[Bf-committers] Camera Guides

[Campbell Barton]

> 
> 6. Campell's idea of using (abusing?) Grease Pencil for this has its merits. I'm not entirely sure if the aspect ratio change is such an important use case. Most projects, I'd think, set the aspect ratio at the beginning of the project. Worst case is you have to re-import the guide.

Changes to the aspect ratio of the camera scale keep within the camera
bounds - easy to test, try draw in camera with grease pencil 'View'
enabled.

Beorn Leonard requested this on durian so you could draw on the camera
view to give animation critique without the window size messing up
alignment.