File: math.c

package info (click to toggle)
libpano13 2.9.19+dfsg-1
  • links: PTS, VCS
  • area: main
  • in suites: jessie, jessie-kfreebsd
  • size: 8,736 kB
  • ctags: 3,225
  • sloc: ansic: 34,695; sh: 11,214; makefile: 311; perl: 242
file content (2834 lines) | stat: -rw-r--r-- 77,591 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
/* Panorama_Tools       -       Generate, Edit and Convert Panoramic Images
   Copyright (C) 1998,1999 - Helmut Dersch  der@fh-furtwangen.de
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this software; see the file COPYING.  If not, a copy
   can be downloaded from http://www.gnu.org/licenses/gpl.html, or
   obtained by writing to the Free Software Foundation, Inc.,
   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */

/*------------------------------------------------------------*/


#include "filter.h"
#include <float.h>
#include "f2c.h"

#include "PaniniGeneral.h"

#define R_EPS  1.0e-6   
#define MAXITER 100

#include <assert.h>


#ifndef abs
#define abs(a) ( (a) >= 0 ? (a) : -(a) )
#endif

#ifdef _MSC_VER
#define isnan(a) _isnan(a)
#define isinf(a) (_fpclass(a) == _FPCLASS_NINF || _fpclass(a) == _FPCLASS_PINF)
#endif

void    matrix_matrix_mult      ( double m1[3][3],double m2[3][3],double result[3][3]);
int     polzeros_();

void cubeZero( double *a, int *n, double *root );
void squareZero( double *a, int *n, double *root );
double cubeRoot( double x );


//------------------------- Some auxilliary math functions --------------------------------------------

// atanh is not available on MSVC until Visual Studio 2012. Use the atanh routine from gsl.
#if defined _MSC_VER && _MSC_VER < 1700

#define GSL_DBL_EPSILON        2.2204460492503131e-16
#define GSL_SQRT_DBL_EPSILON   1.4901161193847656e-08 

static double
log1p (const double x)
{
  volatile double y;
  y = 1 + x;
  return log(y) - ((y-1)-x)/y ;  /* cancels errors with IEEE arithmetic */
} 

static double
atanh (const double x)
{
  double a = fabs (x);
  double s = (x < 0) ? -1 : 1;

  if (a > 1)
    {
      //return NAN;
      return 0;
    }
  else if (a == 1)
    {
      //return (x < 0) ? GSL_NEGINF : GSL_POSINF; 
      return (x < 0) ? -1e300 : 1e300;
    }
  else if (a >= 0.5)
    {
      return s * 0.5 * log1p (2 * a / (1 - a));
    }
  else if (a > GSL_DBL_EPSILON)
    {
      return s * 0.5 * log1p (2 * a + 2 * a * a / (1 - a));
    }
  else
    {
      return x;
    }
} 
#endif

void matrix_mult( double m[3][3], double vector[3] )
{
        register int i;
        register double v0 = vector[0];
        register double v1 = vector[1];
        register double v2 = vector[2];
        
        
        for(i=0; i<3; i++)
        {
                vector[i] = m[i][0] * v0 + m[i][1] * v1 + m[i][2] * v2;
        }
}
                
void matrix_inv_mult( double m[3][3], double vector[3] )
{
        register int i;
        register double v0 = vector[0];
        register double v1 = vector[1];
        register double v2 = vector[2];
        
        for(i=0; i<3; i++)
        {
                vector[i] = m[0][i] * v0 + m[1][i] * v1 + m[2][i] * v2;
        }
}
                
void matrix_matrix_mult( double m1[3][3],double m2[3][3],double result[3][3])
{
        register int i,k;
        
        for(i=0;i<3;i++)
        {
                for(k=0; k<3; k++)
                {
                        result[i][k] = m1[i][0] * m2[0][k] + m1[i][1] * m2[1][k] + m1[i][2] * m2[2][k];
                }
        }
}

// Set matrix elements based on Euler angles a, b, c

void SetMatrix( double a, double b, double c , double m[3][3], int cl )
{
        double mx[3][3], my[3][3], mz[3][3], dummy[3][3];
        

        // Calculate Matrices;

        mx[0][0] = 1.0 ;                                mx[0][1] = 0.0 ;                                mx[0][2] = 0.0;
        mx[1][0] = 0.0 ;                                mx[1][1] = cos(a) ;                     mx[1][2] = sin(a);
        mx[2][0] = 0.0 ;                                mx[2][1] =-mx[1][2] ;                   mx[2][2] = mx[1][1];
        
        my[0][0] = cos(b);                              my[0][1] = 0.0 ;                                my[0][2] =-sin(b);
        my[1][0] = 0.0 ;                                my[1][1] = 1.0 ;                                my[1][2] = 0.0;
        my[2][0] = -my[0][2];                   my[2][1] = 0.0 ;                                my[2][2] = my[0][0];
        
        mz[0][0] = cos(c) ;                     mz[0][1] = sin(c) ;                     mz[0][2] = 0.0;
        mz[1][0] =-mz[0][1] ;                   mz[1][1] = mz[0][0] ;                   mz[1][2] = 0.0;
        mz[2][0] = 0.0 ;                                mz[2][1] = 0.0 ;                                mz[2][2] = 1.0;

        if( cl )
                matrix_matrix_mult( mz, mx,     dummy);
        else
                matrix_matrix_mult( mx, mz,     dummy);
        matrix_matrix_mult( dummy, my, m);
}


// Do 3D-coordinate Transformation

void doCoordinateTransform( CoordInfo *ci, tMatrix *t )
{
        double m[3][3],a,b,c;
        int i;
        double mx[3][3], my[3][3], mz[3][3], dummy[3][3];
        

        // Calculate Matrices;
        a = DEG_TO_RAD( t->alpha );
        b = DEG_TO_RAD( t->beta  );
        c = DEG_TO_RAD( t->gamma );

        mx[0][0] = 1.0 ;                                mx[0][1] = 0.0 ;                                mx[0][2] = 0.0;
        mx[1][0] = 0.0 ;                                mx[1][1] = cos(a) ;                     mx[1][2] = sin(a);
        mx[2][0] = 0.0 ;                                mx[2][1] =-mx[1][2] ;                   mx[2][2] = mx[1][1];
        
        my[0][0] = cos(b);                              my[0][1] = 0.0 ;                                my[0][2] =-sin(b);
        my[1][0] = 0.0 ;                                my[1][1] = 1.0 ;                                my[1][2] = 0.0;
        my[2][0] = -my[0][2];                   my[2][1] = 0.0 ;                                my[2][2] = my[0][0];
        
        mz[0][0] = cos(c) ;                     mz[0][1] = sin(c) ;                     mz[0][2] = 0.0;
        mz[1][0] =-mz[0][1] ;                   mz[1][1] = mz[0][0] ;                   mz[1][2] = 0.0;
        mz[2][0] = 0.0 ;                                mz[2][1] = 0.0 ;                                mz[2][2] = 1.0;

        matrix_matrix_mult( my, mz,     dummy);
        matrix_matrix_mult( mx, dummy,  m);
        
        // Scale 
        
        for(i=0; i<3; i++)
                ci->x[i] *= t->scale;
        
        // Do shift
        
        for(i=0; i<3; i++)
                ci->x[i] += t->x_shift[i];
        
        // Do rotation
#if 0   
        SetMatrix( DEG_TO_RAD( t->alpha ) , 
                           DEG_TO_RAD( t->beta  ) ,
                           DEG_TO_RAD( t->gamma ) ,
                           m, 0 );

#endif
        matrix_inv_mult( m, ci->x );

}

void SettMatrixDefaults( tMatrix *t )
{
        int i;
        
        t->alpha = t->beta = t->gamma = 0.0;
        for(i=0; i<3; i++)
                t->x_shift[i] = 0.0;
        
        t->scale = 1.0;
}


        
        
        
        

//------------------------------- Transformation functions --------------------------------------------


#define         distanceparam   (*((double*)params))
#define         shift           (*((double*)params))
#define         var0            ((double*)params)[0]
#define         var1            ((double*)params)[1]
#define         var2            ((double*)params)[2]
#define         var3            ((double*)params)[3]
#define         mp              ((struct MakeParams*)params)

// execute a stack of functions stored in stack

void execute_stack              ( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
        register double                 xd = x_dest, 
                                                        yd = y_dest;
        register struct fDesc*  stack = (struct fDesc *) params;;
        
                
        while( (stack->func) != NULL )
        {

                (stack->func) ( xd, yd, x_src, y_src, stack->param );
                xd = *x_src;    
                yd = *y_src;
                stack++;
        }
}

        
int execute_stack_new( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
    register double xd = x_dest,
                    yd = y_dest;
    register struct fDesc*  stack = (struct fDesc *) params;

    while( (stack->func) != NULL )
    {
        if ( (stack->func) ( xd, yd, x_src, y_src, stack->param ) ) {
            //      printf("Execute stack %f %f %f %f\n", xd, yd, *x_src, *y_src);
            xd = *x_src;
            yd = *y_src;
            stack++;
        } else {
            return 0;
        }
    }
    return 1;
}


// Rotate equirectangular image

int rotate_erect( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
        // params: double 180degree_turn(screenpoints), double turn(screenpoints);

                *x_src = x_dest + var1;

                while( *x_src < - var0 )
                        *x_src += 2 *  var0;

                while( *x_src >  var0 )
                        *x_src -= 2 *  var0;

                *y_src = y_dest ;
    return 1;
}



// Calculate inverse 4th order polynomial correction using Newton
// Don't use on large image (slow)!


int inv_radial( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
        // params: double coefficients[4]

        register double rs, rd, f, scale;
        int iter = 0;

        rd              = (sqrt( x_dest*x_dest + y_dest*y_dest )) / ((double*)params)[4]; // Normalized 

        rs      = rd;                           
        f       = (((((double*)params)[3] * rs + ((double*)params)[2]) * rs + 
                                ((double*)params)[1]) * rs + ((double*)params)[0]) * rs;

        while( abs(f - rd) > R_EPS && iter++ < MAXITER )
        {
                rs = rs - (f - rd) / ((( 4 * ((double*)params)[3] * rs + 3 * ((double*)params)[2]) * rs  + 
                                                  2 * ((double*)params)[1]) * rs + ((double*)params)[0]);

                f       = (((((double*)params)[3] * rs + ((double*)params)[2]) * rs + 
                                ((double*)params)[1]) * rs + ((double*)params)[0]) * rs;
        }

        scale = (rd!=0.0) ? rs / rd : 1.0f;
//      printf("scale = %lg iter = %d\n", scale,iter);  
        
