/**
* Rectify elevation raster. For best performance each elevation raster must have correct
* parameters and values set. The <code>rectify()</code> operation validates that correct
* Elevation min and max values are set or calculated. All values that beyond min/max and voids,
* must be marked with "Missing Signal" (aka "nodata" value).
*
* @param raster A DataRaster to rectify
* @throws IllegalArgumentException if <code>raster</code> is <code>null</code>
*/
public static void rectify(ByteBufferRaster raster) throws IllegalArgumentException {
if (null == raster) {
String msg = Logging.getMessage("nullValue.RasterIsNull");
Logging.logger().finest(msg);
throw new IllegalArgumentException(msg);
}
int width = raster.getWidth();
int height = raster.getHeight();
if (width == 0 || height == 0) {
// nothing to do
return;
}
double[] minmax = raster.getExtremes();
if (null == minmax) {
// nothing to do
return;
}
Double minValue = minmax[0];
Double maxValue = minmax[1];
Double missingDataSignal = AVListImpl.getDoubleValue(raster, AVKey.MISSING_DATA_SIGNAL, null);
// check if the minimum value is one of the well known NODATA values
if (ElevationsUtil.isKnownMissingSignal(minValue)
|| (missingDataSignal != null && missingDataSignal.equals(minValue))) {
missingDataSignal = minValue;
raster.setTransparentValue(missingDataSignal);
minmax = raster.getExtremes();
if (null != minmax) {
minValue = minmax[0];
maxValue = minmax[1];
}
}
BufferWrapper bufferWrapper = raster.getBuffer();
// Allocate a buffer to hold one row of scalar values.
double[] array = new double[width];
boolean needsConversion = false;
double conversionValue = 1d;
if (raster.hasKey(AVKey.ELEVATION_UNIT)) {
String unit = raster.getStringValue(AVKey.ELEVATION_UNIT);
if (AVKey.UNIT_METER.equalsIgnoreCase(unit)) {
needsConversion = false;
} else if (AVKey.UNIT_FOOT.equalsIgnoreCase(unit)) {
needsConversion = true;
conversionValue = WWMath.convertFeetToMeters(1);
minValue = WWMath.convertFeetToMeters(minValue);
maxValue = WWMath.convertFeetToMeters(maxValue);
raster.setValue(AVKey.ELEVATION_UNIT, AVKey.UNIT_METER);
} else {
needsConversion = false;
String msg = Logging.getMessage("generic.UnrecognizedElevationUnit", unit);
Logging.logger().warning(msg);
}
}
boolean rasterHasVoids = false;
for (int j = 0; j < height; j++) {
bufferWrapper.getDouble(j * width, array, 0, width);
boolean commitChanges = false;
for (int i = 0; i < width; i++) {
double value = array[i];
if (null != missingDataSignal && value == missingDataSignal) {
rasterHasVoids = true;
} else {
if (needsConversion) {
value *= conversionValue;
commitChanges = true;
array[i] = value;
}
if (value < minValue || value > maxValue) {
rasterHasVoids = true;
if (null != missingDataSignal) {
array[i] = missingDataSignal;
commitChanges = true;
}
}
}
}
if (commitChanges) bufferWrapper.putDouble(j * width, array, 0, width);
}
if (rasterHasVoids) {
if (missingDataSignal != null) raster.setValue(AVKey.MISSING_DATA_SIGNAL, missingDataSignal);
} else {
raster.removeKey(AVKey.MISSING_DATA_SIGNAL);
}
raster.setValue(AVKey.ELEVATION_MIN, minValue);
raster.setValue(AVKey.ELEVATION_MAX, maxValue);
}
