I have a general question for some of you advanced expression / script writers. Why is it computationally and or logistically such a tall order for AE to return the height or width in pixels of a text layer which takes into account text size / scale etc. I've employed the sample image hack before, but I'm just curious from a technical stand point why this isn't easier to query?
I think only the Adobe engineers could answer your question. Scripting has sourceRectAtTime(), which works very well, but I have no idea what it would take to implement the same functionality in expressions. It's been requested, but it wouldn't hurt to add your vote: