The Clone tool uses the current brush to copy from an image or pattern. It
has many uses: one of the most important is to repair problem areas in
digital photos, by "painting over" them with pixel data from other areas.
This technique takes a while to learn, but in the hands of a skilled user
it is very powerful. Another important use is to draw patterned lines or
curves: see Patterns
for examples.
If you want to clone from an image, instead of a pattern, you must tell
GIMP which image you want to copy from. You do this by holding down the
Ctrl key and clicking in the desired source image. Until you have set the
source in this way, you will not be able to paint with the Clone tool:
the tool cursor tells you this by showing a “forbidden” symbol.
If you clone from a pattern, the pattern is tiled;
that is, when the point you are copying from moves past one of the
edges, it jumps to the opposite edge and continues, as though the pattern
were repeated side-by-side, indefinitely. When you clone from an image
this does not happen: if you go beyond the edges of the source, the Clone
tool stops producing any changes.
You can clone from any drawable (that is, any layer, layer mask, or
channel) to any other drawable. You can even clone to or from the
selection mask, by switching to QuickMask mode. If this means copying
colors that the target does not support (for example, cloning from an RGB
layer to an Indexed layer or a layer mask), then the colors will be
converted to the closest possible approximations.
3.10.1. How to Activate
The Clone tool can be activated from an image menu as
Tools → Paint Tools → Clone;
from the Toolbox by clicking on the tool icon
;
or from the keyboard using the shortcut c, or
S under GIMP-2.10.
3.10.2. Key modifiers
See the Brush Tools
Overview for a description of key modifiers that have the
same effect on all brush tools.
Ctrl
The Ctrl key is used to select the source, if you are
cloning from an image: it has no effect if you are
cloning from a pattern. You can clone from any layer of any
image, by clicking on the image display, with the Ctrl key
held down, while the layer is active (as shown in the Layers
dialog). If the Alignment is set to "Non-aligned" or
"Aligned" in the Tool Options, then the point you click on
becomes the origin for cloning: the image data at that
point will be used when you first begin painting with the
Clone tool. In source-selection mode, the cursor changes to
a crosshair-symbol.
3.10.3. Tool Options
Figure 8.34.
Tool Options for the Clone tool
Note
See the Brush Tools
Overview for a description of tool options that apply to
many or all brush tools.
Pattern
Clicking on the pattern symbol brings up the Patterns
dialog, which you can use to select the pattern to paint
with. This option is only relevant if you are cloning from
a Pattern source.
Source
The choice you make here determines whether data will be
copied from the pattern shown above, or from one of the
images you have open. If you choose "Image source", you
must tell GIMP which layer to use as the source, by
Ctrl-clicking on it, before you can paint with the tool.
Alignment
The Alignment mode sets how the source
position is offset from each brush stroke.
Non-aligned
Aligned
Registered
Above: schematic illustration of the three possible alignment
modes. The mouse cursor is shown as a red rectangle,
and the source point as a black crosshair.
Non-aligned.
In this mode, each brushstroke is treated separately. For
each stroke, the point where you first click is copied from
the source origin; there is no relationship between one
brush stroke and another. In non-aligned mode, different
brush strokes will usually clash if they intersect each
other.
Aligned.
In this mode, the first click you make when painting sets
the offset between the source origin and the cloned result,
and all subsequent brushstrokes use the same offset. Thus,
you can use as many brushstrokes as you like, and they will
all mesh smoothly with one another.
If you want to change the offset, you can do this by
switching to non-aligned mode, painting one stroke, then
switching back to aligned mode. Subsequent strokes will
use the same offset as the first stroke.
Registered.
This mode copies each pixel in the source to the pixel with
the same offset in the target. It is most commonly useful
when you want to clone from one layer to another layer
within the same image. It is also useful when cloning from
a pattern, if you want the left or upper edges of the
pattern to line up precisely with the corresponding edges
of the target layer.
3.10.4. Further Information
Transparency
The effects of the Clone tool on transparency are a bit
complicated. You cannot clone transparency: if you try to
clone from a transparent source, nothing happens to the target.
If you clone from a partially transparent source, the effect is
weighted by the opacity of the source. So, assuming 100%
opacity and a hard brush:
Cloning translucent black onto white produces gray.
Cloning translucent black onto black produces black.
Cloning translucent white onto white produces white.
Cloning translucent white onto black produces gray.
Cloning can never increase transparency, but, unless "keep
transparency" is turned on for the layer, it can reduce it.
Cloning an opaque area onto a translucent area produces an
opaque result; cloning a translucent area onto another
translucent area causes an increase in opacity.
"Filter" brushes
There are a few non-obvious ways to use the Clone tool to
obtain powerful effects. One thing you can do is to create
"Filter brushes", that is, create the effect of applying a
filter with a brush. To do this, duplicate the layer you
want to work on, and apply the filter to the copy. Then
activate the Clone tool, setting Source to "Image source"
and Alignment to "Registered". Ctrl-click on the filtered
layer to set it as the source, and paint on the original
layer: you will then in effect be painting the filtered
image data onto the original layer.
History brush
You can use a similar approach to imitate Photoshop's
"History brush", which allows you to selectively undo or
redo changes using a brush. To do this, start by
duplicating the image; then, in the original, go back to
the desired state in the image's history, either by
undoing or by using the Undo History dialog. (This must
be done in the original, not the copy, because duplicating
an image does not duplicate the Undo history.) Now
activate the Clone tool, setting Source to "Image source"
and Alignment to "Registered". Ctrl-click on a layer from
one image, and paint on the corresponding layer from the
other image. Depending on how you do it, this gives you
either an "undo brush" or a "redo brush".
![[Note]](../images/note.png)