        *x_src = x_dest * scale  ;
        *y_src = y_dest * scale  ;
    return 1;
}

int inv_vertical( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
        // params: double coefficients[4]

        register double rs, rd, f, scale;
        int iter = 0;

        rd              = abs( y_dest ) / ((double*)params)[4]; // Normalized 

        rs      = rd;                           
        f       = (((((double*)params)[3] * rs + ((double*)params)[2]) * rs + 
                                ((double*)params)[1]) * rs + ((double*)params)[0]) * rs;

        while( abs(f - rd) > R_EPS && iter++ < MAXITER )
        {
                rs = rs - (f - rd) / ((( 4 * ((double*)params)[3] * rs + 3 * ((double*)params)[2]) * rs  + 
                                                  2 * ((double*)params)[1]) * rs + ((double*)params)[0]);

                f       = (((((double*)params)[3] * rs + ((double*)params)[2]) * rs + 
                                ((double*)params)[1]) * rs + ((double*)params)[0]) * rs;
        }

        scale = rs / rd;
//      printf("scale = %lg iter = %d\n", scale,iter);  
        
        *x_src = x_dest  ;
        *y_src = y_dest * scale  ;
    return 1;
}



int resize( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
        // params: double scale_horizontal, double scale_vertical;

                *x_src = x_dest * var0;
                *y_src = y_dest * var1;
    return 1;
}

int tiltInverse( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
        
  // 
  // This is really the inverse transformation
  
  //	printf( "Entered invtilt function \n");
  
  
    double theta = mp->tilt[0];            // use the tilt angle specified by the 'L' parameter
    double sigma = mp->tilt[1];            // use the tilt angle specified by the 'L' parameter
    double phi   = mp->tilt[2];
    double scale = mp->tilt[3];
    double v[3];                                            // 3D projective coordinate vector
    double m_tilt[3][3];                            // tilt matrix
    double m_rotate[3][3];                            // tilt matrix
    double xmax = mp->im->width/2;          // maximum y value is image width divided by 2
    double z0;
    double FOV = DEG_TO_RAD(mp->im->hfov/scale);                  
    double m_slant[3][3];                           // slant matrix
    
    //        printf("Tilt Inverse %5.2f %5.2f %5.2f, %5.2f\n", x_dest, y_dest, theta, sigma);
    
    // These operations are based on the typical projection of a point to a camera.
    // But, we want the projection to happen without translation, so we need to subtract
    // the coordinates of 0,0 projected... that is why the [1][2], [2][2] components
    // of the matrix are 0 or 1 in the tilt-x and tilt-y
    
    
    // Tilt (around X) INVERSE. The matrix does not require the [1][2], [2][2]
    // because it is tilted in its center
    m_tilt[0][0] = 1;       m_tilt[0][1] = 0;                               m_tilt[0][2] = 0;
    m_tilt[1][0] = 0;       m_tilt[1][1] = cos(theta);                      m_tilt[1][2] = 0; // sin(theta); 
    m_tilt[2][0] = 0;       m_tilt[2][1] = -sin(theta);                     m_tilt[2][2] = 1; //cos(theta);
    
    // Tilt (around Y) INVERSE.       
    // [0][2] and [2][2] are changed to tilt on center of image. See above
    m_slant[0][0] = cos(sigma);	m_slant[0][1] = 0;		m_slant[0][2] = 0; //-sin(sigma);
    m_slant[1][0] = 0;		m_slant[1][1] = 1;		m_slant[1][2] = 0;
    m_slant[2][0] = sin(sigma);	m_slant[2][1] = 0;		m_slant[2][2] = 1; //cos(sigma);
    
    // Slant (around z)
    
    // Tilt (around z) INVERSE 
    m_rotate[0][0] = cos(phi);	m_rotate[0][1] = sin(phi);		m_rotate[0][2] = 0;
    m_rotate[1][0] = -sin(phi);	m_rotate[1][1] = cos(phi);		m_rotate[1][2] = 0;
    m_rotate[2][0] = 0;	        m_rotate[2][1] = 0;		        m_rotate[2][2]=  1;
    
    z0 = xmax/tan(FOV/2);           // FOV is full angle FOV in radians
    //    printf("Values Forward %5.2f %5.2f %5.2f, %5.2f\n", x_dest, y_dest, distanceparam, z0);
    
    // z0 is distance to image from center of projection                                            
    
    //printf("z0 is %f \n", z0);
    // Now you have [x_dest, y_dest, z1]'.  Multiply that vector by M, the adjusted tilt matrix
    v[0] = x_dest;
    v[1] = y_dest;
    v[2] = z0;
    
    matrix_mult(m_rotate,v);
    matrix_mult(m_slant,v);
    matrix_mult(m_tilt,v);

    
    // Now project into xy plane
    *x_src =  v[0]* z0 /v[2];
    *y_src =  v[1]* z0 /v[2];

// THIS IS THE OPTIMIZED VERSION with no matrices multiplications. ..
#ifdef OPTIMIZED
    double x = x_dest;
    double y = y_dest;
    double above = (x * cos(phi) + y * sin(phi)) * cos (sigma);
    double below1  = (x * cos(phi) + y * sin(phi)) * sin(sigma);
    double below2 = - sin(theta) * (y * cos(phi) - x * sin(phi));
    double x4 = z0*  above / (below1 + below2 + z0);

    above  = (-x * sin (phi) + y * cos(phi)) * cos(theta);
    below1 = (x * cos(phi) + y * sin(phi)) * sin (sigma);
    below2 = (-x * sin(phi) + y * cos(phi)) * sin(theta);
    
    double y4 = z0 * above / (below1 - below2 + z0);
#endif

//    printf("x4 %6.2f x_c %6.2f\n", x4, *x_src);
//    printf("x4 %6.2f x_c %6.2f\n", y4, *y_src);

    
    return 1;
}

// Dev: inverse tilt function.  Substitute correct matrix for "un-tilting"
int tiltForward( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
  // INVERSE is a misnomer --panotools ##$&^
  // This is really the forward transformation

  //	printf( "Entered invtilt function \n");

	double phi = mp->tilt[0];		// use the tilt angle specified by the 'L' parameter (already in radians)
	double phi2 = mp->tilt[1];		// use the tilt angle specified by the 'L' parameter (already in radians)
        double phi3  = mp->tilt[2];
        double scale  = mp->tilt[3];

	double v[3];						// 3D projective coordinate vector
	double m_tilt[3][3];				// tilt matrix
	double xmax = mp->im->width/2;		// maximum y value is image width divided by 2
	double z0, z1, s;
	double FOV = DEG_TO_RAD(mp->im->hfov/scale);
        double m_slant[3][3];                           // slant matrix
        double m_rotate[3][3];                          // tilt matrix

//        printf("Tilt Forward %5.2f %5.2f angles %5.2f, %5.2f, %5.2f\n", x_dest, y_dest, phi, phi2, phi3);

	// TILT TO STRAIGHT matrix (tilt2() in MATLAB).  Really and UN-TILTING matrix
        // FORWARD
	m_tilt[0][0] = 1;	m_tilt[0][1] = 0;		m_tilt[0][2] = 0;
	m_tilt[1][0] = 0;	m_tilt[1][1] = 1/cos(phi);	m_tilt[1][2] = 0;
	m_tilt[2][0] = 0;	m_tilt[2][1] = tan(phi);	m_tilt[2][2] = 1;
								

	m_slant[0][0] = 1/cos(phi2);	m_slant[0][1] = 0;		m_slant[0][2] = 0;
	m_slant[1][0] = 0;		m_slant[1][1] = 1;		m_slant[1][2] = 0;
	m_slant[2][0] = -sin(phi2)/cos(phi2);	m_slant[2][1] = 0;		m_slant[2][2] = 1;

        // FORWARD
        m_rotate[0][0] = cos(phi3);	m_rotate[0][1] = -sin(phi3);		m_rotate[0][2] = 0;
        m_rotate[1][0] = sin(phi3);	m_rotate[1][1] = cos(phi3);		m_rotate[1][2] = 0;
        m_rotate[2][0] = 0;	        m_rotate[2][1] = 0;		        m_rotate[2][2]=  1;



	z0 = xmax/tan(FOV/2); 		// FOV is full angle FOV in radians
								// z0 is distance to image from center of projection						
        // First step, undo the projection of the point
        z1 = (z0 * z0) /(x_dest * (-sin(phi2)/cos(phi2))  + y_dest * tan(phi) + z0);
        
        s = z1 / z0;
        s = z0 /(x_dest * (-sin(phi2)/cos(phi2))  + y_dest * sin(phi)/cos(phi) + z0);
        z1 = (z0* z0) /(x_dest * (-sin(phi2)/cos(phi2))  + y_dest * sin(phi)/cos(phi) + z0);

        //(y_dest * tan(phi) + x_dest * tan(phi2) + z0);

	//s = z0 / (y_dest * tan(phi) + z0);		// s is a scaling factor ...
        
	//printf("z0 is %f \n", z0);
	// Now you have [x_dest, y_dest, z1]'.  Multiply that vector by M, the adjusted tilt matrix
	v[0] =  s* x_dest;
	v[1] =  s* y_dest;
	v[2] =  z1;

        //	matrix_mult(m_tilt,v);
        matrix_mult(m_tilt,v);
        matrix_mult(m_slant,v);
	matrix_mult(m_rotate,v);

	*x_src =   v[0] ;			// convert back to cartesian coordinates
	*y_src =   v[1];

//        printf( "Entered tiltforward function tilt z0,z1,v[21] (%f,%f, %f)\n", z0, z1, v[2]);

        //	printf( "Entered invtiltb function in (%6.2f %6.2f) out (%6.2f %6.2f)\n", x_dest, y_dest, *x_src, *y_src);

	// Uncommenting code below causes tilt function to do nothing:
	//		*x_src	= x_dest;	
	//		*y_src  = y_dest;
    return 1;
}

int shear( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
	// params: double shear_horizontal, double shear_vertical;
  //	printf( "Entered shear function \n");


		*x_src  = x_dest + var0 * y_dest;
		*y_src  = y_dest + var1 * x_dest;
    return 1;
}

int shearInv( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
	// params: double shear_horizontal, double shear_vertical;
  //	printf( "Entered shear inv function \n");


    *y_src  = (y_dest - var1 * x_dest) / (1 - var1 * var0);
    *x_src  = (x_dest - var0 * *y_src);
    return 1;
}

int horiz( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
	// params: double horizontal shift

		*x_src	= x_dest + shift;	
		*y_src  = y_dest;
    return 1;
}

int vert( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
	// params: double vertical shift

		*x_src	= x_dest;	
		*y_src  = y_dest + shift;		
    return 1;
}

	
int radial( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
	// params: double coefficients[4], scale, correction_radius

	register double r, scale;

	r 		= (sqrt( x_dest*x_dest + y_dest*y_dest )) / ((double*)params)[4];
	if( r < ((double*)params)[5] )
	{
		scale 	= ((((double*)params)[3] * r + ((double*)params)[2]) * r + 
				((double*)params)[1]) * r + ((double*)params)[0];
	}
	else
		scale = 1000.0;
	
	*x_src = x_dest * scale  ;
	*y_src = y_dest * scale  ;
    return 1;
}

int vertical( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
	// params: double coefficients[4]

	register double r, scale;

	r 		= y_dest / ((double*)params)[4];

	if( r < 0.0 ) r = -r;

	scale 	= ((((double*)params)[3] * r + ((double*)params)[2]) * r + 
				((double*)params)[1]) * r + ((double*)params)[0];
	
