If you are using planes with an advanced dynamic texture on it, you could check if the planes intersect.
If you are using a full screen ADT then I don’t think there’s any way to know if a control is intersecting another control except by checking yourself that the 2D bounding box of each control is intersecting.
There’s actually a simple version and a complex version. Depending if you want to account for rotation. Option one is assuming you will never rotate your box and then you can just use the control._currentMeasure to get the center, width and height.
For the complex one (aka accounting for the rotation) We do a bit of math in the engine to get the bounding box: Let’s a look at the invalidateRect() function inside of control.ts .
In summary we get the _currentMeasure and transformToRef to get the measure in global space. Then measure.CombineToRef to get the bounding box.
Side note: It’s a bit expensive approach if you want to test every box control against every box control.