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// Copyright (C) 1999-2018
// Smithsonian Astrophysical Observatory, Cambridge, MA, USA
// For conditions of distribution and use, see copyright notice in "copyright"
// This source has been modified from the original authored by
// Dr. Mark Calabretta as distributed with WCSLIBS under GNU GPL version 3
// WCSLIB 4.7 - an implementation of the FITS WCS standard.
// Copyright (C) 1995-2011, Mark Calabretta
#include <string.h>
#include <ctype.h>
#include <iostream>
#include <sstream>
#include <iomanip>
using namespace std;
#include "hpx.h"
#include "util.h"
#include "fitsy.h"
FitsHPX::FitsHPX(FitsFile* fits, Order oo, CoordSys ss, Layout ll,
int cc, int qq)
: order_(oo), coord_(ss), layout_(ll), quad_(qq)
{
FitsHead* head = fits->head();
FitsTableHDU* hdu = (FitsTableHDU*)(head->hdu());
col_ = (FitsBinColumn*)hdu->find(cc);
if (!col_)
return;
int nrow = hdu->rows();
int nelem = col_->repeat();
nside_ = head->getInteger("NSIDE",0);
long firstpix = head->getInteger("FIRSTPIX",-1);
long lastpix = head->getInteger("LASTPIX",-1);
if (!nside_) {
// Deduce NSIDE
if (lastpix >= 0) {
// If LASTPIX is present without NSIDE we can only assume it's npix.
nside_ = (int)(sqrt((double)((lastpix+1) / 12)) + 0.5);
}
else if (nrow)
nside_ = (int)(sqrt((double)((nrow * nelem) / 12)) + 0.5);
}
long npix = 12*nside_*nside_;
if (firstpix < 0)
firstpix = 0;
if (lastpix < 0)
lastpix = npix - 1;
build(fits);
if (byteswap_)
swap();
valid_ = 1;
}
FitsHPX::~FitsHPX()
{
if (data_)
delete [] (float*)data_;
}
void FitsHPX::build(FitsFile* fits)
{
// Number of facets on a side of each layout
const int NFACET[] = {5, 4, 4};
// Arrays that define the facet location and rotation for each recognised
// layout. Bear in mind that these appear to be upside-down, i.e. the top
// line contains facet numbers for the bottom row of the output image.
// Facets numbered -1 are blank.
// Equatorial (diagonal) facet layout.
const int FACETS[][5][5] = {{{ 6, 9, -1, -1, -1},
{ 1, 5, 8, -1, -1},
{-1, 0, 4, 11, -1},
{-1, -1, 3, 7, 10},
{-1, -1, -1, 2, 6}},
// North polar (X) facet layout.
{{ 8, 4, 4, 11, -1},
{ 5, 0, 3, 7, -1},
{ 5, 1, 2, 7, -1},
{ 9, 6, 6, 10, -1},
{-1, -1, -1, -1, -1}},
// South polar (X) facet layout.
{{ 1, 6, 6, 2, -1},
{ 5, 9, 10, 7, -1},
{ 5, 8, 11, 7, -1},
{ 0, 4, 4, 3, -1},
{-1, -1, -1, -1, -1}}};
// All facets of the equatorial layout are rotated by +45 degrees with
// respect to the normal orientation, i.e. that with the equator running
// horizontally. The rotation recorded for the polar facets is the number
// of additional positive (anti-clockwise) 90 degree turns with respect to
// the equatorial layout.
// Equatorial (diagonal), no facet rotation.
const int FROTAT[][5][5] = {{{ 0, 0, 0, 0, 0},
{ 0, 0, 0, 0, 0},
{ 0, 0, 0, 0, 0},
{ 0, 0, 0, 0, 0},
{ 0, 0, 0, 0, 0}},
// North polar (X) facet rotation.
{{ 3, 3, 0, 0, 0},
{ 3, 3, 0, 0, 0},
{ 2, 2, 1, 1, 0},
{ 2, 2, 1, 1, 0},
{ 0, 0, 0, 0, 0}},
// South polar (X) facet rotation.
{{ 1, 1, 2, 2, 0},
{ 1, 1, 2, 2, 0},
{ 0, 0, 3, 3, 0},
{ 0, 0, 3, 3, 0},
{ 0, 0, 0, 0, 0}}};
// Facet halving codes. 0: the facet is whole (or wholly blank),
// 1: blanked bottom-right, 2: top-right, 3: top-left, 4: bottom-left.