	*x_src = x_dest;
	*y_src = y_dest * scale  ;
    return 1;
}

int deregister( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
	// params: double coefficients[4]

	register double r, scale;

	r 		= y_dest / ((double*)params)[4];

	if( r < 0.0 ) r = -r;

	scale 	= (((double*)params)[3] * r + ((double*)params)[2]) * r + 
				((double*)params)[1] ;
	
	*x_src = x_dest + abs( y_dest ) * scale;
	*y_src = y_dest ;
    return 1;
}



	
int persp_sphere( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params :  double Matrix[3][3], double distanceparam

	register double theta,s,r;
	double v[3];

#if 0	// old 
	theta = sqrt( x_dest * x_dest + y_dest * y_dest ) / *((double*) ((void**)params)[1]);
	phi   = atan2( y_dest , x_dest );

	v[0] = *((double*) ((void**)params)[1]) * sin( theta ) * cos( phi );
	v[1] = *((double*) ((void**)params)[1]) * sin( theta ) * sin( phi );
	v[2] = *((double*) ((void**)params)[1]) * cos( theta );
	
	matrix_inv_mult( (double(*)[3]) ((void**)params)[0], v );

	theta = atan2( sqrt( v[0]*v[0] + v[1]*v[1] ), v[2] );
	phi   = atan2( v[1], v[0] );
	*x_src = *((double*) ((void**)params)[1]) * theta * cos( phi );
	*y_src = *((double*) ((void**)params)[1]) * theta * sin( phi );
#endif

	r 		= sqrt( x_dest * x_dest + y_dest * y_dest );
	theta 	= r / *((double*) ((void**)params)[1]);
	if( r == 0.0 )
		s = 0.0;
	else
		s = sin( theta ) / r;

	v[0] =  s * x_dest ;
	v[1] =  s * y_dest ;
	v[2] =  cos( theta );

	matrix_inv_mult( (double(*)[3]) ((void**)params)[0], v );

	r 		= sqrt( v[0]*v[0] + v[1]*v[1] );
	if( r == 0.0 )
		theta = 0.0;
	else
		theta 	= *((double*) ((void**)params)[1]) * atan2( r, v[2] ) / r;
	*x_src 	= theta * v[0];
	*y_src 	= theta * v[1];

    return 1;
}	

int persp_rect( double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
	// params :  double Matrix[3][3], double distanceparam, double x-offset, double y-offset

	double v[3];
	
	v[0] = x_dest + *((double*) ((void**)params)[2]);
	v[1] = y_dest + *((double*) ((void**)params)[3]);
	v[2] = *((double*) ((void**)params)[1]);
	
	matrix_inv_mult( (double(*)[3]) ((void**)params)[0], v );
	
	*x_src = v[0] * *((double*) ((void**)params)[1]) / v[2] ;
	*y_src = v[1] * *((double*) ((void**)params)[1]) / v[2] ;
    return 1;
}



int rect_pano( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{									
								
	*x_src = distanceparam * tan( x_dest / distanceparam ) ;
	*y_src = y_dest / cos( x_dest / distanceparam );
    return 1;
}

int pano_rect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{	
	*x_src = distanceparam * atan ( x_dest / distanceparam );
	*y_src = y_dest * cos( *x_src / distanceparam );
    return 1;
}

int rect_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{	
	// params: double distanceparam

	register double  phi, theta;

	phi 	= x_dest / distanceparam;
	theta 	=  - y_dest / distanceparam  + PI / 2.0;
	if(theta < 0)
	{
		theta = - theta;
		phi += PI;
	}
	if(theta > PI)
	{
		theta = PI - (theta - PI);
		phi += PI;
	}

#if 0
	v[2] = *((double*)params) * sin( theta ) * cos( phi );   //  x' -> z
	v[0] = *((double*)params) * sin( theta ) * sin( phi );	//  y' -> x
	v[1] = *((double*)params) * cos( theta );				//  z' -> y
	
	phi   = atan2( v[1], v[0] );
//  old:	
//	theta = atan2( sqrt( v[0]*v[0] + v[1]*v[1] ) , v[2] );
//	rho = *((double*)params) * tan( theta );
//  new:
	rho = *((double*)params) * sqrt( v[0]*v[0] + v[1]*v[1] ) / v[2];
	*x_src = rho * cos( phi );
	*y_src = rho * sin( phi );
#endif
#if 1
	*x_src = distanceparam * tan(phi);
	*y_src = distanceparam / (tan( theta ) * cos(phi));
#endif
	// normalize phi to be in the -PI, PI range
	while(phi <= -PI)
		phi += 2*PI;
	while(phi > PI)
		phi -= 2*PI;

	// check if the point is "in front" of the camera
	if (phi < -PI/2.0 || phi > PI/2.0) {
		// behind, transform considered invalid
		return 0;
	} else
		return 1;
	// normalize phi to be in the -PI, PI range
	while(phi <= -PI)
		phi += 2*PI;
	while(phi > PI)
		phi -= 2*PI;

	// check if the point is "in front" of the camera
	if (phi < -PI/2.0 || phi > PI/2.0) {
		// behind, transform considered invalid
		return 0;
	} else
		return 1;

}
// This is the cylindrical projection
int pano_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{	
	// params: double distanceparam

	*x_src = x_dest;
	*y_src = distanceparam * tan( y_dest / distanceparam);
    return 1;
}

int erect_pano( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{	
	// params: double distanceparam

	*x_src = x_dest;
	*y_src = distanceparam * atan( y_dest / distanceparam);
    return 1;
}

/** convert from erect to lambert azimuthal */
int lambertazimuthal_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    // params: distanceparam
    double phi, lambda,k1;
    lambda = x_dest/distanceparam;
    phi = y_dest/distanceparam;

    if (abs(cos(phi) * cos(lambda) + 1.0) <= EPSLN) {
      *x_src = distanceparam * 2 ;
      *y_src = 0;
      return 0;
    }

    k1 = sqrt(2.0 / (1 + cos(phi) * cos(lambda)));

    *x_src = distanceparam * k1 * cos(phi) * sin (lambda);
    *y_src = distanceparam * k1 * sin(phi);

    return 1;
}

/** convert from lambert azimuthal to erect */
int erect_lambertazimuthal( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{

    double x, y, ro,c;

    x = x_dest/distanceparam;
    y = y_dest/distanceparam;

    assert(! isnan(x));
    assert(! isnan(y));

    if (fabs(x) > PI || fabs(y) > PI) {
        *y_src = 0;
        *x_src = 0;
	return 0;
    }

    ro = hypot(x, y);

    if (fabs(ro) <= EPSLN)
    {
        *y_src = 0;
        *x_src = 0;
        return 1;
    }

    c = 2 * asin(ro / 2.0);

    *y_src = distanceparam * asin( (y * sin(c)) / ro);


    if (fabs(ro * cos(c)) <= EPSLN ) {
      *x_src = 0;
      return 1;
    }

    *x_src = distanceparam * atan2( x * sin(c), (ro * cos(c)));

    return 1;
}

/** convert from erect to hammer */
int hammer_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    if(lambertazimuthal_erect(x_dest/2.0, y_dest, x_src, y_src, params))
    {
        *x_src *= 2.0;
        return 1;
    }
    else
    {
        *x_src=0;
        *y_src=0;
        return 0;
    };
}

/** convert from hammer to erect */
int erect_hammer( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    double x, y, z;
    x = x_dest/distanceparam;
    y = y_dest/distanceparam;
    z = 1.0 - (x * x / 16.0) - (y * y / 4.0);
    if(z<0)
    {
        *x_src=0;
        *y_src=0;
        return 0;
    };
    z = sqrt(z);
    *x_src = 2.0 * atan2(z*x, 2.0*(2.0*z*z-1.0));
    *y_src = asin(y*z);
    if(fabs(*x_src) > PI || fabs(*y_src) > HALF_PI)
    {
        *x_src=0;
        *y_src=0;
        return 0;
    };
    *x_src *= distanceparam;
    *y_src *= distanceparam;
    return 1;
}

/** convert from erect to mercator FORWARD */
int mercator_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    // params: distanceparam
    *x_src = x_dest;
    *y_src = distanceparam*log(tan(y_dest/distanceparam)+1/cos(y_dest/distanceparam));
    return 1;
}

/** convert from mercator to erect INVERSE */
int erect_mercator( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    // params: distanceparam
    *x_src = x_dest;
    *y_src = distanceparam*atan(sinh(y_dest/distanceparam));
    return 1;
}


/** convert from erect to miller */
int millercylindrical_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    // params: distanceparam
    double phi, tanPhi;

    *x_src = x_dest;
    phi = y_dest/distanceparam;
    tanPhi = tan(PI/4 +0.4 * phi);
    if (tanPhi < 0) {
        *x_src = 0;
        *y_src = 0;
        return 0;
    };    
    *y_src = distanceparam*log(tanPhi)/0.8;
    return 1;
}

/** convert from erect to miller */
int arch_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    // params: distanceparam
    if (y_dest < 0) {
        return millercylindrical_erect(x_dest, y_dest, x_src, y_src, params);
    } else {
        return lambert_erect(x_dest, y_dest, x_src, y_src, params);
    }
}

/** convert from erect to miller */
int erect_arch( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    // params: distanceparam
    if (y_dest < 0) {
        return erect_millercylindrical(x_dest, y_dest, x_src, y_src, params);
    } else {
        return erect_lambert(x_dest, y_dest, x_src, y_src, params);
    }
}



/** convert from miller cylindrical to erect */
int erect_millercylindrical( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    double y;

    *x_src = x_dest;
    y = y_dest/distanceparam;
    y = 1.25 * atan(sinh(4 * y /5.0));
    if ( fabs(y) > HALF_PI) {
        *x_src = 0;
        *y_src = 0;
        return 0;
    };
    *y_src = distanceparam * y;
    return 1;
}


/** convert from erect to panini */
int panini_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    // params: distanceparam
  // this is the inverse

    double phi, lambdaHalf, temp,y,x;

    phi = y_dest/distanceparam;
    lambdaHalf = x_dest/ (distanceparam*2);
    x = 2 * tan (lambdaHalf);

    // Conver from central cylindrical
    phi = tan(phi);

    *x_src = distanceparam * x;
    temp  = cos(lambdaHalf);
    
    y = tan(phi) / (temp * temp);
    
    // At this point we have mapped to central cylindrical, now to equirectangular
      
    *y_src = distanceparam *  y;

    return 1;
}

/** General Pannini Projection

  setup_panini_general(&MakeParams) selects the Image struct
  corresponding to the pannini_general image and returns its
  address, or a NULL pointer for failure.

  If the selected Image has an invalid precomputedCount, it
  posts the distanceparam corresponding to min( max feasible
  hFOV, requested hFOV) and puts working parameter values in 
  precomputeValue[] in the selected Image.

  SetMakeParams (adjust.c) calls this function in lieu of setting
  distanceparam.

