// RA,Dec in degrees to Pixels.
anbool tpv_radec2pixelxy(const tpv_t* tpv, double ra, double dec, double *px, double *py) {
double x,y;
if (!tan_radec2pixelxy(&(tpv->wcstan), ra, dec, &x, &y))
return FALSE;
tpv_pixel_undistortion(tpv, x, y, px, py);
return TRUE;
}
static void set_grid(int GX, int GY, tan_t* tan, sip_t* sip,
double* tanxy, double* radec, double* xy,
double* gridx, double* gridy) {
int i, j;
if (GX == 1)
gridx[0] = 0.5 + 0.5 * tan->imagew;
else
for (i=0; i<GX; i++)
gridx[i] = 0.5 + i * tan->imagew / (GX-1);
if (GY == 1)
gridy[0] = 0.5 + 0.5 * tan->imageh;
else
for (i=0; i<GY; i++)
gridy[i] = 0.5 + i * tan->imageh / (GY-1);
for (i=0; i<GY; i++)
for (j=0; j<GX; j++) {
double ra, dec, x, y;
// Lay down the grid in (measured, distorted) CCD space
x = xy[2*(i*GX+j) + 0] = gridx[j];
y = xy[2*(i*GX+j) + 1] = gridy[i];
sip_pixelxy2radec(sip, x, y, &ra, &dec);
if(!tan_radec2pixelxy(tan, ra, dec, &x, &y)) perror("tan_radec2pixelxy==FALSE");
tanxy[2*(i*GX+j) + 0] = x;
tanxy[2*(i*GX+j) + 1] = y;
radec[2*(i*GX+j) + 0] = ra;
radec[2*(i*GX+j) + 1] = dec;
}
}
// RA,Dec in degrees to Pixels.
anbool sip_radec2pixelxy(const sip_t* sip, double ra, double dec, double *px, double *py) {
double x,y;
if (!tan_radec2pixelxy(&(sip->wcstan), ra, dec, &x, &y))
return FALSE;
sip_pixel_undistortion(sip, x, y, px, py);
return TRUE;
}
// RA,Dec in degrees to Pixels.
anbool sip_radec2pixelxy_check(const sip_t* sip, double ra, double dec, double *px, double *py) {
double u, v;
double U, V;
double U2, V2;
if (!tan_radec2pixelxy(&(sip->wcstan), ra, dec, px, py))
return FALSE;
if (!has_distortions(sip))
return TRUE;
// Subtract crpix, invert SIP distortion, add crpix.
// Sanity check:
if (sip->a_order != 0 && sip->ap_order == 0) {
fprintf(stderr, "suspicious inversion; no inversion SIP coeffs "
"yet there are forward SIP coeffs\n");
}
U = *px - sip->wcstan.crpix[0];
V = *py - sip->wcstan.crpix[1];
sip_calc_inv_distortion(sip, U, V, &u, &v);
// Check that we're dealing with the right range of the polynomial by inverting it and
// checking that we end up back in the right place.