// Positive values mean that the diagonal is included, otherwise not.
// Equatorial (diagonal), no facet halving.
const int FHALVE[][5][5] = {{{ 0, 0, 0, 0, 0},
{ 0, 0, 0, 0, 0},
{ 0, 0, 0, 0, 0},
{ 0, 0, 0, 0, 0},
{ 0, 0, 0, 0, 0}},
// North polar (X) facet halving.
{{ 0, 1, -4, 0, 0},
{-3, 0, 0, 2, 0},
{ 4, 0, 0, -1, 0},
{ 0, -2, 3, 0, 0},
{ 0, 0, 0, 0, 0}},
// South polar (X) facet halving.
{{ 0, 1, -4, 0, 0},
{-3, 0, 0, 2, 0},
{ 4, 0, 0, -1, 0},
{ 0, -2, 3, 0, 0},
{ 0, 0, 0, 0, 0}}};
FitsHead* head = fits->head();
FitsTableHDU* hdu = (FitsTableHDU*)(head->hdu());
int rowlen = hdu->width();
int nrow = hdu->rows();
int repeat = col_->repeat();
char* data = (char*)fits->data();
int nside = nside_;
int layout = layout_;
int nfacet = NFACET[layout];
pWidth_ = nfacet*nside;
pHeight_ = pWidth_;
// create image space
size_t pSize = (size_t)pWidth_*pHeight_;
float* dest = new float[pSize];
for (longlong ii=0; ii<pSize; ii++)
dest[ii] = NAN;
// Write WCS keyrecords
initHeader(fits);
// Allocate arrays
long healidx[nside];
float row[nside];
// Loop vertically facet-by-facet.
longlong fpixel = 1;
// longlong group = 0;
longlong nelem = (longlong)nside;
for (int jfacet = 0; jfacet<nfacet; jfacet++) {
// Loop row-by-row.
for (int jj = 0; jj<nside; jj++) {
// Loop horizontally facet-by-facet
for (int ifacet = 0; ifacet<nfacet; ifacet++) {
int facet = FACETS[layout][jfacet][ifacet];
int rotn = FROTAT[layout][jfacet][ifacet];
int halve = FHALVE[layout][jfacet][ifacet];
// Recentre longitude?
if (quad_ && facet >= 0) {
if (facet <= 3) {
facet += quad_;
if (facet > 3) facet -= 4;
}
else if (facet <= 7) {
facet += quad_;
if (facet > 7) facet -= 4;
}
else {
facet += quad_;
if (facet > 11) facet -= 4;
}
}
// Write out the data
if (facet < 0)
;
else {
switch (order_) {
case NESTED:
NESTidx(nside, facet, rotn, jj, healidx);
break;
case RING:
RINGidx(nside, facet, rotn, jj, healidx);
break;
}
// Gather data into the output vector.
/*
long* healp = healidx;
for (float* rowp = row; rowp < row+nside; rowp++)
*rowp = col_->value(data+*(healp++),0);
*/
for (int ii=0; ii<nside_; ii++) {
int aa = healidx[ii]/repeat;
int bb = healidx[ii] - (aa*repeat);
if (aa<nrow)
row[ii] = col_->value(data+aa*rowlen,bb);
else
row[ii] = 0;
}
// Apply blanking to halved facets.
if (halve) {
int i1;
int i2;
if (abs(halve) == 1) {
// Blank bottom-right.
i1 = jj;
i2 = nside;
if (halve > 0)
i1++;
} else if (abs(halve) == 2) {
// Blank top-right.
i1 = nside - jj;
i2 = nside;
if (halve < 0)
i1--;
} else if (abs(halve) == 3) {
// Blank top-left.
i1 = 0;
i2 = jj;
if (halve < 0)
i2++;
} else {
// Blank bottom-left.
i1 = 0;
i2 = nside - jj;
if (halve > 0)
i2--;
}
for (float* rowp = row+i1; rowp < row+i2; rowp++)
*rowp = NAN;
}
// Write out this facet's contribution to this row of the map.
memcpy(dest+fpixel-1, row, nside*sizeof(float));
}
fpixel += nelem;
}
}
}
data_ = dest;
dataSize_ = pSize;
dataSkip_ = 0;
}
// (imap,jmap) are 0-relative pixel coordinates in the output map with origin
// at the bottom-left corner of the specified facet which is rotated by
// (45 + rotn * 90) degrees from its natural orientation; imap increases to
// the right and jmap upwards.