  The user-visible projection params, described in queryfeature.c, 
  are scaled to accomodate integer-valued control sliders in a GUI.  
  unscaleParams_panini_general() sets working values as follows:
    cmpr 0:100:150 <-> d = 0:1:->infinity NOTE very nonlinear
    tops, bots -100:100 <-> sqz -1:1 linear
				< 0 gives soft squeeze
				> 0 give transverse straightening squeeze
  CAUTION these ranges are assumed, not read from queryfeature.c

  maxFOVs_panini_general() calculates the maximum feasible FOVs
  for a given scaled parameter set.   Those also depends on a 
  projection angle limit, that is hard coded here.  FOVs in degrees.

**/
#define MAX_PROJ_ANGLE 80	

int unscaleParams_panini_general( 
				double * gui_params,	// cmpr, tops, bots
				double * wrk_params		// d, t, b
							    )
{
	double t;

   /* check for legal values */
    if(    gui_params[0] < 0
		|| gui_params[0] > 150
	  ) return 0;
    if(    gui_params[1] < -100
		|| gui_params[1] > 100
	  ) return 0;
    if(    gui_params[2] < -100
		|| gui_params[2] > 100
	  ) return 0;

    /* post working param values */
    t = (150 - gui_params[0]) / 50;	/* 0:150 => 3:0 */
    wrk_params[0] = 1.5 / (t + 0.0001) - 1.5/3.0001;
    wrk_params[1] = gui_params[1] / 100;
    wrk_params[2] = gui_params[2] / 100;

	return 1;
}

int maxFOVs_panini_general	( double *params, double *fovs ){
	double wparams[3], mfovs[2];
  /* translate user params to working values */
	if( !unscaleParams_panini_general( params, wparams )
	  )
	  return 0;
  /* compute max half-fovs in radians */
	if( !panini_general_maxVAs( wparams[0], 
							  DEG_TO_RAD(MAX_PROJ_ANGLE),
							  mfovs
							 )
	  )
	  return 0;

 /* return full fovs in degrees */
	fovs[0] = 2 * RAD_TO_DEG(mfovs[0]);
	fovs[1] = 2 * RAD_TO_DEG(mfovs[1]);

	return 1;
}

Image * setup_panini_general(struct MakeParams* pmp)
{	int  i; 
    double s,t,d,v, vl[2];
    Image * ppg = NULL;

    // Only act if it is panini_general 
    if( pmp->im->format == _panini_general )  // input panini --is it supported?
        ppg = pmp->im;
    else if( pmp->pn->format == _panini_general ) // output panini
        ppg = pmp->pn;
    else 
        return NULL;

    /* check number of precomputed param values */
    if( ppg->precomputedCount == 7 )
		return ppg;		// OK
	
    /* default unspecified values to 0, giving 
		stereographic compresssion (d = 1)
		and no squeezes.
	*/
    for( i = ppg->formatParamCount; i < 3; i++ ) 
        ppg->formatParam[i] = 0;

  /* translate user params to working values */
	if( !unscaleParams_panini_general( ppg->formatParam, ppg->precomputedValue )
	  )
	  return NULL;
	d = ppg->precomputedValue[0];

  /* get max feasible half-FOVs */
	if( !panini_general_maxVAs( d,
								DEG_TO_RAD( 80 ),	// max projection angle
								vl					// max view angles h, v
							  )
	  )
	  return 0;

  // angle and coordinate limits
	s = (d + 1) / (d + cos(vl[0]));
	ppg->precomputedValue[3] = vl[0];	// max lambda
	ppg->precomputedValue[4] = s * sin( vl[0] );	// max x 
	ppg->precomputedValue[5] = vl[1];	// max phi
	ppg->precomputedValue[6] = s * tan( vl[1] );	// max y 

  // clip hFOV to feasible limit
	v = 0.5 * DEG_TO_RAD( ppg->hfov );
	if( v > vl[0] )
		v = vl[0];

  // set distance param
	t = sin(v) * (d+1) / (d + cos(v));
	pmp->distance = 0.5 * ppg->width / t;
       
	ppg->precomputedCount = 7; 
    return ppg;
}

/** convert from panini_general to erect **/
int erect_panini_general( double x_dest,double  y_dest, double* lambda_src, double* phi_src, void* params)
{  /* params -> MakeParams */
    double x, y, lambda, phi, distance;
    
    Image * ppg = setup_panini_general(mp);
    if( !ppg ) 
        return FALSE;

    distance = mp->distance;
    y = y_dest/distance;
    x = x_dest/distance;

  // fail if outside max image
/*	if(  fabs(x) > ppg->precomputedValue[4] 
	  || fabs(y) > ppg->precomputedValue[6]
	  )
	  return 0;	
*/
  // call mapping fn
	if( !panini_general_toSphere( &lambda, &phi, x, y,
								 ppg->precomputedValue[0],
								 ppg->precomputedValue[1],
								 ppg->precomputedValue[2])
	  )
	  return 0;
	    
 	*lambda_src = lambda * distance;
	*phi_src = phi * distance;
    
	return TRUE;
}


	/** convert from erect to panini_general **/
int panini_general_erect( double lambda_dest,double  phi_dest, double* x_src, double* y_src, void* params)
{
	/* params -> MakeParams */

	double phi, lambda, y,x;
	double distance;

	Image * ppg = setup_panini_general(mp);
	if( !ppg ) 
		return 0;

	distance = mp->distance;
	lambda = lambda_dest/distance;
	phi = phi_dest/distance;

  // fail if outside feasible FOV
/*	if(  fabs(lambda) > ppg->precomputedValue[3] 
	  || fabs(phi) > ppg->precomputedValue[5]
	  )
	  return 0;	
*/
  // call mapping fn
	if( !panini_general_toPlane( lambda, phi, &x, &y,
								 ppg->precomputedValue[0],
								 ppg->precomputedValue[1],
								 ppg->precomputedValue[2])
	  )
	  return 0;

  // fail if coords outside max image (needed for squeeze)
/*	if(  fabs(x) > ppg->precomputedValue[4] 
	  || fabs(y) > ppg->precomputedValue[6]
	  )
	  return 0;	
*/
	*y_src = distance * y;
    *x_src = distance * x;
    return 1;
}

/** convert from panini to erect */
int erect_panini( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    double y;
    double x;
    double temp;

    double  lambda;

    double phi;
    y = y_dest/distanceparam;
    x = x_dest/distanceparam;
    lambda = atan(x/2);
 
    // then project from opposite edge of the cylinder
    temp = cos(lambda);
    phi = y * temp * temp;

    // First convert to central cylindrical
    phi  = atan( phi);

    *x_src = 2 * lambda * distanceparam;
    *y_src = atan(phi) * distanceparam;

    return 1;
}




/** convert from erect to equi panini */
int equipanini_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    // params: distanceparam
  // this is the inverse

    double phi, lambdaHalf, temp,y,x;

    phi = y_dest/distanceparam;
    lambdaHalf = x_dest/ (distanceparam*2);
    x = 2 * tan (lambdaHalf);

    *x_src = distanceparam * x;
    temp  = cos(lambdaHalf);
    
    y = tan(phi) / (temp * temp);

    // At this point we have mapped to central cylindrical, now to equirectangular
      
    *y_src = distanceparam *  y;

    return 1;
}


/** convert from equi panini to erect */
int erect_equipanini( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    double y;
    double x;
    double temp;

    double  lambda;

    double phi;
    y = y_dest/distanceparam;
    x = x_dest/distanceparam;
    lambda = atan(x/2);
 
    // then project from opposite edge of the cylinder
    temp = cos(lambda);
    phi = y * temp * temp;

    *x_src = 2 * lambda * distanceparam;
    *y_src = atan(phi) * distanceparam;

    return 1;
}





/** convert from erect to lambert */
int lambert_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    // params: distanceparam
    *x_src = x_dest;
    *y_src = distanceparam*sin(y_dest/distanceparam);
    return 1;
}

/** convert from lambert to erect */
int erect_lambert( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    // params: distanceparam
    double y;
    *x_src = x_dest;
    y = y_dest / distanceparam;
    if (fabs(y) > 1) {
        *x_src = 0;
        *y_src = 0;
        return 0;
    };
    *y_src = distanceparam*asin(y);
    return 1;
}


/** convert from erect to transverse mercator */
int transmercator_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void*  params)
{
    // params: distanceparam
    double B;
    x_dest /= distanceparam;
    y_dest /= distanceparam;
    B = cos(y_dest)*sin(x_dest);
    *x_src = distanceparam * atanh(B);
    *y_src = distanceparam * atan2(tan(y_dest), cos(x_dest));

    if (isinf(*x_src)) {
      return 0;
    }

    return 1;
}

/** convert from erect to transverse mercator */
int erect_transmercator( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
    // params: distanceparam
    x_dest /= distanceparam;
    y_dest /= distanceparam;

    if (fabs(y_dest) > PI ) {
        *y_src = 0;
        *x_src = 0;
	return 0;
    }


    *x_src = distanceparam * atan2(sinh(x_dest),cos(y_dest));
    *y_src = distanceparam * asin(sin(y_dest)/cosh(x_dest));
    return 1;
}

/** convert from erect to sinusoidal */
int sinusoidal_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void*  params)
{
    // params: distanceparam

    *x_src = distanceparam * (x_dest/distanceparam*cos(y_dest/distanceparam));
    *y_src = y_dest;
    return 1;
}

/** convert from sinusoidal to erect */
int erect_sinusoidal( double x_dest,double  y_dest, double* x_src, double* y_src, void*  params)
{
    // params: distanceparam

    *y_src = y_dest;
    *x_src = x_dest/cos(y_dest/distanceparam);
    if (*x_src/distanceparam < -PI || *x_src/distanceparam > PI)
	return 0; 
    return 1;
}

/** convert from erect to stereographic */
int stereographic_erect_old( double x_dest,double  y_dest, double* x_src, double* y_src, void*  params)
{
    // params: distanceparam
    double lon = x_dest / distanceparam;
    double lat = y_dest / distanceparam;

    // use: R = 1
    double k=2.0/(1+cos(lat)*cos(lon));
    *x_src = distanceparam * k*cos(lat)*sin(lon);
    *y_src = distanceparam * k*sin(lat);
    return 1;
}

int stereographic_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void*  params)
{
    double lon, lat;
    double sinphi, cosphi, coslon;
    double g,ksp;

    lon = x_dest / distanceparam;
    lat = y_dest / distanceparam;

    sinphi = sin(lat);
    cosphi = cos(lat);
    coslon = cos(lon);

    g = cosphi * coslon;

    // point projects to infinity:
    //    if (fabs(g + 1.0) <= EPSLN)

    ksp = distanceparam * 2.0 / (1.0 + g);
    *x_src = ksp * cosphi * sin(lon);
    *y_src = ksp * sinphi;

    return 1;
}

/** convert from stereographic to erect */
int erect_stereographic( double x_dest,double  y_dest, double* lon, double* lat, void*  params)
{
    double rh;		/* height above sphere*/
    double c;		/* angle					*/
    double sinc,cosc;	/* sin of c and cos of c			*/