sip_calc_distortion(sip, u, v, &U2, &V2);
if (fabs(U2 - U) + fabs(V2 - V) > 10.0)
return FALSE;
*px = u + sip->wcstan.crpix[0];
*py = v + sip->wcstan.crpix[1];
return TRUE;
}
void test_wcslib_equals_tan(CuTest* tc) {
#ifndef WCSLIB_EXISTS
printf("\n\nWarning, WCSLIB support was not compiled in, so no WCSLIB functionality will be tested.\n\n\n");
return;
#endif
anwcs_t* anwcs = NULL;
tan_t* tan;
char* tmpfile = create_temp_file("test-anwcs-wcs", "/tmp");
double x, y, x2, y2, ra, dec, ra2, dec2;
int ok, ok2;
int i;
// from http://live.astrometry.net/status.php?job=alpha-201004-29242410
// test-anwcs-1.wcs
const char* wcsliteral =
"SIMPLE = T / Standard FITS file BITPIX = 8 / ASCII or bytes array NAXIS = 0 / Minimal header EXTEND = T / There may be FITS ext CTYPE1 = 'RA---TAN' / TAN (gnomic) projection CTYPE2 = 'DEC--TAN' / TAN (gnomic) projection WCSAXES = 2 / no comment EQUINOX = 2000.0 / Equatorial coordinates definition (yr) LONPOLE = 180.0 / no comment LATPOLE = 0.0 / no comment CRVAL1 = 83.7131676182 / RA of reference point CRVAL2 = -5.10104333945 / DEC of reference point CRPIX1 = 221.593284607 / X reference pixel CRPIX2 = 169.655508041 / Y reference pixel CUNIT1 = 'deg ' / X pixel scale units CUNIT2 = 'deg ' / Y pixel scale units CD1_1 = 1.55258090814E-06 / Transformation matrix CD1_2 = 0.00081692280013 / no comment CD2_1 = -0.00081692280013 / no comment CD2_2 = 1.55258090814E-06 / no comment IMAGEW = 900 / Image width, in pixels. IMAGEH = 600 / Image height, in pixels. DATE = '2010-04-14T12:12:18' / Date this file was created. HISTORY Created by the Astrometry.net suite. HISTORY For more details, see http://astrometry.net . HISTORY Subversion URL HISTORY http://astrometry.net/svn/branches/astrometry/alpha/quads/ HISTORY Subversion revision 5409 HISTORY Subversion date 2007-10-09 13:49:13 -0400 (Tue, 09 Oct HISTORY 2007) HISTORY This WCS header was created by the program \"blind\". COMMENT -- blind solver parameters: -- COMMENT Index(0): /data1/INDEXES/200/index-219 COMMENT Index(1): /data1/INDEXES/200/index-218 COMMENT Index(2): /data1/INDEXES/200/index-217 COMMENT Index(3): /data1/INDEXES/200/index-216 COMMENT Index(4): /data1/INDEXES/200/index-215 COMMENT Index(5): /data1/INDEXES/200/index-214 COMMENT Index(6): /data1/INDEXES/200/index-213 COMMENT Index(7): /data1/INDEXES/200/index-212 COMMENT Index(8): /data1/INDEXES/200/index-211 COMMENT Index(9): /data1/INDEXES/200/index-210 COMMENT Index(10): /data1/INDEXES/200/index-209 COMMENT Index(11): /data1/INDEXES/200/index-208 COMMENT Index(12): /data1/INDEXES/200/index-207 COMMENT Index(13): /data1/INDEXES/200/index-206 COMMENT Index(14): /data1/INDEXES/200/index-205 COMMENT Index(15): /data1/INDEXES/200/index-204-00 COMMENT Index(16): /data1/INDEXES/200/index-204-01 COMMENT Index(17): /data1/INDEXES/200/index-204-02 COMMENT Index(18): /data1/INDEXES/200/index-204-03 COMMENT Index(19): /data1/INDEXES/200/index-204-04 COMMENT Index(20): /data1/INDEXES/200/index-204-05 COMMENT