A gradient is a set of colors arranged in a linear order. The most basic use of gradients is by the Gradient tool, sometimes known as „gradient fill tool“: it works by filling the selection with colors from a gradient. You have many options to choose from for controlling the way the gradient colors are arranged within the selection. There are also other important ways to use gradients, including:
Each of GIMP's basic painting tools allows you the option of using colors from a gradient. This enables you to create brushstrokes that change color from one end to the other.
This filter is in the Colors menu, and allows you to „colorize“ an image, using the color intensity of each point with the corresponding color from the active gradient (the intensity 0, very dark, is replaced by the color at most left end of the gradient, progressively until the intensity is 255, very light, replaced by the most right color of the gradient. See 8.39 – „Mapování z přechodu“ for more information.
When you install GIMP, it comes presupplied with a large number of interesting gradients, and you can add new ones that you create or download from other sources. You can access the full set of available gradients using the Gradients dialog, a dockable dialog that you can either activate when you need it, or keep around as a tab in a dock. The „current gradient“, used in most gradient-related operations, is shown in the Brush/Pattern/Gradient area of the Toolbox. Clicking on the gradient symbol in the Toolbox is an alternative way of bringing up the Gradients dialog.
Many quickly examples of working with gradient (for more information see Gradient Tool):
Put a gradient in a selection:
Choose a gradient.
With the Blend Tool click and drag with the mouse between two points of a selection.
Colors will distributed perpendicularly to the direction of the drag of the mouse and according to the length of it.
Painting with a gradient:
You can also use a gradient with one of the drawing tools (e.g. Pencil, Paintbrush or Airbrush) if you switch on Enable dynamics and set Dynamics to Color From Gradient. In the next step, set the gradients length and the Repeat style in the Fade Options section, and select a suitable gradient in the Color Options section. 3.2.6 – „Dynamics Options“ describes these parameters in more detail.
The following example shows the impact on the Pencil tool.
Different productions with the same gradient:
A few useful things to know about GIMP's gradients:
The first gradients in the list are special: They use the colors from the Foreground/Background Colors Area in the Toolbox, instead of being fixed.
FG to BG (HSV Counter-Clockwise) represents the hue succession in a color wheel from the selected hue to 360°.
FG to BG (HSV Clockwise) represents the hue succession in a color wheel from the selected hue to 0°.
FG to BG (RGB) is the RGB representation of the gradient from the Foreground color to the Background color in Toolbox.
FG to BG (Hard Edge)
With FG to Transparent, the selected hue becomes more and more transparent. You can modify these colors by using the Color Selector. Thus, by altering the foreground and background colors, you can make these gradients transition smoothly between any two colors you want.
FG to Transparent (Hard Edge)
Přechody nemusí zahrnovat pouze změny v barvě, ale i změny v její průhlednosti. Některé přechody jsou zcela neprůhledné, jiné obsahují průsvitné nebo zcela průhledné části. Pokud vyplňujete nebo malujete přechodem, který není zcela neprůhledný, bude zpoza něj prosvítat stávající obsah vrstvy.
You can create new custom gradients, using the Gradient Editor. You cannot modify the gradients that are supplied with GIMP, but you can duplicate them or create new ones, and then edit those.
The gradients that are supplied with GIMP are stored in
a system gradients
folder. By default, gradients
that you create are stored in a folder called
gradients
in your personal GIMP
directory. Any gradient files (ending with the extension
.ggr
) found in one of these folders, will
automatically be loaded when you start GIMP. You can
add more
directories to the gradient search path, if you want to, in the
Gradients tab of the Data
Folders pages of the Preferences dialog.
GIMP can also load gradient files in SVG format, used
by many vector graphics programs. To make GIMP load an
SVG gradient file, all you need to do is place it in the
gradients
folder of your personal
GIMP directory, or any other folder in your gradient
search path.
Tip | |
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Velké množství zajímavých SVG přechodů najdete na webu, zejména na stránce OpenClipArt [OPENCLIPART-GRADIENT] (anglicky). Pokud váš webový prohlížeč nepodporuje SVG, můžete si přechody prohlédnout až po jejich stáhnutí. |