    /* Inverse equations
     -----------------*/
    double x = x_dest / distanceparam;
    double y = y_dest / distanceparam;
    rh = sqrt(x * x + y * y);
    c = 2.0 * atan(rh / (2.0 * 1));
    sinc = sin(c);
    cosc = cos(c);
    *lon = 0;
    if (fabs(rh) <= EPSLN)
    {
        *lat = 0;
        return 0;
    }
    else
    {
        *lat = asin((y * sinc) / rh) * distanceparam;

        if ((fabs(cosc) < EPSLN) && (fabs(x) < EPSLN))
            return 0;
        else
            *lon = atan2((x * sinc), (cosc * rh)) * distanceparam;
    }
    return 1;
}


/** convert from stereographic to erect */
int erect_stereographic_old( double x_dest,double  y_dest, double* x_src, double* y_src, void*  params)
{
    // params: distanceparam

    // use: R = 1
    double p=sqrt(x_dest*x_dest + y_dest*y_dest) / distanceparam;
    double c= 2.0*atan(p/2.0);

    *x_src = distanceparam * atan2(x_dest/distanceparam*sin(c),(p*cos(c)));
    *y_src = distanceparam * asin(y_dest/distanceparam*sin(c)/p);
    return 1;
}

int albersEqualAreaConic_ParamCheck(Image *im) 
{
    //Parameters: phi1, phi2, phi0, n, C, rho0, yoffset
    // Albers Equal-Area Conic Projection
    // parameters phi0, phi1, phi2:
    //   latitude values
    // parameter n:
    //   (latex) $\frac{1}{2}\left(\sin\phi_1 + \sin\phi_2\right)$
    //   (C) (sin(phi1) + sin(phi2)) / 2.0
    // parameter C:
    //   (latex) $\cos^2\phi_1 + 2 n \sin\phi_1$
    //   (C) cos(phi1) * cos(phi1) + 2.0 * n * sin(phi1)
    // parameter rho0:
    //   (latex) $\frac{\sqrt{C - 2 n \sin\phi_0}}{n}$
    //   (C) sqrt(C - 2.0 * n * sin(phi0))
    // yoffset:
    //   offset in y-direction for centering

    double phi0, phi1, phi2, n, C, rho0, yoffset;
    double Aux_2N; /* auxiliary variable for (2 * n) */
    double Aux_sin_phi0; /* auxiliary variable for sin(phi0) */
    double Aux_sin_phi1; /* auxiliary variable for sin(phi1) */
    double Aux_sin_phi2; /* auxiliary variable for sin(phi2) */
    double Aux_yl, Aux_yo; /* auxiliary variables for lower and upper y value */
    double Aux_1; /* auxiliary variable */
    double phi[] = {-PI/2, 0, PI/2};
    double lambda[] = {-PI, 0, PI};
    int i, j, first;

    assert(PANO_PROJECTION_MAX_PARMS >= 2);

    if (im->formatParamCount == 1) {
        // When only one parameter provided, assume phi1 = phi0
	im->formatParamCount = 2;
	im->formatParam[1] = im->formatParam[0];
    }

    if (im->formatParamCount == 0) {
        // if no latitude values given, then set defaults
	im->formatParamCount = 2;
	im->formatParam[0] = 0;  //phi1
	im->formatParam[1] = -60; //phi2
    }

    if (im->precomputedCount == 0) {
	im->precomputedCount = 10;

	assert(PANO_PROJECTION_PRECOMPUTED_VALUES >=im->precomputedCount );


	// First, invert standard parallels. 
	// This is a hack, as the resulting projections look backwards to what they are supposed to be
	// (with respect to maps)
	
	im->precomputedValue[0] =  -1.0 * im->formatParam[0];
	im->precomputedValue[1] =  -1.0 * im->formatParam[1];

        phi0 = 0; // default value of phi0
	phi1 = im->precomputedValue[0] * PI / 180.0; //phi1 to rad
	phi2 = im->precomputedValue[1] * PI / 180.0; //phi2 to rad

        // precompute sinus functions
        Aux_sin_phi0 = sin(phi0);
        Aux_sin_phi1 = sin(phi1);
        Aux_sin_phi2 = sin(phi2);
        // precompute auxiliary term (2 * n)
        Aux_2N = Aux_sin_phi1 + Aux_sin_phi2;

        // calculate parameters
        // The stability of these operations should be improved
        n = Aux_2N / 2.0;
        C = 1.0 + Aux_sin_phi1 * Aux_sin_phi2;
        Aux_1 = (C - (Aux_2N * Aux_sin_phi0));
        Aux_1 = ( (Aux_1 > 0.0) ? (sqrt(Aux_1)) : (0.0) );
        rho0 = ( (n != 0.0) ? (Aux_1 / n) : (1.7E+308) );

        // calculate the y at 6 different positions (lambda=-pi,0,+pi; phi=-pi/2,0,pi/2).
	///Then calculate a yoffset so that the image is centered.
	first = 1;
        for (i = 0; i < 3; i++) {
            for (j = 0; j < 3; j++) {
                Aux_1 = C - (sin(phi[i]) * Aux_2N);
                if (C >= 0.0 && Aux_1 >= 0.0 && n != 0.0) {
                    Aux_1 = (sqrt(C) - (sqrt(Aux_1) * cos(n * lambda[j]))) / n;
                    if (first || Aux_1 < Aux_yl) {
                        Aux_yl = Aux_1;
                    }
                    if (first || Aux_1 > Aux_yo) {
                        Aux_yo = Aux_1;
                    }
		first = 0;
	    }
	}
        }
	if (first) {
            yoffset = 0.0;
        }
        else {
            yoffset = Aux_yl + fabs(Aux_yl - Aux_yo) / 2.0;
	}

	im->precomputedValue[0] = phi1;
	im->precomputedValue[1] = phi2;
	im->precomputedValue[2] = phi0;
	im->precomputedValue[3] = n;
	im->precomputedValue[4] = C;
	im->precomputedValue[5] = rho0;
        im->precomputedValue[6] = yoffset;
	im->precomputedValue[7] = n*n;
        im->precomputedValue[8] = Aux_2N;
        im->precomputedValue[9] = Aux_2N;

	//	printf("Parms phi1 %f phi2 %f pho0 %f, n %f, C %f, rho0 %f, %f\n", 
	//	       phi1, phi2, phi0, n, C, rho0, y);

    }

    for (i=0;i<im->precomputedCount;i++) {
	assert(!isnan(im->precomputedValue[i]));
    }
    
    if (im->precomputedCount > 0) {
        return 1;
    }
    //    PrintError("false in alberts equal area parameters");
    return 0;
}

/** convert from erect to albersequalareaconic */
int albersequalareaconic_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void *params)
{
    double yoffset, lambda, phi, lambda0, n, C, rho0, theta, rho;
    double twiceN;

    // Forward calculation


    if (!albersEqualAreaConic_ParamCheck(mp->pn))  {
	//	printf("REturning abert->erect 0\n");
	return 0;
    }

    assert(!isnan(x_dest));
    assert(!isnan(y_dest));

    lambda = x_dest / mp->distance;
    phi = y_dest / mp->distance;

    if (lambda > PI) lambda-=2*PI;
    if (lambda < -PI) lambda+=2*PI;

    lambda0 = 0;

    n = mp->pn->precomputedValue[3];
    C = mp->pn->precomputedValue[4];
    rho0 = mp->pn->precomputedValue[5];
    yoffset = mp->pn->precomputedValue[6];
    twiceN = mp->pn->precomputedValue[9];

    theta = n * (lambda - lambda0);

    
    //    printf("value %f\n", (phi));
    //    printf("value %f\n", sin(phi));
    //    printf("value %f\n", C - 2.0 * n * sin(phi));
    //assert(C - 2.0 * n * sin(phi) >=0);
    rho = sqrt(C - twiceN * sin(phi)) / n;

    *x_src = mp->distance * (rho * sin(theta));
    *y_src = mp->distance * (rho0 - rho * cos(theta) - yoffset);

    if (isnan(*x_src) ||
	isnan(*y_src)) {
	*x_src = 0;
	*y_src = 0;
	//	PrintError("false in alberts equal area 4");
	return 0;
    }

    assert(!isnan(*x_src));
    assert(!isnan(*y_src));

    return 1;
}

/** convert from albersequalareaconic to erect */
int erect_albersequalareaconic(double x_dest, double y_dest, double* x_src, double* y_src, void* params)
{
    double x, y, yoffset, lambda0, n, C, rho0, theta, phi, lambda, nsign;
    double rho2; // rho^2
    double n2; // n^2
    double twiceN; // n * 2.0
    
    //  Inverse calculation

    if (!albersEqualAreaConic_ParamCheck(mp->pn))  {
	*x_src = 0;
	*y_src = 0;
	//	printf("false in alberts equal area\n");
	return 0;
    }

    x = x_dest / mp->distance;
    y = y_dest / mp->distance;

    lambda0 = 0;

    n = mp->pn->precomputedValue[3];
    C = mp->pn->precomputedValue[4];
    rho0 = mp->pn->precomputedValue[5];
    yoffset = mp->pn->precomputedValue[6];
    n2 = mp->pn->precomputedValue[7];
    twiceN = mp->pn->precomputedValue[9];

    y = y + yoffset;

    rho2 = x*x + (rho0 - y)*(rho0 - y);
    nsign = 1.0;

    if (n < 0) nsign = -1.0;

    theta = atan2(nsign * x, nsign * (rho0 - y));

    phi = asin((C - rho2 * n2)/twiceN);

    lambda = lambda0 + theta / n;
    if (lambda > PI || lambda < -PI)  {
	*x_src = 0;
	*y_src = 0;
	//	PrintError("false in alberts equal area 2");
	return 0;
    }

    *x_src = mp->distance * lambda;
    *y_src = mp->distance * phi;

    if (isnan(*x_src) ||  
	isnan(*y_src)) {
	*x_src = 0;
	*y_src = 0;
	//	PrintError("false in alberts equal area 3");
	return 0;
    }

    assert(!isnan(*x_src));
    assert(!isnan(*y_src));

    return 1;
}

int albersequalareaconic_distance(double* x_src, void* params) {
    double x1, x2, y, phi1, phi2, lambda;

    //    printf("alber distance\n");

    if (!albersEqualAreaConic_ParamCheck(mp->pn))  {
	*x_src = 0;
	//	printf("false in alberts equal area distance 0\n");
	return 0;
    }

    mp->distance = 1;
    phi1 = mp->pn->precomputedValue[0];
    phi2 = mp->pn->precomputedValue[1];

    //lambda where x is a maximum.
    if ( (phi1 == phi2 && phi1 == 0.0) 
        || (phi1 == -phi2) )
    {
	// THIS IS A HACK...it needs to further studied
	// why this when phi1==phi2==0 
	// this functions return 0
	// Avoid approximation error
	// PrintError("The Albers projection cannot be used for phi1==phi2==0. Use Lambert Cylindrical Equal Area instead");

	*x_src = PI;
	return 0;
    }
    lambda = fabs(PI / (sin(phi1) + sin(phi2)));
    if (lambda > PI) lambda = PI;
    albersequalareaconic_erect(lambda, -PI/2.0, &x1, &y, mp);
    albersequalareaconic_erect(lambda, PI/2.0, &x2, &y, mp);
    *x_src = max(fabs(x1), fabs(x2));

    if (isnan(*x_src))  {
	*x_src = 0;
	PrintError("false in alberts equal area distance 1");
	return 0;
    }

    assert(!isnan(*x_src));

