|
 |
|
| |
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
.
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. Activating the tool
You can activate this tool in several ways:
-
From the image menu through
→ → .
-
By clicking on the tool icon
in Toolbox.
-
By pressing the C keyboard shortcut.
3.10.2. Key modifiers (default)
See the Brush tools key
modifiers 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 Alignment is set to
None, Aligned, or
Fixed in 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 reticle
cross symbol
.
Normally, tool options are displayed in a window attached under the
Toolbox as soon as you activate a tool. If they are not, you can access
them from the image menu bar through
→ → which opens the option window of the selected tool.
-
Mode; Opacity; Brush; Scale; Brush Dynamics; Fade out; Apply Jitter;
Hard Edges
-
![[Note]](images/note.png)
|
Note |
|
See the Brush Tools
Overview for a description of tool options that apply to many or
all brush tools.
|
-
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.
-
Image
-
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.
If you check Sample merged it's what
you “see” (color made with all the layers of
a multi-layer image) that's cloned. If it's unchecked,
only the selected layer is cloned. For more information
see the glossary entry Sample Merge.
-
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.
-
Alignment
-
The Alignment mode defines the relation between the brush
position and the source position.
In the following examples, we will use a source image where the
sample to be cloned will be taken, and a destination image where
the sample will be cloned (it could be a layer in the source
image)
-
None
-
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.
Example below: At every new brush stroke, the source goes
back to its first position. The same sample is always
cloned.
-
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, select a new source origin
by clicking with the Ctrl key pressed.
In the example below, at every new brush stroke, the source
keeps the same offset it had with the previous brush stroke.
So, there is no cloning offset for the first brush stroke.
Here, for the following strokes, the source ends up out of
the source image canvas; hence the truncated aspect.
-
Registered
-
The “Registered” mode is different from the
other alignment modes. When you copy from an image, a
Ctrl-click will register a source layer. Then painting in a
target layer will clone each corresponding pixel (pixel with
the same offset) from the source layer. This is useful when
you want to clone parts of an image from one layer to
another layer within the same image. (But remember that you
can also clone from one image to another image.)
At every brush stroke, the source adopts the position of the
mouse pointer in the destination layer. In the following
example, the destination layer is smaller than the source
layer; so, there is no truncated aspect.
-
Fixed
-
Using this mode you will paint with the source origin,
unlike the modes None or
Aligned even when drawing a line. The
source will not be moved.
See that the source remains fixed. The same small sample is
reproduced identically in a tightened way:
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”.
|
|
|
