Understanding Aqua Windows

[David Egbert]

I'm trying to understand why a stack in Rev has a white background in MacOS
10.1 - 10.2. Most of the apps I've seen for MacOS X have those tiny white
and grey horizontal lines as a background for the main window.  Even
Interface Builder creates windows with lines included.

The last time I had a question about this, list members suggested setting
the background to a png file with the lines.  Now that Panther is out, I'll
need to create another kludge to fix the appearance in Panther. I really
don't like where this is heading, but I want my apps to look and feel like a
real MacOS X app.

Is there an important reason why the lines are omitted?

Regards,

--
Dave Egbert