diff options
Diffstat (limited to 'src/pj_inv.cpp')
| -rw-r--r-- | src/pj_inv.cpp | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/src/pj_inv.cpp b/src/pj_inv.cpp new file mode 100644 index 00000000..aaa8fea9 --- /dev/null +++ b/src/pj_inv.cpp @@ -0,0 +1,238 @@ +/****************************************************************************** + * Project: PROJ.4 + * Purpose: Inverse operation invocation + * Author: Thomas Knudsen, thokn@sdfe.dk, 2018-01-02 + * Based on material from Gerald Evenden (original pj_inv) + * and Piyush Agram (original pj_inv3d) + * + ****************************************************************************** + * Copyright (c) 2000, Frank Warmerdam + * Copyright (c) 2018, Thomas Knudsen / SDFE + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + *****************************************************************************/ +#include <errno.h> +#include <math.h> + +#include "proj_internal.h" +#include "proj_math.h" +#include "projects.h" + +#define INPUT_UNITS P->right +#define OUTPUT_UNITS P->left + +static PJ_COORD inv_prepare (PJ *P, PJ_COORD coo) { + if (coo.v[0] == HUGE_VAL || coo.v[1] == HUGE_VAL || coo.v[2] == HUGE_VAL) { + proj_errno_set (P, PJD_ERR_INVALID_X_OR_Y); + return proj_coord_error (); + } + + /* The helmert datum shift will choke unless it gets a sensible 4D coordinate */ + if (HUGE_VAL==coo.v[2] && P->helmert) coo.v[2] = 0.0; + if (HUGE_VAL==coo.v[3] && P->helmert) coo.v[3] = 0.0; + + if (P->axisswap) + coo = proj_trans (P->axisswap, PJ_INV, coo); + + /* Handle remaining possible input types */ + switch (INPUT_UNITS) { + case PJ_IO_UNITS_WHATEVER: + return coo; + + /* de-scale and de-offset */ + case PJ_IO_UNITS_CARTESIAN: + coo.xyz.x *= P->to_meter; + coo.xyz.y *= P->to_meter; + coo.xyz.z *= P->to_meter; + if (P->is_geocent) { + coo = proj_trans (P->cart, PJ_INV, coo); + } + + return coo; + + case PJ_IO_UNITS_PROJECTED: + case PJ_IO_UNITS_CLASSIC: + coo.xyz.x = P->to_meter * coo.xyz.x - P->x0; + coo.xyz.y = P->to_meter * coo.xyz.y - P->y0; + coo.xyz.z = P->vto_meter * coo.xyz.z - P->z0; + if (INPUT_UNITS==PJ_IO_UNITS_PROJECTED) + return coo; + + /* Classic proj.4 functions expect plane coordinates in units of the semimajor axis */ + /* Multiplying by ra, rather than dividing by a because the CalCOFI projection */ + /* stomps on a and hence (apparently) depends on this to roundtrip correctly */ + /* (CalCOFI avoids further scaling by stomping - but a better solution is possible) */ + coo.xyz.x *= P->ra; + coo.xyz.y *= P->ra; + return coo; + + case PJ_IO_UNITS_ANGULAR: + coo.lpz.z = P->vto_meter * coo.lpz.z - P->z0; + break; + } + + /* Should not happen, so we could return pj_coord_err here */ + return coo; +} + + + +static PJ_COORD inv_finalize (PJ *P, PJ_COORD coo) { + if (coo.xyz.x == HUGE_VAL) { + proj_errno_set (P, PJD_ERR_INVALID_X_OR_Y); + return proj_coord_error (); + } + + if (OUTPUT_UNITS==PJ_IO_UNITS_ANGULAR) { + + /* Distance from central meridian, taking system zero meridian into account */ + coo.lp.lam = coo.lp.lam + P->from_greenwich + P->lam0; + + /* adjust longitude to central meridian */ + if (0==P->over) + coo.lpz.lam = adjlon(coo.lpz.lam); + + if (P->vgridshift) + coo = proj_trans (P->vgridshift, PJ_INV, coo); /* Go geometric from orthometric */ + if (coo.lp.lam==HUGE_VAL) + return coo; + if (P->hgridshift) + coo = proj_trans (P->hgridshift, PJ_FWD, coo); + else if (P->helmert || (P->cart_wgs84 != 0 && P->cart != 0)) { + coo = proj_trans (P->cart, PJ_FWD, coo); /* Go cartesian in local frame */ + if( P->helmert ) + coo = proj_trans (P->helmert, PJ_FWD, coo); /* Step into WGS84 */ + coo = proj_trans (P->cart_wgs84, PJ_INV, coo); /* Go back to angular using WGS84 ellps */ + } + if (coo.lp.lam==HUGE_VAL) + return coo; + + /* If input latitude was geocentrical, convert back to geocentrical */ + if (P->geoc) + coo = pj_geocentric_latitude (P, PJ_FWD, coo); + } + + return coo; +} + + +static PJ_COORD error_or_coord(PJ *P, PJ_COORD coord, int last_errno) { + if (proj_errno(P)) + return proj_coord_error(); + + proj_errno_restore(P, last_errno); + return coord; +} + + +LP pj_inv(XY xy, PJ *P) { + int last_errno; + PJ_COORD coo = {{0,0,0,0}}; + coo.xy = xy; + + last_errno = proj_errno_reset(P); + + if (!P->skip_inv_prepare) + coo = inv_prepare (P, coo); + if (HUGE_VAL==coo.v[0]) + return proj_coord_error ().lp; + + /* Do the transformation, using the lowest dimensional transformer available */ + if (P->inv) + coo.lp = P->inv(coo.xy, P); + else if (P->inv3d) + coo.lpz = P->inv3d (coo.xyz, P); + else if (P->inv4d) + coo = P->inv4d (coo, P); + else { + proj_errno_set (P, EINVAL); + return proj_coord_error ().lp; + } + if (HUGE_VAL==coo.v[0]) + return proj_coord_error ().lp; + + if (!P->skip_inv_finalize) + coo = inv_finalize (P, coo); + + return error_or_coord(P, coo, last_errno).lp; +} + + + +LPZ pj_inv3d (XYZ xyz, PJ *P) { + int last_errno; + PJ_COORD coo = {{0,0,0,0}}; + coo.xyz = xyz; + + last_errno = proj_errno_reset(P); + + if (!P->skip_inv_prepare) + coo = inv_prepare (P, coo); + if (HUGE_VAL==coo.v[0]) + return proj_coord_error ().lpz; + + /* Do the transformation, using the lowest dimensional transformer feasible */ + if (P->inv3d) + coo.lpz = P->inv3d (coo.xyz, P); + else if (P->inv4d) + coo = P->inv4d (coo, P); + else if (P->inv) + coo.lp = P->inv (coo.xy, P); + else { + proj_errno_set (P, EINVAL); + return proj_coord_error ().lpz; + } + if (HUGE_VAL==coo.v[0]) + return proj_coord_error ().lpz; + + if (!P->skip_inv_finalize) + coo = inv_finalize (P, coo); + + return error_or_coord(P, coo, last_errno).lpz; +} + + + +PJ_COORD pj_inv4d (PJ_COORD coo, PJ *P) { + int last_errno = proj_errno_reset(P); + + if (!P->skip_inv_prepare) + coo = inv_prepare (P, coo); + if (HUGE_VAL==coo.v[0]) + return proj_coord_error (); + + /* Call the highest dimensional converter available */ + if (P->inv4d) + coo = P->inv4d (coo, P); + else if (P->inv3d) + coo.lpz = P->inv3d (coo.xyz, P); + else if (P->inv) + coo.lp = P->inv (coo.xy, P); + else { + proj_errno_set (P, EINVAL); + return proj_coord_error (); + } + if (HUGE_VAL==coo.v[0]) + return proj_coord_error (); + + if (!P->skip_inv_finalize) + coo = inv_finalize (P, coo); + + return error_or_coord(P, coo, last_errno); +} |