    //    printf("return albers distance %f\n", *x_src);

    return 1;

}


int sphere_cp_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam, double b

	register double phi, theta;
	phi 	= - x_dest /  ( var0 * PI / 2.0);
	theta 	=  - ( y_dest + var1 ) / ( PI / 2.0) ;
	
	*x_src =  theta * cos( phi );
	*y_src =  theta * sin( phi );
    return 1;
}


int sphere_tp_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam

	register double phi, theta, r,s;
	double v[3];

	phi 	= x_dest / distanceparam;
	theta 	=  - y_dest / distanceparam  + PI / 2;
	if(theta < 0)
	{
		theta = - theta;
		phi += PI;
	}
	if(theta > PI)
	{
		theta = PI - (theta - PI);
		phi += PI;
	}


	s = sin( theta );
	v[0] =  s * sin( phi );	//  y' -> x
	v[1] =  cos( theta );				//  z' -> y
	
	r = sqrt( v[1]*v[1] + v[0]*v[0]);	

	theta = distanceparam * atan2( r , s * cos( phi ) );
	
	*x_src =  theta * v[0] / r;
	*y_src =  theta * v[1] / r;
    return 1;
}


int erect_sphere_cp( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam, double b

	register double phi, theta;

#if 0
	theta = sqrt( x_dest * x_dest + y_dest * y_dest ) / var0;
	phi   = atan2( y_dest , -x_dest );
	
	*x_src = var0 * phi;
	*y_src = var0 * theta - var1;
#endif
	theta = sqrt( x_dest * x_dest + y_dest * y_dest ) ;
	phi   = atan2( y_dest , -x_dest );
	
	*x_src = var0 * phi;
	*y_src = theta - var1;
    return 1;
}


int rect_sphere_tp( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam

	register double rho, theta,r;

#if 0	
	theta = sqrt( x_dest * x_dest + y_dest * y_dest ) / distanceparam;
	phi   = atan2( y_dest , x_dest );
	
	if( theta > PI /2.0  ||  theta < -PI /2.0 )
		theta = PI /2.0 ;

	rho = distanceparam * tan( theta );

	*x_src = rho * cos( phi );
	*y_src = rho * sin( phi );
#endif
	r 		= sqrt( x_dest * x_dest + y_dest * y_dest );
	theta 	= r / distanceparam;
	
	if( theta >= PI /2.0   )
		rho = 1.6e16 ;
	else if( theta == 0.0 )
		rho = 1.0;
	else
		rho =  tan( theta ) / theta;
	*x_src = rho * x_dest ;
	*y_src = rho * y_dest ;
    return 1;
}


int sphere_tp_rect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{	
	// params: double distanceparam

	register double  theta, r;

#if 0	
	theta = atan( sqrt(x_dest*x_dest + y_dest*y_dest) / *((double*)params));
	phi   = atan2( y_dest , x_dest );
	
	*x_src = *((double*)params) * theta * cos( phi );
	*y_src = *((double*)params) * theta * sin( phi );
#endif
	r 		= sqrt(x_dest*x_dest + y_dest*y_dest) / distanceparam;
	if( r== 0.0 )
		theta = 1.0;
	else
		theta 	= atan( r ) / r;
	
	*x_src =  theta * x_dest ;
	*y_src =  theta * y_dest ;
    return 1;
}


int sphere_tp_pano( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam

	register double r, s, Phi, theta;
	
#if 0
	register double Theta, phi;
	double v[3];
	
	Phi = x_dest / *((double*)params);
	Theta = PI /2.0 - atan( y_dest / distanceparam );
	

	v[2] = *((double*)params) * sin( Theta ) * cos( Phi );   //  x' -> z
	v[0] = *((double*)params) * sin( Theta ) * sin( Phi );	//  y' -> x
	v[1] = *((double*)params) * cos( Theta );				//  z' -> y
	
	theta = atan2( sqrt( v[0]*v[0] + v[1]*v[1] ) , v[2] );
	phi   = atan2( v[1], v[0] );
	
	*x_src = *((double*)params) * theta * cos( phi );
	*y_src = *((double*)params) * theta * sin( phi );
#endif
#if 1
	Phi = x_dest / distanceparam;
		
	s =  distanceparam * sin( Phi ) ;	//  y' -> x
	
	r = sqrt( s*s + y_dest*y_dest );
	theta = distanceparam * atan2( r , (distanceparam * cos( Phi )) ) / r;
	
	*x_src =  theta * s ;
	*y_src =  theta * y_dest ;
#endif
    return 1;
}


int pano_sphere_tp( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam
	register double r,s, theta;
	double v[3];

#if 0	
	theta = sqrt( x_dest * x_dest + y_dest * y_dest ) / distanceparam;
	phi   = atan2( y_dest , x_dest );

	v[1] = *((double*)params) * sin( theta ) * cos( phi );   //  x' -> y
	v[2] = *((double*)params) * sin( theta ) * sin( phi );	//  y' -> z
	v[0] = *((double*)params) * cos( theta );				//  z' -> x

	theta = atan2( sqrt( v[0]*v[0] + v[1]*v[1] ) , v[2] );
	phi   = atan2( v[1], v[0] );

	*x_src = *((double*)params) * phi;
	*y_src = *((double*)params) * tan( (-theta + PI /2.0) );
#endif
	
	r = sqrt( x_dest * x_dest + y_dest * y_dest );
	theta = r / distanceparam;
	if( theta == 0.0 )
		s = 1.0 / distanceparam;
	else
		s = sin( theta ) /r;

	v[1] =  s * x_dest ;   //  x' -> y
	v[0] =  cos( theta );				//  z' -> x


	*x_src = distanceparam * atan2( v[1], v[0] );
	*y_src = distanceparam * s * y_dest / sqrt( v[0]*v[0] + v[1]*v[1] );

    return 1;
}


int sphere_cp_pano( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam

	register double phi, theta;
	
	
	phi 	= -x_dest / (distanceparam * PI / 2.0) ;
	theta	= PI /2.0 + atan( y_dest / (distanceparam * PI/2.0) );

	*x_src = distanceparam * theta * cos( phi );
	*y_src = distanceparam * theta * sin( phi );
    return 1;
}


int erect_rect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam
#if 0
	theta = atan( sqrt(x_dest*x_dest + y_dest*y_dest) / distanceparam );
	phi   = atan2( y_dest , x_dest );


	v[1] = distanceparam * sin( theta ) * cos( phi );   //  x' -> y
	v[2] = distanceparam * sin( theta ) * sin( phi );	//  y' -> z
	v[0] = distanceparam * cos( theta );				//  z' -> x
	
	theta = atan2( sqrt( v[0]*v[0] + v[1]*v[1] ) , v[2] );
	phi   = atan2( v[1], v[0] );

	*x_src = distanceparam * phi;
	*y_src = distanceparam * (-theta + PI /2.0);
#endif

	*x_src = distanceparam * atan2( x_dest, distanceparam );
	*y_src = distanceparam * atan2(  y_dest, sqrt( distanceparam*distanceparam + x_dest*x_dest ) );

    return 1;
}

/** convert erect to cartesian XYZ coordinates
 */
int cart_erect( double x_dest, double y_dest, double * xyz, double distance)
{
    // phi is azimuth (negative angle around y axis, starting at the z axis)
	double phi = x_dest / distance;	
	double theta_zenith = PI/2.0 - (y_dest / distance);
	// compute cartesian coordinates..
	//pos[2] = cos(-phi)*sin(theta_zenith);
	//pos[0] = sin(-phi)*sin(theta_zenith);
	//pos[1] = cos(theta_zenith);

    xyz[0] = sin(theta_zenith)*sin(phi);
	xyz[1] = cos(theta_zenith);
	xyz[2] = sin(theta_zenith)*-cos(phi);

	return 1;
}


/** convert cartesian coordinates into spherical ones
 */
int erect_cart(double * xyz, double *x_src, double *y_src, double distance)
{
	*x_src = atan2(xyz[0],-xyz[2]) * distance;
	*y_src = asin(xyz[1]/sqrt(xyz[0]*xyz[0]+xyz[1]*xyz[1]+xyz[2]*xyz[2])) * distance;

  return 1;
}


/** Compute intersection between line and point.
 *  n : a,b,c,d coefficients of plane (a,b,c = normal vector)
 *  p1: point on line
 *  p2: point on line
 *  See http://local.wasp.uwa.edu.au/~pbourke/geometry/planeline/
 */
int line_plane_intersection(double n[4],
							double p1[3],
							double p2[3],
							double * result)
{
	int i;
	// direction vector of line
	double d[3];
	double u,num,den;

	for (i=0;i<3;i++)
		d[i] = p2[i]-p1[i];
	num = n[0]*p1[0]+n[1]*p1[1]+n[2]*p1[2] + n[3];
	den = -n[0]*d[0]-n[1]*d[1]-n[2]*d[2];
	if (fabs(den) < 1e-15) {
		return 0;
	}
	u = num/den;

	if (u < 0) {
		// This is match is in the wrong direction, ignore
		return 0;
	}
	/* printf("intersect, dir: %f %f %f, num: %f, denom: %f, u: %f\n", d[0], d[1], d[2], num, den, u);
	 */

	for (i=0;i<3;i++)
	  result[i] = p1[i]+u*d[i];

	return 1;
}

/** transfer a point from the master camera through a plane into camera 
 *  at TrX, TrY, TrZ using the plane located at Te0 (yaw), Te1 (pitch)
 */
int plane_transfer_to_camera( double x_dest, double y_dest, double * x_src, double * y_src, void * params)
{
	// params: distance, x1,y1,z1

	double plane_coeff[4];
	double p1[3];
	double p2[3];
	double intersection[3];

	// compute ray of sight for the current pixel in
	// the master panorama camera.
	// camera point
	p1[0] = p1[1] = p1[2] = 0;
	// point on sphere.
	cart_erect(x_dest, y_dest, &p2[0], mp->distance);

	// compute plane description
    cart_erect(mp->trans[3], -mp->trans[4],
			   &plane_coeff[0], 1.0);

	// plane_coeff[0..2] is both the normal and a point
	// on the plane.
	plane_coeff[3] = - plane_coeff[0]*plane_coeff[0]
		             - plane_coeff[1]*plane_coeff[1]
		             - plane_coeff[2]*plane_coeff[2];

	/*
	printf("Plane: y:%f p:%f coefficients: %f %f %f %f, ray direction: %f %f %f\n", 
	       mp->trans[3], mp->trans[4], plane_coeff[0], plane_coeff[1], plane_coeff[2], plane_coeff[3],
		   p2[0],p2[1],p2[2]);
	*/

	// perform intersection.

	if (!line_plane_intersection(plane_coeff, p1, p2, &intersection[0])) {
		// printf("No intersection found, %f %f %f\n", p2[0], p2[1], p2[2]);
		return 0;
	}

