|Revision $Revision: 1.43 $
Intelligent Scissors tool icon in the Toolbox.
The Intelligent Scissors tool is an interesting piece of equipment: it has
some features in common with the Lasso, some features in common with the
Path tool, and some features all its own. It is useful when you are trying
to select a region defined by strong color-changes at the edges. To use
the Scissors, you click to create a set of "control nodes" at the edges of
the region you are trying to select. The tool produces a continuous curve
passing through these control nodes, following any high-contrast edges it
can find. If you are lucky, the path that the tool finds will correspond
to the contour you are trying to select.
Each time you left-click with the mouse, you create a new control point,
which is connected to the last control point by a curve that tries to
follow edges in the image. To finish, click on the first point (the cursor
changes to indicate when you are in the right spot). You can adjust the
curve by dragging the control nodes, or by clicking to create new control
nodes. When you are satisfied, click anywhere inside the curve to convert
it into a selection.
Be sure not to click inside the curve until you are completely done
adjusting it. Once you have converted it into a selection, undoing takes
you back to zero, and you will have to to start constructing the curve
again from scratch if you need to change it. Also be sure not to switch
to a different tool, or again all of your carefully created control
nodes will be lost. (But you still can transform your selection into a
path and work it with the Path tool.)
Unfortunately, there seem to be some problems with the edge-following
logic for this tool, with the result that the selections it creates tend
to be pretty crude in a lot of cases. A good way to clean them up is to
switch to QuickMask
mode, and use paint tools to paint in the problematic parts. On the whole,
most people find the Path tool to be more useful than the Scissors,
because, even though it does not have the intelligent edge-finding
capability, the paths it produces persist until you delete them, and can
be altered at any time.
The Intelligent Scissors can be activated from an image
or from the keyboard using the shortcut i.
-> -> ;
from the Toolbox by clicking on the tool icon
2.7.2. Key modifiers (Defaults)
The Scissor tool does not have any special key modifiers,
only the ones that affect all selection tools in the same way.
See Selection Tools for
help with these.
Tool Options for the Intelligent Scissors
See Selection Tools for
help with options that are common to all these tools. Only
options that are specific to the Intelligent Scissors
tool are explained here.
Show Interactive Boundary
If this option is enabled, dragging a control node during
placement will indicate the path that will be taken by the
selection boundary. If it is not enabled, the node will be shown
connected to the previous node by a straight line while you are
dragging it around, and you won't see the resulting path until you
release the pointer button. On slow systems, if your control nodes
are far apart, this may give a bit of a speed-up.