
        height
    )
end

--Then we need to map to the face of the screen, not the center
GetPropertyChangedSignal(CameraPart, "CFrame"):Connect(function()
    Camera.CFrame           = CameraPart.CFrame
    local vector = WorldToScreenPoint(PlrCamera, ScreenPart.CFrame*v3(0,0,-ScreenPart.Size.Z/2))
    if vector.X ~= RenderFrame.Position.X.Offset then
        RenderFrame.Position    = udim2(0,vector.X,0,vector.Y)
        RenderFrame.Size        = GetObjectScreenSize(ScreenPart)
        RenderFrame.Rotation    = ScreenPart.Orientation.Z
    end
end)