Need fast way to obtain vertical coordinates of text run

[Bob Sneidar]

I can see why the formattedHeight would not work. It takes into account line wraps as well as line breaks, and a variable or property cannot wrap text. 

Apart from putting the text in question into a hidden field of the exact dimensions, and then checking the formatted height of that, I don't see a way. That may cause serious performance issues. 

Bob


On Nov 27, 2010, at 8:23 AM, Richard Gaskin wrote:

> I need to know the vertical coordinates in pixels of the beginning and end points for a chunk of text in a scrolling field.
> 
> I'm currently using the selectedLoc on the first and last char of the text run, locking the screen and messages while I get that.
> 
> The problem is that I sometimes need to do this a thousand times in succession before I can return control to the user, and this causes significant delay.
> 
> Because the text contains runs of variable height, I can't rely on line counts multiplied by the number of lines to the character in question.
> 
> And because the text may contain Unicode, I can't rely on the formattedText for any of this either.
> 
> And it seems that the formattedHeight works great for the full field, but cannot be used on chunks (I hope I misunderstand that, but I couldn't get any such syntax to work).
> 
> And yes, the field resizes with the window, so I need to also recalculate on resizeStack as well.
> 
> 
> I briefly experimented with the mouseChunk, hoping that I could set and then restore the screenMouseLoc as needed, and while it sometimes works it really screws up the pointer interaction, no matter how cleverly I try to hide the cursor during that brief moment; and worse, the mouseChunk only returns a value when the mouse is actually over text, and sometimes blank lines may be there instead.
> 
> I'm hoping there's some magically fast way to get those measurements without having to actually touch the field contents, which is apparently an inherently slow action (relatively speaking).
> 
> Anyone here know of such magic?
> 
> --
> Richard Gaskin
> Fourth World
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