void FitsHPX::NESTidx(int nside, int facet, int rotn, int jmap, long *healidx)
{
// Nested index (0-relative) of the first pixel in this facet.
int hh = facet*nside*nside;
int nside1 = nside - 1;
long* hp = healidx;
for (int imap = 0; imap < nside; imap++, hp++) {
// (ii,jj) are 0-relative pixel coordinates with origin in the southern
// corner of the facet; i increases to the north-east and j to the
// north-west.
int ii =0;
int jj =0;
if (rotn == 0) {
ii = nside1 - imap;
jj = jmap;
}
else if (rotn == 1) {
ii = nside1 - jmap;
jj = nside1 - imap;
}
else if (rotn == 2) {
ii = imap;
jj = nside1 - jmap;
}
else if (rotn == 3) {
ii = jmap;
jj = imap;
}
*hp = 0;
int bit = 1;
while (ii || jj) {
if (ii & 1) *hp |= bit;
bit <<= 1;
if (jj & 1) *hp |= bit;
bit <<= 1;
ii >>= 1;
jj >>= 1;
}
*hp += hh;
}
}
// (imap,jmap) pixel coordinates are as described above for NESTidx(). This
// function computes the double-pixelisation index then converts it to the
// regular ring index.
void FitsHPX::RINGidx(int nside, int facet, int rotn, int jmap, long *healidx)
{
const int I0[] = { 1, 3, -3, -1, 0, 2, 4, -2, 1, 3, -3, -1};
const int J0[] = { 1, 1, 1, 1, 0, 0, 0, 0, -1, -1, -1, -1};
int n2side = 2 * nside;
int n8side = 8 * nside;
// Double-pixelisation index of the last pixel in the north polar cap. */
int npole = (n2side - 1) * (n2side - 1) - 1;
// Double-pixelisation pixel coordinates of the centre of the facet. */
int i0 = nside * I0[facet];
int j0 = nside * J0[facet];
int nside1 = nside - 1;
long* hp = healidx;
for (int imap = 0; imap < nside; imap++, hp++) {
// (ii,jj) are 0-relative, double-pixelisation pixel coordinates. The
// origin is at the intersection of the equator and prime meridian,
// i increases to the east (N.B.) and j to the north.
int ii =0;
int jj =0;
if (rotn == 0) {
ii = i0 + nside1 - (jmap + imap);
jj = j0 + jmap - imap;
}
else if (rotn == 1) {
ii = i0 + imap - jmap;
jj = j0 + nside1 - (imap + jmap);
}
else if (rotn == 2) {
ii = i0 + (imap + jmap) - nside1;
jj = j0 + imap - jmap;
}
else if (rotn == 3) {
ii = i0 + jmap - imap;
jj = j0 + jmap + imap - nside1;
}
// Convert i for counting pixels
if (ii < 0)
ii += n8side;
ii++;
if (jj > nside) {
// North polar regime.
if (jj == n2side)
*hp = 0;
else {
// Number of pixels in a polar facet with this value of jj.
int npj = 2 * (n2side - jj);
// Index of the last pixel in the row above this.
*hp = (npj - 1) * (npj - 1) - 1;
// Number of pixels in this row in the polar facets before this.
*hp += npj * (ii/n2side);
// Pixel number in this polar facet.
*hp += ii%n2side - (jj - nside) - 1;
}
}
else if (jj >= -nside) {
// Equatorial regime.
*hp = npole + n8side * (nside - jj) + ii;
}
else {
// South polar regime.
*hp = 24 * nside * nside + 1;
if (jj > -n2side) {
// Number of pixels in a polar facet with this value of jj.
int npj = 2 * (jj + n2side);
// Total number of pixels in this row or below it.
*hp -= (npj + 1) * (npj + 1);
// Number of pixels in this row in the polar facets before this.
*hp += npj * (ii/n2side);
// Pixel number in this polar facet.
*hp += ii%n2side + (nside + jj) - 1;
}
}
// Convert double-pixelisation index to regular.