Index(21): /data1/INDEXES/200/index-204-06 COMMENT Index(22): /data1/INDEXES/200/index-204-07 COMMENT Index(23): /data1/INDEXES/200/index-204-08 COMMENT Index(24): /data1/INDEXES/200/index-204-09 COMMENT Index(25): /data1/INDEXES/200/index-204-10 COMMENT Index(26): /data1/INDEXES/200/index-204-11 COMMENT Index(27): /data1/INDEXES/200/index-203-00 COMMENT Index(28): /data1/INDEXES/200/index-203-01 COMMENT Index(29): /data1/INDEXES/200/index-203-02 COMMENT Index(30): /data1/INDEXES/200/index-203-03 COMMENT Index(31): /data1/INDEXES/200/index-203-04 COMMENT Index(32): /data1/INDEXES/200/index-203-05 COMMENT Index(33): /data1/INDEXES/200/index-203-06 COMMENT Index(34): /data1/INDEXES/200/index-203-07 COMMENT Index(35): /data1/INDEXES/200/index-203-08 COMMENT Index(36): /data1/INDEXES/200/index-203-09 COMMENT Index(37): /data1/INDEXES/200/index-203-10 COMMENT Index(38): /data1/INDEXES/200/index-203-11 COMMENT Index(39): /data1/INDEXES/200/index-202-00 COMMENT Index(40): /data1/INDEXES/200/index-202-01 COMMENT Index(41): /data1/INDEXES/200/index-202-02 COMMENT Index(42): /data1/INDEXES/200/index-202-03 COMMENT Index(43): /data1/INDEXES/200/index-202-04 COMMENT Index(44): /data1/INDEXES/200/index-202-05 COMMENT Index(45): /data1/INDEXES/200/index-202-06 COMMENT Index(46): /data1/INDEXES/200/index-202-07 COMMENT Index(47): /data1/INDEXES/200/index-202-08 COMMENT Index(48): /data1/INDEXES/200/index-202-09 COMMENT Index(49): /data1/INDEXES/200/index-202-10 COMMENT Index(50): /data1/INDEXES/200/index-202-11 COMMENT Index(51): /data1/INDEXES/200/index-201-00 COMMENT Index(52): /data1/INDEXES/200/index-201-01 COMMENT Index(53): /data1/INDEXES/200/index-201-02 COMMENT Index(54): /data1/INDEXES/200/index-201-03 COMMENT Index(55): /data1/INDEXES/200/index-201-04 COMMENT Index(56): /data1/INDEXES/200/index-201-05 COMMENT Index(57): /data1/INDEXES/200/index-201-06 COMMENT Index(58): /data1/INDEXES/200/index-201-07 COMMENT Index(59): /data1/INDEXES/200/index-201-08 COMMENT Index(60): /data1/INDEXES/200/index-201-09 COMMENT Index(61): /data1/INDEXES/200/index-201-10 COMMENT Index(62): /data1/INDEXES/200/index-201-11 COMMENT Index(63): /data1/INDEXES/200/index-200-00 COMMENT Index(64): /data1/INDEXES/200/index-200-01 COMMENT Index(65): /data1/INDEXES/200/index-200-02 COMMENT Index(66): /data1/INDEXES/200/index-200-03 COMMENT Index(67): /data1/INDEXES/200/index-200-04 COMMENT Index(68): /data1/INDEXES/200/index-200-05 COMMENT Index(69): /data1/INDEXES/200/index-200-06 COMMENT Index(70): /data1/INDEXES/200/index-200-07 COMMENT Index(71): /data1/INDEXES/200/index-200-08 COMMENT Index(72): /data1/INDEXES/200/index-200-09 COMMENT Index(73): /data1/INDEXES/200/index-200-10 COMMENT Index(74): /data1/INDEXES/200/index-200-11 COMMENT Field name: field.xy.fits COMMENT Field scale lower: 0.4 arcsec/pixel COMMENT Field scale upper: 720 arcsec/pixel COMMENT X col name: X COMMENT Y col name: Y COMMENT Start obj: 0 COMMENT End obj: 200 COMMENT Solved_in: solved COMMENT