	// compute ray leading to the camera.
	intersection[0] -= mp->trans[0];
	intersection[1] -= mp->trans[1];
	intersection[2] -= mp->trans[2];

	// transform into erect
	erect_cart(&intersection[0], x_src, y_src, mp->distance);

	/*
	printf("pano->plane->cam(%.1f, %.1f, %.1f, y:%1f,p:%1f): %8.5f %8.5f -> %8.5f %8.5f %8.5f -> %8.5f %8.5f\n",
		   mp->trans[0], mp->trans[1], mp->trans[2], mp->trans[3], mp->trans[4],
		   x_dest, y_dest, 
		   intersection[0], intersection[1], intersection[2],
		   *x_src, *y_src);
	*/

	return 1;
}


/** transfer a point from a camera centered at x1,y1,z1 into the camera at x2,y2,z2 */
int plane_transfer_from_camera( double x_dest, double y_dest, double * x_src, double * y_src, void * params)
{

	double plane_coeff[4];
	double p1[3];
	double p2[3];
	double intersection[3];

	// params: MakeParams

	// compute ray of sight for the current pixel in
	// the master panorama camera.
	// camera point
	p1[0] = mp->trans[0];
	p1[1] = mp->trans[1];
	p1[2] = mp->trans[2];

	// point on sphere (direction vector in camera coordinates)
	cart_erect(x_dest, y_dest, &p2[0], mp->distance);
	// add camera position to get point on ray
	p2[0] += p1[0];
	p2[1] += p1[1];
	p2[2] += p1[2];	


	// compute plane description
	cart_erect(mp->trans[3], -mp->trans[4],
			   &plane_coeff[0], 1.0);

	// plane_coeff[0..2] is both the normal and a point
	// on the plane.
	plane_coeff[3] = - plane_coeff[0]*plane_coeff[0]
		             - plane_coeff[1]*plane_coeff[1]
		             - plane_coeff[2]*plane_coeff[2];

	/*
	printf("Plane: y:%f p:%f coefficients: %f %f %f %f, ray direction: %f %f %f\n", 
	       mp->trans[3], mp->trans[4], plane_coeff[0], plane_coeff[1], plane_coeff[2], plane_coeff[3],
		   p2[0],p2[1],p2[2]);
	*/


	// compute intersection
	if (!line_plane_intersection(plane_coeff, p1, p2, &intersection[0])) {
		//printf("No intersection found, %f %f %f\n", p2[0], p2[1], p2[2]);
		return 0;
	}

	// the intersection vector is the vector of the ray of sight from
	// the master panorama camera.

	// transform into erect
	erect_cart(&intersection[0], x_src, y_src, mp->distance);

	/*
	printf("cam->plane->pano(%.1f, %.1f, %.1f, y:%1f,p:%1f): %8.5f %8.5f -> %8.5f %8.5f %8.5f -> %8.5f %8.5f\n",
		   mp->trans[0], mp->trans[1], mp->trans[2], mp->trans[3], mp->trans[4],
		   x_dest, y_dest, 
		   intersection[0], intersection[1], intersection[2],
		   *x_src, *y_src);
		   
	*/

	return 1;
}



/** convert from erect to biplane */
int biplane_erect		( double x_dest,double  y_dest, double* x_src, double* y_src, void* params )
{
	double x,offset;
	if (fabs(x_dest / mp->distance) > mp->pn->precomputedValue[0]+DEG_TO_RAD(89))
	{
		*x_src = 0;
		*y_src = 0;
		return 0;
	}
	if(x_dest<0)
	{
		x = x_dest + mp->pn->precomputedValue[0] * mp->distance;
		offset = -mp->pn->precomputedValue[1];
	}
	else
	{
		x = x_dest - mp->pn->precomputedValue[0] * mp->distance;
		offset = mp->pn->precomputedValue[1];
	}
	rect_erect(x,y_dest,x_src,y_src,&mp->distance);
	*x_src += offset;
	return 1;
}

/** convert from biplane to erect */
int erect_biplane		( double x_dest,double  y_dest, double* x_src, double* y_src, void* params )
{
	double x, offset;
	if(fabs(x_dest)>mp->pn->precomputedValue[1]+mp->distance*57)  // 57 = tan(89)
	{
		*x_src = 0;
		*y_src = 0;
		return 0;
	}
	if(x_dest<0)
	{
		x=x_dest + mp->pn->precomputedValue[1];
		offset = - mp->pn->precomputedValue[0];
	}
	else
	{
		x=x_dest - mp->pn->precomputedValue[1];
		offset = mp->pn->precomputedValue[0]; 
	} 
	erect_rect(x,y_dest,x_src,y_src,&mp->distance);
	*x_src += offset * mp->distance;
	return 1;
}


int biplane_distance ( double width, double b, void* params )
{
	if(mp->pn->formatParamCount==0)
	{
		mp->pn->formatParamCount = 1;
		mp->pn->formatParam[0] = 45;
	};
	mp->pn->formatParam[0]= max( min(mp->pn->formatParam[0], 179), 1);

	mp->pn->precomputedCount = 2;
	mp->pn->precomputedValue[0] = DEG_TO_RAD(mp->pn->formatParam[0]) / 2;  // angle in rad
	mp->distance = (double) width / (2.0 * (tan(mp->pn->precomputedValue[0])+tan(b/2.0 - mp->pn->precomputedValue[0])));
	mp->pn->precomputedValue[1]=mp->distance*tan(mp->pn->precomputedValue[0]);  // offset
	return 1;
}

int triplane_erect		( double x_dest,double  y_dest, double* x_src, double* y_src, void* params )
{
	double x,offset;
	if(fabs(x_dest / mp->distance)> mp->pn->precomputedValue[0] + DEG_TO_RAD(89))
	{
		*x_src = 0;
		*y_src = 0;
		return 0;
	};
	if(x_dest < -mp->pn->precomputedValue[0] / 2)
	{
		x=x_dest + mp->pn->precomputedValue[0] * mp->distance;
		offset = - mp->pn->precomputedValue[1];
	}
	else if (x_dest < mp->pn->precomputedValue[0] / 2)
	{
		x=x_dest;
		offset=0;
	}
	else
	{
		x=x_dest - mp->pn->precomputedValue[0] * mp->distance;
		offset = + mp->pn->precomputedValue[1];
	}
	rect_erect(x,y_dest,x_src,y_src,&mp->distance);
	*x_src += offset;
	return 1;
}

int erect_triplane		( double x_dest,double  y_dest, double* x_src, double* y_src, void* params )
{
	double x, offset;
	if(fabs(x_dest) > 2* mp->pn->precomputedValue[1] + 57 * mp->distance )
	{
		*x_src = 0;
		*y_src = 0;
		return 0;
	};
	if(x_dest < -mp->pn->precomputedValue[1])
	{
		x=x_dest + 2 * mp->pn->precomputedValue[1];
		offset = - mp->pn->precomputedValue[0];
	}
	else if (x_dest < mp->pn->precomputedValue[1])
	{
		x=x_dest;
		offset=0;
	}
	else
	{
		x=x_dest - 2 * mp->pn->precomputedValue[1];
		offset = + mp->pn->precomputedValue[0];
	}
	erect_rect(x,y_dest,x_src ,y_src,&mp->distance);
	*x_src += offset * mp->distance;
	return 1;
}

int triplane_distance ( double width, double b, void* params )
{
	if(mp->pn->formatParamCount==0)
	{
		mp->pn->formatParamCount = 1;
		mp->pn->formatParam[0] = 45;
	};
	mp->pn->formatParam[0] = max( min(mp->pn->formatParam[0], 120), 1);

	mp->pn->precomputedCount = 2;
	mp->pn->precomputedValue[0] = DEG_TO_RAD(mp->pn->formatParam[0]);  // angle in rad
	mp->distance = (double) width / (4.0 * tan(mp->pn->precomputedValue[0]/2.0) + 2 * tan(b/2.0 - mp->pn->precomputedValue[0]));
	mp->pn->precomputedValue[1]=mp->distance*tan(mp->pn->precomputedValue[0]/2.0);  // offset
	return 1;
}




int erect_sphere_tp( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam

	register double  theta,r,s;
	double	v[3];
#if 0	
	theta = sqrt( x_dest * x_dest + y_dest * y_dest ) / *((double*)params);
	phi   = atan2( y_dest , x_dest );
	
	v[1] = *((double*)params) * sin( theta ) * cos( phi );   //  x' -> y
	v[2] = *((double*)params) * sin( theta ) * sin( phi );	//  y' -> z
	v[0] = *((double*)params) * cos( theta );				//  z' -> x
	
	theta = atan( sqrt( v[0]*v[0] + v[1]*v[1] ) / v[2] ); //was atan2
	phi   = atan2( v[1], v[0] );

	*x_src = *((double*)params) * phi;
	if(theta > 0.0)
	{
		*y_src = *((double*)params) * (-theta + PI /2.0);
	}
	else
		*y_src = *((double*)params) * (-theta - PI /2.0);
#endif

	r = sqrt( x_dest * x_dest + y_dest * y_dest );
	theta = r / distanceparam;
	if(theta == 0.0)
		s = 1.0 / distanceparam;
	else
		s = sin( theta) / r;
	
	v[1] =  s * x_dest;   
	v[0] =  cos( theta );				
	

	*x_src = distanceparam * atan2( v[1], v[0] );
	*y_src = distanceparam * atan( s * y_dest /sqrt( v[0]*v[0] + v[1]*v[1] ) ); 
    return 1;
}


int mirror_sphere_cp( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam, double b

	register double rho, phi, theta;

	theta = sqrt( x_dest * x_dest + y_dest * y_dest ) / ((double*)params)[0];
	phi   = atan2( y_dest , x_dest );
	
	rho = ((double*)params)[1] * sin( theta / 2.0 );
	
	*x_src = - rho * cos( phi );
	*y_src = rho * sin( phi );
    return 1;
}


int mirror_erect( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam, double b, double b2

	register double phi, theta, rho;
	
	phi 	=  x_dest / ( ((double*)params)[0] * PI/2.0) ;
	theta 	=  - ( y_dest + ((double*)params)[2] ) / (((double*)params)[0] * PI/2.0)  ;
	
	rho = ((double*)params)[1] * sin( theta / 2.0 );
	
	*x_src = - rho * cos( phi );
	*y_src = rho * sin( phi );
    return 1;
}


int mirror_pano( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam, double b

	register double phi, theta, rho;
	
	
	phi 	= -x_dest / (((double*)params)[0] * PI/2.0) ;
	theta	= PI /2.0 + atan( y_dest / (((double*)params)[0] * PI/2.0) );

	rho = ((double*)params)[1] * sin( theta / 2.0 );
	
	*x_src = rho * cos( phi );
	*y_src = rho * sin( phi );
    return 1;
}


int sphere_cp_mirror( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
	// params: double distanceparam, double b

	register double phi, theta, rho;

	rho = sqrt( x_dest*x_dest + y_dest*y_dest );
	
	theta = 2 * asin( rho/((double*)params)[1] );
	phi   = atan2( y_dest , x_dest );

