//
// RECTnav.java
//
/*
This source file is part of the edu.wisc.ssec.mcidas package and is
Copyright (C) 1998 - 2017 by Tom Whittaker, Tommy Jasmin, Tom Rink,
Don Murray, James Kelly, Bill Hibbard, Dave Glowacki, Curtis Rueden
and others.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA
*/
package edu.wisc.ssec.mcidas;
/**
* Navigation class for Radar (RECT) type nav. This code was modified
* from the original FORTRAN code (nvxrect.dlm) on the McIDAS system. It
* only supports latitude/longitude to line/element transformations (LL)
* and vice/versa. Transform to 'XYZ' not implemented.
* @see
* McIDAS Programmer's Manual
*
* @author Don Murray
*/
public final class RECTnav extends AREAnav
{
int itype;
int iwest;
double xrow;
double xcol;
double zslat;
double zslon;
double zdlat;
double zdlon;
/**
* Set up for the real math work. Must pass in the int array
* of the RECT nav 'codicil'.
*
* @param iparms the nav block from the image file
* @throws IllegalArgumentException
* if the nav block is not a RECT type.
*/
public RECTnav (int[] iparms)
throws IllegalArgumentException
{
/* No longer needed. Kept for consistency with nvxrect.dlm
if (ifunc != 1)
{
if (iparms[0] == XY ) itype = 1;
if (iparms[0] == LL ) itype = 2;
return;
}
*/
if (iparms[0] != RECT )
throw new IllegalArgumentException("Invalid navigation type" +
iparms[0]);
itype = 2;
xrow = iparms[1];
int ipowlat = iparms[11];
if (ipowlat == 0) ipowlat = 4;
zslat = iparms[2]/Math.pow(10.,ipowlat);
xcol = iparms[3];
int ipowlon = iparms[12];
if (ipowlon == 0) ipowlon = 4;
zslon = iparms[4]/Math.pow(10.,ipowlon);
int ipowdlin = iparms[13];
if (ipowdlin == 0) ipowdlin = 4;
zdlat = iparms[5]/Math.pow(10.,ipowdlin);
int ipowdele = iparms[14];
if (ipowdele == 0) ipowdele = 4;
zdlon = iparms[6]/Math.pow(10.,ipowdele);
int ipowrad = iparms[15];
if (ipowrad == 0) ipowrad = 3;
int ipowecc = iparms[16];
if (ipowecc == 0) ipowecc = 6;
iwest = (iparms[10] >= 0) ? 1 : -1;
if (xcol == 1) {
zslon=zslon-180.0*iwest;
}
}
/** converts from satellite coordinates to latitude/longitude
*
* @param linele array of line/element pairs. Where
* linele[indexLine][] is a 'line' and
* linele[indexEle][] is an element. These are in
* 'file' coordinates (not "image" coordinates.)
*
* @return latlon[][] array of lat/long pairs. Output array is
* latlon[indexLat][] of latitudes and
* latlon[indexLon][] of longitudes.
*
*/
public double[][] toLatLon(double[][] linele)
{
double xldif;
double xedif;
double xlon;
double xlat;
double xele;
double xlin;
int number = linele[0].length;
double[][] latlon = new double[2][number];
// Convert array to Image coordinates for computations
double[][] imglinele = areaCoordToImageCoord(linele);
for (int point=0; point < number; point++)
{
xlin = imglinele[indexLine][point];
xele = imglinele[indexEle][point];
xldif = xrow - xlin;
if (xcol == 1) {
xedif = iwest * (xele-xcol);
xlon = zslon + 180*iwest-xedif*zdlon;
} else {
xedif = iwest * (xcol-xele);
xlon = zslon + xedif*zdlon;
}
xlat = zslat + xldif*zdlat;
if (xlat > 90. || xlat < -90.)
{
xlat = Double.NaN;
}
if (xlon > (zslon+180) ||
xlon < (zslon-180)) {
xlon = Double.NaN;
}
if (!Double.isNaN(xlon)) {
if (xlon < -180.)
{
xlon = xlon + 360.;
//if (xlon < -180.) xlon = Double.NaN;
}
if (xlon > 180)
{
xlon = xlon - 360.;
//if (xlon > 180.) xlon = Double.NaN;
}
}
if (Double.isNaN(xlat) || Double.isNaN(xlon))
{
latlon[indexLat][point] = Double.NaN;
latlon[indexLon][point] = Double.NaN;
}
else
{
latlon[indexLat][point] = xlat;
latlon[indexLon][point] = (iwest == 1) ? -xlon : xlon;
}
} // end point for loop
return latlon;
}
/**
* toLinEle converts lat/long to satellite line/element
*
* @param latlon array of lat/long pairs. Where latlon[indexLat][]
* are latitudes and latlon[indexLon][] are longitudes.
