|Revision $Revision: 1.25 $
You will probably have it happen many times that you need to place
something in an image very precisely, and find that it is not easy to do
using a mouse. Often you can get better results by using the arrow keys on
the keyboard (which move the affected object one pixel at a time, or 25
pixels if you hold down the Shift
key), but GIMP also provides you with two other aids to make positioning
easier: grids and guides.
Image used for examples below
Image with default grid
Each image has a grid. It is always present, but by default it is not
visible until you activate it by toggling
Image Window Appearance
page of the Preferences dialog. (Note that there are separate settings
for Normal Mode and Fullscreen Mode.)
in the image menu. If you want grids to be present more often than not,
you can change the default behavior by checking "Show grid" in the
The default grid appearance, set up when you install GIMP, consists of
plus-shaped black crosshairs at the grid line intersections, with grid
lines spaced every 10 pixels both vertically and horizontally. You can
customize the default grid using the
Default Image Grid
page of the Preferences dialog. If you only want to change the grid
appearance for the current image, you can do so by choosing
from the image menu: this brings up the
Configure Grid dialog.
A different grid style
Not only can a grid be helpful for judging distances and spatial
relationships, it can also permit you to align things exactly with
the grid, if you toggle
page of the Preferences dialog, but most people seem to be happy
with the default value of 8 pixels. (Note that it is perfectly
possible to snap to the grid even if the grid is not visible. It
isn't easy to imagine why you might want to do this, though.)
in the image menu: this causes the pointer to "warp" perfectly to
any grid line located within a certain distance. You can
customize the snap distance threshold by setting "Snap distance"
Image with four guides
In addition to the image grid, GIMP also gives you a more flexible
type of positioning aid: guides. These are
horizontal or vertical lines that you create by clicking on one of
the rulers and dragging into the image. You can create as many
guides as you like, positioned whereever you like. To move a guide
after you have created it, activate the Move tool in the Toolbox (or
press the M key), you can then click and drag a
guide. To delete a guide, simply drag it outside the image. Holding
down the Shift key, you can move everything but a guide, using the
guides as an effective alignment aid.
As with the grid, you can cause the pointer to snap to nearby
guides, by toggling
in the image menu. If you have a number of guides and they are
making it difficult for you to judge the image properly, you can
hide them by toggling
It is suggested that you only do this momentarily, otherwise you
may get confused the next time you try to create a guide and
don't see anything happening.
If it makes things easier for you, you can change the default behavior
for guides in the
Appearance page of the Preferences dialog. Disabling "Show
guides" is probably a bad idea, though, for the reason just given.
Another use for guides: the Guillotine plugin can use guides
to slice an image into a set of sub-images.
See also Guides in Glossary.