/*
* GeoTools - The Open Source Java GIS Tookit
* http://geotools.org
*
* (C) 2006-2008, Open Source Geospatial Foundation (OSGeo)
*
* This file is hereby placed into the Public Domain. This means anyone is
* free to do whatever they wish with this file. Use it well and enjoy!
*/
package org.geotools.demo.coverage;
// J2SE and JAI dependencies
import java.awt.Color;
import java.awt.image.DataBuffer;
import java.awt.image.WritableRaster;
import javax.media.jai.RasterFactory;
import org.geotools.coverage.CoverageFactoryFinder;
import org.geotools.coverage.grid.GridCoverage2D;
import org.geotools.coverage.grid.GridCoverageFactory;
import org.geotools.geometry.Envelope2D;
import org.geotools.referencing.crs.DefaultGeographicCRS;
import org.opengis.coverage.grid.GridCoverage;
import org.opengis.geometry.Envelope;
import org.opengis.referencing.crs.CoordinateReferenceSystem;
/**
* A simple demo computing a {@linkplain WritableRaster raster} and displaying it. The raster uses
* {@code float} data type with arbitrary sample values. This demo consider the image as one and
* only one tile. Consequently, sample values are set directly in the raster (no need to deal for
* multi-tiles).
*
* @source $URL$
* @version $Id$
* @author Martin Desruisseaux
*/
public class FloatRasterDemo extends junit.framework.TestCase {
/**
* Run the demo.
*/
public static void main(String[] args) {
/*
* Set the pixel values. Because we use only one tile with one band, the code below
* is pretty similar to the code we would have if we were just setting the values in
* a matrix.
*/
final int width = 500;
final int height = 500;
WritableRaster raster = RasterFactory.createBandedRaster(DataBuffer.TYPE_FLOAT,
width, height, 1, null);
for (int y=0; y<height; y++) {
for (int x=0; x<width; x++) {
raster.setSample(x, y, 0, x+y);
}
}
/*
* Set some metadata (the CRS, the geographic envelope, etc.) and display the image.
* The display may be slow, since the translation from floating-point values to some
* color (or grayscale) is performed on the fly everytime the image is rendered.
*/
CoordinateReferenceSystem crs = DefaultGeographicCRS.WGS84;
Envelope envelope = new Envelope2D(crs, 0, 0, 30, 30);
GridCoverageFactory factory = CoverageFactoryFinder.getGridCoverageFactory(null);
GridCoverage gc = factory.create("My grayscale coverage", raster, envelope);
((GridCoverage2D) gc).show(); // Convenience method specific to Geotools.
/*
* The above example created a grayscale image. The example below creates a new grid
* coverage for the same data, but using a specified color map. Note that the factory
* used allows more details to be specified, for example units. Setting some of those
* arguments to null (as in this example) lets GridCoverage computes automatically a
* default value.
*/
Color[] colors = new Color[] {Color.BLUE, Color.CYAN, Color.WHITE, Color.YELLOW, Color.RED};
gc = factory.create("My colored coverage", raster, envelope,
null, null, null, new Color[][] {colors}, null);
((GridCoverage2D) gc).geophysics(false).show();
}
public void testCoverage() {
main(null);
}
}