I've noticed a few screenshots of terminal windows online which show thin highlighted edges around status bars or highlighted lines. In the following example, note the light grey edging around lines 1, 5, and 389:
In this example, notice the yellow edging around the Emacs mode line (status bar):
What is the name of this effect, and is it possible with iTerm 2 under OS X 10.10?
Update
After doing some research and digging into Emacs Customize interface theme code, I found some code that defined the edges. In Emacs parlance, it's called :box, and one of its attributes is line-width. Here's an example of a box line being defined in a theme:
'(modeline ((t (:background "Gray10" :foreground "SteelBlue" :box (:line-width 1 :style none) :width condensed))))
The documentation for :box can be found in the Emacs manual's face attributes documentation, though it doesn't mention how it works, or which terminals are supported.
I started to think that this might be a special feature of GUI versions of Emacs (such as Aquamacs, but I am pretty sure that I have seen screenshots of what appear to be Ubuntu Unity terminal windows with similar box highlights.
Best Answer
The effect you are seeing isn't a terminal window graphical trick, it is gui emacs running in X. You correctly identify the customization to get emacs to draw that, but these are only rendered when emacs is run in X.
To illustrate, I have my mode-line themed with:
and when emacs is run graphically (e.g.
emacs) it is rendered like:and when emacs is run in a terminal (e.g.
emacs -nw) it is rendered as:You can see the pixel border effects that give the raised look defined by the box only render in the gui mode. In terminal mode it is just a flat effect.
Similarly, the pictures you have posted are from gui emacs and the effect is not a property of any terminal emulator, nor is any terminal emulator involved in that rendering.