The Single Row Marquee Tool
creates one pixel high and all image wide row selections:
To select a row In the Toolbox, select the Single
Row Marquee
Tool and click on the image.
While New selection
option choosen on the Optionsbar
by creating new selection you delete existing selection.
To add a row to existing selection you have
either to choose Add to selection
option on the Options bar or to press (and hold)
[Shift] key while selecting.
To subtract a row from existing selection you
have either to choose Subtract from selection
option on the Options bar or to press [Alt]
key while selecting.
Like with other selecting tools you can intersect new row
with existing selection (either by choosing Intersect
with selection
option on the Options bar or by pressing [Shift+Alt]
keys while selecting. However the result will be the new selection.
While New selection option is chosen and
the point of cursor is within selected area
the tool looks like this
and can move selection (ie. borders of selected area and not
image content).
While New selection option is chosen you
can also move selection using keyboard
cursor keys.
* On the animation
above colors were inverted just to make selected area visible
(it turns black).
** Selection techniques explained
in detail in The Skills