Currently, it is very difficult to determine where a CoreGui element is on screen.
The easiest way to explain is with an example:
Say I want to have a piece of Gui at the bottom of the screen, above the backpack.
I have a game that utilizes the backpack, a coreGui element, and simply want to put extra information above it.
Unfortunately, it is very difficult to actually figure out where the backpack is! All coreGui elements scale in various ways, depending on things like the resolution, and type of device. Due to CoreGui’s nature of being hard to access, this means it is seemingly impossible to accurately place UI elements in way that is a complementary to CoreGui. If it’s difficult to know and access CoreGui, and there are no easier methods to locate the extents of various CoreGui elements, we end up with extremely ugly UI elements that overlap CoreGui and can never act in unison with it.
Which is, in fact, exactly what we do see happening - It isn’t that hard to find examples of games that have UI attempting to live in harmony with Roblox’s coreGui, but absolutely failing to.
This in my opinion is something that is very bizarre, we should have had access to this likely long, long ago. Some function that lets you input a coreGui and get it’s position/size on screen currently would allow developers to have much prettier Gui in a lot of places, as it’d allow them to keep on standardized roblox UI but also implement their own right beside it.
This has something that has been talked about before, as shown in this thread, so I think it’s about time we were finally able to come out of the darkness and are able to see what we’re doing.