This filter displaces pixels of active layer or selection according to
the grey levels of a Displacement map. Pixels are
displaced according to the gradient slope in the displacement map.
Pixels corresponding to solid areas are not displaced; the higher the
slope, the higher the displacement.
From left to right: original image, displace map, displaced image
With a non-linear gradient
With a complex gradient:
This filter offers the possibility of masking a part of the image to
protect it against filter action.
Activate the filter
This filter is found in the image window menu under
→ → .
This filter has no Preview.
Warp filter options
“Step” is displacement distance for every filter
iteration. A 10 value is necessary to get a one pixel
displacement. This value can be negative to invert
Iteration is the number of repetitions of
effect when applying filter.
Because of displacement, a part of pixels are driven over the
borders of layer or selection, and, on the opposite side, pixels
places are emptying. Four following options allow you to fix this
(default): What goes out on one side is going into the
Emptying places are filled with a spreading of the
neighbouring image line.
: Emptying places are filled with black color.
: Emptying places are filled with the Foreground color of the
color area in Toolbox.
To be listed in this drop-down list, the displacement map,
which is a grey-scaled image, must be present on
your screen when you call filter and must have the same size
as the original image.
Once all pixels displaced, this option scatters them randomly,
giving grain to the image. The higher this value (0.00-100.00),
the thinner the grain.
With a 3.00 dither size:
This option sets displacement angle of pixels according to the
slope direction of gradient. Previous examples have been created
with a vertical gradient and a 90° angle: so, pixels were
displaced horizontally and nothing went out of the image borders.
Here is an example with a 10° angle and 6 iterations:
With a 10° angle and 6 iterations:
In addition to displacement map, you can add a
Magnitude Map. This map is also a
grey-scaled image, with the same size as the source image and
which must be present on your screen when you call filter.
This map gives more or less strength to filter on some parts
of the image, according to the grey levels of this magnitude
map. Image areas corresponding to white parts of this map will
undergo all the strength of filter. Image areas corresponding
to black parts of the map will be spared by filter.
Intermediate grey levels will lessen filter action on
corresponding areas of the image. Use magnitude
map must be checked for that.
Magnitude Map example:
More Advanced Options
These extra options let you add two new maps, a gradient map and/or
a vector map.
To test these options alone, you must use a map with a solid color
for all the other maps.
The Gradient Map
The gradient map is also a grayscaled map.
Here, the displacement of pixels depends on the direction of
grayscale transitions. The Gradient scale
option lets you set how much the grayscale variations will
influence the displacement of pixels.
On every iteration, the filter works of the whole image, not
only on the red object: this explains burredness.
Gradient map example
The Vector Map
Vector map example
With this map, the displacement depends on the angle you set
in the Angle text box. 0° is upwards.
Angles go counter-clockwise. The Vector Magnitude
determines by how many pixels the image will move on