surface.DrawTexturedRectRotated problem

I’m currently working on my first GLua menu and I’ve been trying to put some animation on my logo and there’s something weird that I’ve noticed.
The logo looks fine when the angle is set to 0 but as soon as it changes, it gets pixaleted which looks awful.
I’m using a .png file and surface.SetMaterial(Material(path)) for it.
Is there a way to get rid of this ugly pixelated logo?

Firstly, please don’t do this:

surface.SetMaterial( Material( path ) ) 

The wiki warns that Material is an expensive function to call every frame. Please do this:

local mat = Material( path )
-- Later in a HUDPaint hook:
surface.SetMaterial( mat )

Anyway, the actual problem may be that you need a smooth parameter:

local mat = Material( path, "smooth" )