*
* @return linele[][] array of line/element pairs. Where
* linele[indexLine][] is a line and linele[indexEle][]
* is an element. These are in 'file' coordinates
* (not "image" coordinates);
*/
public double[][] toLinEle(double[][] latlon)
{
double xlon;
double xlat;
double xlin;
double xele;
int number = latlon[0].length;
double[][] linele = new double[2][number];
for (int point=0; point < number; point++)
{
xlat = latlon[indexLat][point];
// transform to McIDAS (west positive longitude) coordinates
xlon = (iwest == 1)
? -latlon[indexLon][point]
: latlon[indexLon][point];
if (xlon > (zslon+180)) {
xlon = xlon-360;
} else if (xlon < zslon-180) {
xlon = xlon+360;
}
//if (iwest == -1 && xlon < zslon) xlon = xlon +360.;
xlin = xrow - (xlat - zslat)/zdlat;
if (xcol == 1) {
xele = xcol - (xlon - zslon-180*iwest)/(zdlon*iwest);
} else {
xele = xcol - (xlon - zslon)/(zdlon*iwest);
}
linele[indexLine][point] = xlin;
linele[indexEle][point] = xele;
} // end point loop
// Return in 'File' coordinates
return imageCoordToAreaCoord(linele, linele);
}
/** converts from satellite coordinates to latitude/longitude
*
* @param linele array of line/element pairs. Where
* linele[indexLine][] is a 'line' and
* linele[indexEle][] is an element. These are in
* 'file' coordinates (not "image" coordinates.)
*
* @return latlon[][] array of lat/long pairs. Output array is
* latlon[indexLat][] of latitudes and
* latlon[indexLon][] of longitudes.
*
*/
public float[][] toLatLon(float[][] linele)
{
double xldif;
double xedif;
double xlon;
double xlat;
double xele;
double xlin;
int number = linele[0].length;
float[][] latlon = new float[2][number];
// Convert array to Image coordinates for computations
float[][] imglinele = areaCoordToImageCoord(linele);
for (int point=0; point < number; point++)
{
xlin = imglinele[indexLine][point];
xele = imglinele[indexEle][point];
xldif = xrow - xlin;
if (xcol == 1) {
xedif = iwest * (xele-xcol);
xlon = zslon + 180*iwest-xedif*zdlon;
} else {
xedif = iwest * (xcol-xele);
xlon = zslon + xedif*zdlon;
}
xlat = zslat + xldif*zdlat;
if (xlat > 90. || xlat < -90.)
{
xlat = Double.NaN;
}
if (xlon > (zslon+180) ||
xlon < (zslon-180)) {
xlon = Double.NaN;
}
if (!Double.isNaN(xlon)) {
if (xlon < -180.)
{
xlon = xlon + 360.;
//if (xlon < -180.) xlon = Double.NaN;
}
if (xlon > 180)
{
xlon = xlon - 360.;
//if (xlon > 180.) xlon = Double.NaN;
}
}
if (Double.isNaN(xlat) || Double.isNaN(xlon))
{
latlon[indexLat][point] = Float.NaN;
latlon[indexLon][point] = Float.NaN;
}
else
{
latlon[indexLat][point] = (float) xlat;
latlon[indexLon][point] = (float) ((iwest == 1) ? -xlon : xlon);
}
} // end point for loop
return latlon;
}
/**
* toLinEle converts lat/long to satellite line/element
*
* @param latlon array of lat/long pairs. Where latlon[indexLat][]
* are latitudes and latlon[indexLon][] are longitudes.
*
* @return linele[][] array of line/element pairs. Where
* linele[indexLine][] is a line and linele[indexEle][]
* is an element. These are in 'file' coordinates
* (not "image" coordinates);
*/
public float[][] toLinEle(float[][] latlon)
{
double xlon;
double xlat;
double xlin;
double xele;
int number = latlon[0].length;
float[][] linele = new float[2][number];
for (int point=0; point < number; point++)
{
xlat = latlon[indexLat][point];
// transform to McIDAS (west positive longitude) coordinates
xlon = (iwest == 1)
? -latlon[indexLon][point]
: latlon[indexLon][point];
if (xlon > (zslon+180)) {
xlon = xlon-360;
} else if (xlon < zslon-180) {
xlon = xlon+360;
}
//if (iwest == -1 && xlon < zslon) xlon = xlon +360.;
xlin = xrow - (xlat - zslat)/zdlat;
if (xcol == 1) {
xele = xcol - (xlon - zslon-180*iwest)/(zdlon*iwest);
} else {
xele = xcol - (xlon - zslon)/(zdlon*iwest);
}
linele[indexLine][point] = (float) xlin;
linele[indexEle][point] = (float) xele;
} // end point loop
// Return in 'File' coordinates
return imageCoordToAreaCoord(linele, linele);
}
}
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