diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/projections/healpix.cpp | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/src/projections/healpix.cpp b/src/projections/healpix.cpp index 515f4f6f..4acb4f69 100644 --- a/src/projections/healpix.cpp +++ b/src/projections/healpix.cpp @@ -36,7 +36,7 @@ #include "proj.h" #include "proj_internal.h" -PROJ_HEAD(healpix, "HEAPJ_LPix") "\n\tSph&Ell"; +PROJ_HEAD(healpix, "HEAPJ_LPix") "\n\tSph&Ell\n\trot_xy="; PROJ_HEAD(rhealpix, "rHEAPJ_LPix") "\n\tSph&Ell\n\tnorth_square= south_square="; /* Matrix for counterclockwise rotation by pi/2: */ @@ -56,6 +56,7 @@ namespace { // anonymous namespace struct pj_opaque { int north_square; int south_square; + double rot_xy; double qp; double *apa; }; @@ -78,6 +79,12 @@ static double sign (double v) { return v > 0 ? 1 : (v < 0 ? -1 : 0); } +static PJ_XY rotate(PJ_XY p, double angle) { + PJ_XY result; + result.x = p.x * cos(angle) - p.y * sin(angle); + result.y = p.y * cos(angle) + p.x * sin(angle); + return result; +} /** * Return the index of the matrix in ROT. @@ -178,7 +185,8 @@ static int in_image(double x, double y, int proj, int north_square, {-M_FORTPI, -M_HALFPI - EPS}, {-M_HALFPI, -M_FORTPI - EPS}, {-3*M_FORTPI, -M_HALFPI - EPS}, - {-M_PI - EPS, -M_FORTPI} + {-M_PI - EPS, -M_FORTPI}, + {-M_PI - EPS, M_FORTPI} }; return pnpoly((int)sizeof(healpixVertsJit)/ sizeof(healpixVertsJit[0]), healpixVertsJit, x, y); @@ -513,17 +521,22 @@ static PJ_XY combine_caps(double x, double y, int north_square, int south_square static PJ_XY s_healpix_forward(PJ_LP lp, PJ *P) { /* sphere */ (void) P; - return healpix_sphere(lp); + struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque); + return rotate(healpix_sphere(lp), -Q->rot_xy); } static PJ_XY e_healpix_forward(PJ_LP lp, PJ *P) { /* ellipsoid */ lp.phi = auth_lat(P, lp.phi, 0); - return healpix_sphere(lp); + struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque); + return rotate(healpix_sphere(lp), -Q->rot_xy); } static PJ_LP s_healpix_inverse(PJ_XY xy, PJ *P) { /* sphere */ + struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque); + xy = rotate(xy, Q->rot_xy); + /* Check whether (x, y) lies in the HEAPJ_LPix image */ if (in_image(xy.x, xy.y, 0, 0, 0) == 0) { PJ_LP lp; @@ -538,6 +551,8 @@ static PJ_LP s_healpix_inverse(PJ_XY xy, PJ *P) { /* sphere */ static PJ_LP e_healpix_inverse(PJ_XY xy, PJ *P) { /* ellipsoid */ PJ_LP lp = {0.0,0.0}; + struct pj_opaque *Q = static_cast<struct pj_opaque*>(P->opaque); + xy = rotate(xy, Q->rot_xy); /* Check whether (x, y) lies in the HEAPJ_LPix image. */ if (in_image(xy.x, xy.y, 0, 0, 0) == 0) { @@ -622,6 +637,9 @@ PJ *PROJECTION(healpix) { P->opaque = Q; P->destructor = destructor; + double angle = pj_param(P->ctx, P->params,"drot_xy").f; + Q->rot_xy = PJ_TORAD(angle); + if (P->es != 0.0) { Q->apa = pj_authset(P->es); /* For auth_lat(). */ if (nullptr==Q->apa) |