I have a background image I am trying to scale to cover the entire screen. I attach a UIStretch script to it, set the Style to 'Both' and leave the relative size at 1,1. I have a UIRoot with a manual height set to 480 and automatic unchecked. It works in that my background image always covers at least the extents of my game window, but unless I'm at a resolution of 320x480 the image seems to scale beyond the bounds of my game window.
When I switch the game window to use 640x960, the background image scales to what looks to be roughly double the size of the screen. The scaled size of the background image in inspector is 640x960 (which is what one would expect), but if I view the background image in the Scene window, it clearly extends beyond the widgets that I have anchored to the sides of the game window.
This is ok in that it covers the entire screen, but when I try to use this stretched background as a Widget Container in a UIAnchor, my anchors end up being off-screen. Same thing if I use my UIPanel parent as a UIPanel Container.
The reason I am trying to use a Widget or Panel container for my anchors is because of a sorting issue I am trying to fix in which I am using background sprites behind a dynamically loaded UITexture with more sprites layered on top (despite my best efforts to convince our artists that this would be problematic) but my sorting problem probably warrants creating a different post.
My main question is, should the background be scaling beyond the bounds of my screen based on how I'm using the UIStretch script and my UIRoot? Is this a bug, or is this just how it is supposed to work?