Mmm, it’s not quite as simple as that, I’ve got a zillion of these little components many of which are showing the same image. Caching just the one component isn’t getting the speed up! I’ll look at what that function does tho maybe…
Whahaha - this is harder than it ought to be without buying a retina display … just discovered it down renders with tiny images … maybe I need to apply another transform here somewhere
IME on mac it will switch at some point while you are dragging, you can see it on the other display with an alpha applied either up or down scaled accordingly then it will switch the display resolution and switch which side of the window has no alpha and which side has an alpha applied - in other words the OS handles this for you and you will only ever have one display resolution at a time (I believe). Unless there is some way to enable it there is no way to actually display the plug-in across two monitors, once you release from dragging the window, it will only show the part of the window that is displayed on the screen the resolution is applicable to. If you are not already use Quartz Debug to simulate a retina display.
IIRC on Mac you can also simulate a retina monitor using the regular System Preferences: just open the Monitor settings and choose whatever HiDPI resolution appears in the list that shows when you don’t choose to use the default resolution for the monitor.