*hp -= 1;
*hp /= 2;
}
}
void FitsHPX::initHeader(FitsFile* fits)
{
FitsHead* src = fits->head();
// create header
head_ = new FitsHead(pWidth_, pHeight_, 1, -32);
// OBJECT
char* object = src->getString("OBJECT");
if (object)
head_->appendString("OBJECT", object, NULL);
// CRPIX1/2
float crpix1;
switch (layout_) {
case EQUATOR:
crpix1 = (5 * nside_ + 1) / 2.;
break;
case NORTH:
case SOUTH:
crpix1 = (4 * nside_ + 1) / 2.;
break;
}
float crpix2 = crpix1;
head_->appendReal("CRPIX1", crpix1, 8, "Coordinate reference pixel");
head_->appendReal("CRPIX2", crpix2, 8, "Coordinate reference pixel");
// PCx_y
float cos45 = sqrt(2.0) / 2.0;
if (layout_ == EQUATOR) {
head_->appendReal("PC1_1", cos45, 8, "Transformation matrix element");
head_->appendReal("PC1_2", cos45, 8, "Transformation matrix element");
head_->appendReal("PC2_1", -cos45, 8, "Transformation matrix element");
head_->appendReal("PC2_2", cos45, 8, "Transformation matrix element");
}
// CDELT1/2
float cdelt1 = -90.0 / nside_ / sqrt(2.);
float cdelt2 = -cdelt1;
head_->appendReal("CDELT1", cdelt1, 8, "[deg] Coordinate increment");
head_->appendReal("CDELT2", cdelt2, 8, "[deg] Coordinate increment");
// CTYPE1/2
const char* pcode;
switch (layout_) {
case EQUATOR:
pcode = "HPX";
break;
case NORTH:
case SOUTH:
pcode = "XPH";
break;
}
const char* ctype1;
const char* ctype2;
const char* descr1;
const char* descr2;
switch (coord_) {
case EQU:
ctype1 = "RA--";
ctype2 = "DEC-";
descr1 = "Right ascension";
descr2 = "Declination";
break;
case GAL:
ctype1 = "GLON";
ctype2 = "GLAT";
descr1 = "Galactic longitude";
descr2 = "Galactic latitude";
break;
case ECL:
ctype1 = "ELON";
ctype2 = "ELAT";
descr1 = "Ecliptic longitude";
descr2 = "Ecliptic latitude";
break;
case UNKNOWN:
ctype1 = "XLON";
ctype2 = "XLAT";
descr1 = "Longitude";
descr2 = " Latitude";
}
{
ostringstream cval;
cval << ctype1 << '-' << pcode << ends;
ostringstream comm;
comm << descr1 << " in an " << pcode << " projection" << ends;
head_->appendString("CTYPE1", cval.str().c_str(), comm.str().c_str());
}
{
ostringstream cval;
cval << ctype2 << '-' << pcode << ends;
ostringstream comm;
comm << descr2 << " in an " << pcode << " projection" << ends;
head_->appendString("CTYPE2", cval.str().c_str(), comm.str().c_str());
}
// CRVAL1/CRVAL2
float crval1 = 0. + 90.*quad_;
float crval2;
switch (layout_) {
case EQUATOR:
crval2 = 0.;
break;
case NORTH:
crval1 += 180.;
crval2 = 90.;
break;
case SOUTH:
crval1 += 180.;
crval2 = -90.;
break;
}
if (360. < crval1)
crval1 -= 360.;
{
ostringstream comm;
comm << "[deg] " << descr1 << " at the reference point" << ends;
head_->appendReal("CRVAL1", crval1, 8, comm.str().c_str());
}
{
ostringstream comm;
comm << "[deg] " << descr2 << " at the reference point" << ends;
head_->appendReal("CRVAL2", crval2, 8, comm.str().c_str());
}
// PV2_1/2
switch (layout_) {
case EQUATOR:
head_->appendInteger("PV2_1", 4, "HPX H parameter (longitude)");
head_->appendInteger("PV2_2", 3, "HPX K parameter (latitude)");
break;
case NORTH:
case SOUTH:
head_->appendReal("LONPOLE", 180., 8, "[deg] Native longitude of the celestial pole");
break;
}
// we added cards
head_->updateHDU();
}
void FitsHPX::swap()
{
if (!data_)
return;
// we now need to byteswap back to native form
float* dest = (float*)data_;
for (int ii=0; ii<dataSize_; ii++) {
const char* p = (char*)(dest+ii);
union {
char c[4];
float f;
} u;
u.c[3] = *p++;
u.c[2] = *p++;
u.c[1] = *p++;
u.c[0] = *p;
dest[ii] = u.f;
}
}
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