An effect that shifts each pixel by a distance specified by
the first two bands of of the specified FloatMap
.
For each pixel in the output, the corresponding data from the
mapData
is retrieved, scaled and offset by the scale
and offset
attributes, scaled again by the size of the
source input image and used as an offset from the destination pixel
to retrieve the pixel data from the source input.
dst[x,y] = src[(x,y) + (offset+scale*map[x,y])*(srcw,srch)]A value of
(0.0, 0.0)
would specify no offset for the
pixel data whereas a value of (0.5, 0.5)
would specify
an offset of half of the source image size.
Note that the mapping is the offset from a destination pixel to
the source pixel location from which it is sampled which means that
filling the map with all values of 0.5
would displace the
image by half of its size towards the upper left since each destination
pixel would contain the data that comes from the source pixel below and
to the right of it.
Also note that this effect does not adjust the coordinates of input
events or any methods that measure containment on a Node
.
The results of mouse picking and the containment methods are undefined
when a Node
has a DisplacementMap
effect in place.
Example:
int width = 220;
int height = 100;
FloatMap floatMap = new FloatMap();
floatMap.setWidth(width);
floatMap.setHeight(height);
for (int i = 0; i < width; i++) {
double v = (Math.sin(i / 20.0 * Math.PI) - 0.5) / 40.0;
for (int j = 0; j < height; j++) {
floatMap.setSamples(i, j, 0.0f, (float) v);
}
DisplacementMap displacementMap = new DisplacementMap();
displacementMap.setMapData(floatMap);
Text text = new Text();
text.setX(40.0);
text.setY(80.0);
text.setText("Wavy Text");
text.setFill(Color.web("0x3b596d"));
text.setFont(Font.font(null, FontWeight.BOLD, 50));
text.setEffect(displacementMap);
}
The code above produces the following:
extends