Solved_out: solved COMMENT Solvedserver: (null) COMMENT Parity: 2 COMMENT Codetol: 0.01 COMMENT Verify distance: 0 arcsec COMMENT Verify pixels: 1 pix COMMENT Maxquads: 0 COMMENT Maxmatches: 0 COMMENT Cpu limit: 0 s COMMENT Time limit: 0 s COMMENT Total time limit: 0 s COMMENT Total CPU limit: 600 s COMMENT Tweak: no COMMENT -- COMMENT -- properties of the matching quad: -- COMMENT quadno: 686636 COMMENT stars: 1095617,1095660,1095623,1095618 COMMENT field: 6,5,24,35 COMMENT code error: 0.00868071 COMMENT noverlap: 42 COMMENT nconflict: 1 COMMENT nfield: 88 COMMENT nindex: 139 COMMENT scale: 2.94093 arcsec/pix COMMENT parity: 1 COMMENT quads tried: 2166080 COMMENT quads matched: 2079562 COMMENT quads verified: 1747182 COMMENT objs tried: 0 COMMENT cpu time: 117.82 COMMENT -- AN_JOBID= 'alpha-201004-29242410' / Astrometry.net job ID END ";
if (write_file(tmpfile, wcsliteral, strlen(wcsliteral))) {
ERROR("Failed to write WCS to temp file %s", tmpfile);
CuFail(tc, "failed to write WCS to temp file");
}
tan = tan_read_header_file(tmpfile, NULL);
CuAssertPtrNotNull(tc, tan);
for (i=0; i<2; i++) {
if (i == 0) {
anwcs = anwcs_open_wcslib(tmpfile, 0);
} else if (i == 1) {
anwcs = anwcs_open_sip(tmpfile, 0);
}
CuAssertPtrNotNull(tc, anwcs);
/*
printf("ANWCS:\n");
anwcs_print(anwcs, stdout);
printf("TAN:\n");
tan_print_to(tan, stdout);
*/
/* this wcs has:
crval=(83.7132, -5.10104)
crpix=(221.593, 169.656)
CD = ( 1.5526e-06 0.00081692 )
( -0.00081692 1.5526e-06 )
*/
// check crval <-> crpix.
x = tan->crpix[0];
y = tan->crpix[1];
ra = 1; ra2 = 2; dec = 3; dec2 = 4;
tan_pixelxy2radec(tan, x, y, &ra, &dec);
CuAssertDblEquals(tc, tan->crval[0], ra, 1e-6);
CuAssertDblEquals(tc, tan->crval[1], dec, 1e-6);
ok = anwcs_pixelxy2radec(anwcs, x, y, &ra2, &dec2);
CuAssertIntEquals(tc, 0, ok);
CuAssertDblEquals(tc, tan->crval[0], ra2, 1e-6);
CuAssertDblEquals(tc, tan->crval[1], dec2, 1e-6);
ra = tan->crval[0];
dec = tan->crval[1];
x = 1; x2 = 2; y = 3; y2 = 4;
ok = tan_radec2pixelxy(tan, ra, dec, &x, &y);
CuAssertIntEquals(tc, TRUE, ok);
CuAssertDblEquals(tc, tan->crpix[0], x, 1e-6);
CuAssertDblEquals(tc, tan->crpix[1], y, 1e-6);
ok2 = anwcs_radec2pixelxy(anwcs, ra, dec, &x2, &y2);
CuAssertIntEquals(tc, 0, ok2);
CuAssertDblEquals(tc, tan->crpix[0], x2, 1e-6);
CuAssertDblEquals(tc, tan->crpix[1], y2, 1e-6);
// check pixel (0,0).
x = y = 0.0;
ra = 1; ra2 = 2; dec = 3; dec2 = 4;
tan_pixelxy2radec(tan, x, y, &ra, &dec);
ok = anwcs_pixelxy2radec(anwcs, x, y, &ra2, &dec2);
CuAssertIntEquals(tc, 0, ok);
CuAssertDblEquals(tc, ra, ra2, 1e-6);
CuAssertDblEquals(tc, dec, dec2, 1e-6);
// check RA,Dec (85, -4)
ra = 85;
dec = -4;
x = 1; x2 = 2; y = 3; y2 = 4;
ok = tan_radec2pixelxy(tan, ra, dec, &x, &y);
CuAssertIntEquals(tc, TRUE, ok);
ok2 = anwcs_radec2pixelxy(anwcs, ra, dec, &x2, &y2);
CuAssertIntEquals(tc, 0, ok2);
printf("x,y (%g,%g) vs (%g,%g)\n", x, y, x2, y2);
CuAssertDblEquals(tc, x, x2, 1e-6);
CuAssertDblEquals(tc, y, y2, 1e-6);
anwcs_free(anwcs);
}
free(tan);
}