	*x_src = ((double*)params)[0] * theta * cos( phi );
	*y_src = ((double*)params)[0] * theta * sin( phi );
    return 1;
}

int sphere_tp_mirror( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
  register double c;
  register double normalizedX, normalizedY;
  register double azi;

  normalizedX = x_dest/ distanceparam;
  normalizedY = y_dest/ distanceparam;

  c = 2 * asin(hypot(normalizedX, normalizedY));
  azi = atan2( y_dest , x_dest );

  *x_src = distanceparam * c * cos(azi);
  *y_src = distanceparam * c * sin(azi);

  return 1;
}

int mirror_sphere_tp( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{

  register double c;
  register double normalizedX, normalizedY;
  register double azi;
  normalizedY = y_dest/ distanceparam;
  normalizedX = x_dest/ distanceparam;
  

  c = hypot(normalizedX, normalizedY);
  azi = atan2( y_dest , x_dest );

  *x_src = distanceparam * sin(c/2) * cos(azi);
  *y_src = distanceparam * sin(c/2) * sin(azi);

  return 1;
}

int sphere_tp_equisolid( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
  // params: double distance

  register double phi, theta, rho;

  rho = sqrt( x_dest*x_dest + y_dest*y_dest );
  
  theta = 2.0 * asin( rho/(2.0*((double*)params)[0]) );
  phi   = atan2( y_dest , x_dest );

  *x_src = ((double*)params)[0] * theta * cos( phi );
  *y_src = ((double*)params)[0] * theta * sin( phi );
  return 1;
}


int equisolid_sphere_tp( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
  // params: double distance

  register double rho, phi, theta;

  theta = sqrt( x_dest * x_dest + y_dest * y_dest ) / ((double*)params)[0];
  phi   = atan2( y_dest , x_dest );
  
  rho = 2.0 * ((double*)params)[0] * sin( theta / 2.0 );
  
  *x_src = rho * cos( phi );
  *y_src = rho * sin( phi );
  return 1;
}

int sphere_tp_orthographic( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
  // params: double distance

  register double phi, theta, rho;

  rho = sqrt( x_dest*x_dest + y_dest*y_dest );
  
  // orthographic projection is limited to fov of 180 deg
  if(rho>((double*)params)[0])
  {
      *x_src = 0;
      *y_src = 0;
      return 0;
  };
  theta = 1.0 * asin( rho/(1.0*((double*)params)[0]) );
  phi   = atan2( y_dest , x_dest );
  

  *x_src = ((double*)params)[0] * theta * cos( phi );
  *y_src = ((double*)params)[0] * theta * sin( phi );

  return 1;
}

int orthographic_sphere_tp( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
  // params: double distance

  register double rho, phi, theta;

  theta = sqrt( x_dest * x_dest + y_dest * y_dest ) / ((double*)params)[0];
  phi   = atan2( y_dest , x_dest );
  //orthographic projection is limited to fov of 180 deg
  if(fabs(theta)>HALF_PI)
  {
      *x_src=0;
      *y_src=0;
      return 0;
  };

  rho = 1.0 * ((double*)params)[0] * sin( theta / 1.0 );
  
  *x_src = rho * cos( phi );
  *y_src = rho * sin( phi );
  return 1;
}

// the Thoby projection is an empirically found projection for the Nikkor 10.5 lens
// rho = THOBY_K1_PARM * sin( theta  * THOBY_K2_PARM);

int sphere_tp_thoby( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
  // params: double distance

  register double phi, theta, rho;
#define SCALE (((double*)params)[0])

  rho = sqrt( x_dest*x_dest + y_dest*y_dest )/ SCALE;

  if(fabs(rho)>THOBY_K1_PARM)
  {
    *x_src=0;
    *y_src=0;
    return 0;
  };
  theta = asin( rho/THOBY_K1_PARM) / THOBY_K2_PARM;
  phi   = atan2( y_dest , x_dest );
  
  *x_src = SCALE * theta * cos( phi );
  *y_src = SCALE * theta * sin( phi );

#undef SCALE

  return 1;
}


int thoby_sphere_tp( double x_dest,double  y_dest, double* x_src, double* y_src, void* params)
{
  // params: double distance

  register double rho, phi, theta;

#define SCALE (((double*)params)[0])

  theta = sqrt( x_dest * x_dest + y_dest * y_dest ) / SCALE;
  phi   = atan2( y_dest , x_dest );
  
  rho = THOBY_K1_PARM * sin( theta  * THOBY_K2_PARM );
  
  *x_src = SCALE * rho * cos( phi );
  *y_src = SCALE * rho * sin( phi );

#undef SCALE
  return 1;
}


int shift_scale_rotate( double x_dest,double  y_dest, double* x_src, double* y_src, void* params){
	// params: double shift_x, shift_y, scale, cos_phi, sin_phi
	
	register double x = x_dest - ((double*)params)[0];
	register double y = y_dest - ((double*)params)[1];

	*x_src = (x * ((double*)params)[3] - y * ((double*)params)[4]) * ((double*)params)[2];
	*y_src = (x * ((double*)params)[4] + y * ((double*)params)[3]) * ((double*)params)[2];
    return 1;
}





// Correct radial luminance change using parabel

unsigned char radlum( unsigned char srcPixel, int xc, int yc, void *params )
{
	// params: second and zero order polynomial coeff
	register double result;

	result = (xc * xc + yc * yc) * ((double*)params)[0] + ((double*)params)[1];
	result = ((double)srcPixel) - result;

    // JMW 2003/08/25  randomize a little
    result = result * ( (1 + LUMINANCE_RANDOMIZE/2) - LUMINANCE_RANDOMIZE * rand() / (double)RAND_MAX );
    
	if(result < 0.0) return 0;
	if(result > 255.0) return 255;

	return( (unsigned char)(result+0.5) );
}

//Kekus 16 bit: 2003/Nov/18
//Correct radial luminance change using parabel (16-bit supported)
unsigned short radlum16( unsigned short srcPixel, int xc, int yc, void *params ) 
{
	// params: second and zero order polynomial coeff
	register double result;

	result = (xc * xc + yc * yc) * ((double*)params)[0] + ((double*)params)[1];
    result = ((double) srcPixel) - result*256;
    // JMW 2003/08/25  randomize a little to remove banding added by Kekus Digital 26 Aug 2003
	// JMW 2004/07/11 a power of two less randomizing for 16 bit
    result = result * ( (1 + LUMINANCE_RANDOMIZE * LUMINANCE_RANDOMIZE /2) - 
		LUMINANCE_RANDOMIZE * LUMINANCE_RANDOMIZE * rand() / (double)RAND_MAX );
    if(result > 65535.0) return 65535;
	if(result < 0.0) return 0;

	return( (unsigned short)(result+0.5) );
}
//Kekus.

// Get smallest positive (non-zero) root of polynomial with degree deg and
// (n+1) real coefficients p[i]. Return it, or 1000.0 if none exists or error occured
// Changed to only allow degree 3
#if 0
double smallestRoot( double *p )
{
	doublecomplex 		root[3], poly[4];
	doublereal 			radius[3], apoly[4], apolyr[4];
	logical 			myErr[3];
	double 				sRoot = 1000.0;
	doublereal 			theEps, theBig, theSmall;
	integer 			nitmax;
	integer 			iter;
	integer 			n,i;
	
	n 		= 3;

	
	for( i=0; i< n+1; i++)
	{
		poly[i].r = p[i];
		poly[i].i = 0.0;
	}
	
	theEps   = DBL_EPSILON;  		// machine precision 
	theSmall = DBL_MIN ; 			// smallest positive real*8          
	theBig   = DBL_MAX ; 			// largest real*8  

	nitmax 	= 100;

    polzeros_(&n, poly, &theEps, &theBig, &theSmall, &nitmax, root, radius, myErr, &iter, apoly, apolyr);

	for( i = 0; i < n; i++ )
	{
//		PrintError("No %d : Real %g, Imag %g, radius %g, myErr %ld", i, root[i].r, root[i].i, radius[i], myErr[i]);
		if( (root[i].r > 0.0) && (dabs( root[i].i ) <= radius[i]) && (root[i].r < sRoot) )
			sRoot = root[i].r;
	}

	return sRoot;
}
#endif



void cubeZero( double *a, int *n, double *root ) {
	if( a[3] == 0.0 ){ // second order polynomial
		squareZero( a, n, root );
	}else{
		double p = ((-1.0/3.0) * (a[2]/a[3]) * (a[2]/a[3]) + a[1]/a[3]) / 3.0;
		double q = ((2.0/27.0) * (a[2]/a[3]) * (a[2]/a[3]) * (a[2]/a[3]) - (1.0/3.0) * (a[2]/a[3]) * (a[1]/a[3]) + a[0]/a[3]) / 2.0;
		
		if( q*q + p*p*p >= 0.0 ){
			*n = 1;
			root[0] = cubeRoot(-q + sqrt(q*q + p*p*p)) + cubeRoot(-q - sqrt(q*q + p*p*p)) - a[2] / (3.0 * a[3]); 
		}else{
			double phi = acos( -q / sqrt(-p*p*p) );
			*n = 3;
			root[0] =  2.0 * sqrt(-p) * cos(phi/3.0) - a[2] / (3.0 * a[3]); 
			root[1] = -2.0 * sqrt(-p) * cos(phi/3.0 + PI/3.0) - a[2] / (3.0 * a[3]); 
			root[2] = -2.0 * sqrt(-p) * cos(phi/3.0 - PI/3.0) - a[2] / (3.0 * a[3]); 
		}
	}
	// PrintError("%lg, %lg, %lg, %lg root = %lg", a[3], a[2], a[1], a[0], root[0]);
}

void squareZero( double *a, int *n, double *root ){
	if( a[2] == 0.0 ){ // linear equation
		if( a[1] == 0.0 ){ // constant
			if( a[0] == 0.0 ){
				*n = 1; root[0] = 0.0;
			}else{
				*n = 0;
			}
		}else{
			*n = 1; root[0] = - a[0] / a[1];
		}
	}else{
		if( 4.0 * a[2] * a[0] > a[1] * a[1] ){
			*n = 0; 
		}else{
			*n = 2;
			root[0] = (- a[1] + sqrt( a[1] * a[1] - 4.0 * a[2] * a[0] )) / (2.0 * a[2]);
			root[1] = (- a[1] - sqrt( a[1] * a[1] - 4.0 * a[2] * a[0] )) / (2.0 * a[2]);
		}
	}

}

double cubeRoot( double x ){
	if( x == 0.0 )
		return 0.0;
	else if( x > 0.0 )
		return pow(x, 1.0/3.0);
	else
		return - pow(-x, 1.0/3.0);
}

double smallestRoot( double *p ){
	int n,i;
	double root[3], sroot = 1000.0;
	
	cubeZero( p, &n, root );
	
	for( i=0; i<n; i++){
		// PrintError("Root %d = %lg", i,root[i]);
		if(root[i] > 0.0 && root[i] < sroot)
			sroot = root[i];
	}
	
	// PrintError("Smallest Root  = %lg", sroot);
	return sroot;
}