7.0

Turn on trace mode using the toggle button on the infobar. Draw with
the Freehand tool over a photo and you should see that the line tries to
follow edges in the image.
You can also turn trace mode on and off while you are actively drawing a line, by pressing the T
key. The mouse pointer changes to indicate whether trace mode is on or off. This allows you, for
example, to turn off trace mode when you are drawing over a complex part of an image where there is no
obvious edge for trace mode to follow.
Commit points
You'll often notice as you draw along an edge in a photo that sometimes the last few pixels of the line
you've drawn will 'jump' around as it searches for different routes. When there is more than one possible
route, move the mouse pointer around and see the edge jump between them. You can 'commit' the edge
at any time by pressing the space bar
when a correct route has been found. Then continue and trace mode will find more routes between the
last commit point and the mouse pointer.
Commit points are automatically added for you every 50 screen pixels, because you don't normally want
to re-route the line more than that distance from where you are currently drawing.
Erasing
As mentioned above, whether tracing is on or off you can erase the last part of the line you've drawn by
holding down the Shift key and moving the mouse pointer back to an earlier part of the line. The line is
erased from that point to the end of the line.
Complex images
Few real world photos have objects with obvious unambiguous edges that can easily be followed by
trace mode. There is often texture in the objects themselves or in the background which mean that trace
mode will find many different candidate edges. Zoom into difficult parts of photos to get more control
over the trace and use the space bar to enter manual commit points more often, the more complex the
image. And press T to turn tracing on and off as you move between parts of an image that are easy to
trace and parts that are not.
Cutting out objects from photos
To cut out part of a photo you can either draw an ordinary shape over the top of the photo and then use
the combine shapes operations in the Arrange menu to cut the photo with the shape (see the Shape
Handling chapter
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