Fun with hover text

Does anyone know what 'rules' there are about hovertext showing through things?

I was working with someone who needed (pre html on a prim) to use hovertext for a particular application, which was essentially a vendor system. Sadly the hovertext from one thing would "show through" for quite some distance. The vendor happened to have a prim low down and when we experimented with that (more out of desparation) although well within the previous view range the text didn't show through.

Rather confusingly a similar approach right next to this one DID show through. I think, but I'm not sure, the main difference was that the prim on the 'successful' one was wholly in-front of the rest of the object it was linked to whereas on the 'unsuccessful' one the prim was lower than the remainder of the object.

Can anyone tell me? It might just be worth sticking into the wiki if there's some kind of rationale that anyone knows?

Have you played around with the "alpha" for the hovertext? When I did, it doesn't so much affect it as transparency, but as view distance.. I don't know. Not too sure I understand the question.

Yes, I played with alpha. It makes a slight difference (going from alpha=1.0 to 0.1 I could still read the text quite some distance away, albeit at a slightly lower distance).

I was really asking if anyone had any hard information about how hover text is drawn and particularly about how the client selects whether or not to draw it when the prim generating it isn't visible.

My observations imply that having a prim as part of a linked object that is entirely obscured (from the my view point) by the rest of the object blocks the hover text even with alpha=1.0 and close to. Other arrangements allow the hover text to be drawn even through a number of intervening prims at various distances, until the distance is so great that you can't resolve the hover text without blockages. Is this what other people have observed? Is it known and documented anywhere?

that sounds about right whith what ive noticed

I've noticed a lot of hover text that appears when the object is behind you by several meters.

It is just above axis of each object where floating text appears. Object's extension doesn't matter. Unless the blocking object's axis is short of the axis of floating text showing one, you can see the text.