int GPJ_get_datum_by_name(const char *name, struct gpj_datum *dstruct) { struct datum_list *list, *listhead; list = listhead = read_datum_table(); while (list != NULL) { if (G_strcasecmp(name, list->name) == 0) { dstruct->name = G_store(list->name); dstruct->longname = G_store(list->longname); dstruct->ellps = G_store(list->ellps); dstruct->dx = list->dx; dstruct->dy = list->dy; dstruct->dz = list->dz; free_datum_list(listhead); return 1; } list = list->next; } free_datum_list(listhead); return -1; }
int GPJ_osr_to_grass(struct Cell_head *cellhd, struct Key_Value **projinfo, struct Key_Value **projunits, OGRSpatialReferenceH hSRS, int datumtrans) { struct Key_Value *temp_projinfo; char *pszProj4 = NULL, *pszRemaining; char *pszProj = NULL; char *datum = NULL; struct gpj_datum dstruct; if (hSRS == NULL) goto default_to_xy; /* Set finder function for locating OGR csv co-ordinate system tables */ SetCSVFilenameHook(GPJ_set_csv_loc); /* Hopefully this doesn't do any harm if it wasn't in ESRI format * to start with... */ OSRMorphFromESRI(hSRS); /* -------------------------------------------------------------------- */ /* Set cellhd for well known coordinate systems. */ /* -------------------------------------------------------------------- */ if (!OSRIsGeographic(hSRS) && !OSRIsProjected(hSRS)) goto default_to_xy; if (cellhd) { int bNorth; if (OSRIsGeographic(hSRS)) { cellhd->proj = PROJECTION_LL; cellhd->zone = 0; } else if (OSRGetUTMZone(hSRS, &bNorth) != 0) { cellhd->proj = PROJECTION_UTM; cellhd->zone = OSRGetUTMZone(hSRS, &bNorth); if (!bNorth) cellhd->zone *= -1; } else { cellhd->proj = PROJECTION_OTHER; cellhd->zone = 0; } } /* -------------------------------------------------------------------- */ /* Get the coordinate system definition in PROJ.4 format. */ /* -------------------------------------------------------------------- */ if (OSRExportToProj4(hSRS, &pszProj4) != OGRERR_NONE) goto default_to_xy; /* -------------------------------------------------------------------- */ /* Parse the PROJ.4 string into key/value pairs. Do a bit of */ /* extra work to "GRASSify" the result. */ /* -------------------------------------------------------------------- */ temp_projinfo = G_create_key_value(); /* Create "local" copy of proj4 string so we can modify and free it * using GRASS functions */ pszRemaining = G_store(pszProj4); CPLFree(pszProj4); pszProj4 = pszRemaining; while ((pszRemaining = strstr(pszRemaining, "+")) != NULL) { char *pszToken, *pszValue; pszRemaining++; /* Advance pszRemaining to end of this token[=value] pair */ pszToken = pszRemaining; while (*pszRemaining != ' ' && *pszRemaining != '\0') pszRemaining++; if (*pszRemaining == ' ') { *pszRemaining = '\0'; pszRemaining++; } /* parse token, and value */ if (strstr(pszToken, "=") != NULL) { pszValue = strstr(pszToken, "="); *pszValue = '\0'; pszValue++; } else pszValue = "defined"; if (G_strcasecmp(pszToken, "proj") == 0) { /* The ll projection is known as longlat in PROJ.4 */ if (G_strcasecmp(pszValue, "longlat") == 0) pszValue = "ll"; pszProj = pszValue; continue; } /* Ellipsoid and datum handled separately below */ if (G_strcasecmp(pszToken, "ellps") == 0 || G_strcasecmp(pszToken, "a") == 0 || G_strcasecmp(pszToken, "b") == 0 || G_strcasecmp(pszToken, "es") == 0 || G_strcasecmp(pszToken, "rf") == 0 || G_strcasecmp(pszToken, "datum") == 0) continue; /* We will handle units separately */ if (G_strcasecmp(pszToken, "to_meter") == 0 || G_strcasecmp(pszToken, "units") == 0) continue; G_set_key_value(pszToken, pszValue, temp_projinfo); } *projinfo = G_create_key_value(); /* -------------------------------------------------------------------- */ /* Derive the user name for the projection. */ /* -------------------------------------------------------------------- */ if (pszProj) { char path[4095]; char name[80]; sprintf(path, "%s/etc/projections", G_gisbase()); if (G_lookup_key_value_from_file(path, pszProj, name, sizeof(name)) > 0) G_set_key_value("name", name, *projinfo); else G_set_key_value("name", pszProj, *projinfo); G_set_key_value("proj", pszProj, *projinfo); } else G_warning(_("No projection name! Projection parameters likely to be meaningless.")); /* -------------------------------------------------------------------- */ /* Find the GRASS datum name and choose parameters either */ /* interactively or not. */ /* -------------------------------------------------------------------- */ { const char *pszDatumNameConst = OSRGetAttrValue(hSRS, "DATUM", 0); struct datum_list *list, *listhead; char *dum1, *dum2, *pszDatumName; int paramspresent = GPJ__get_datum_params(temp_projinfo, &dum1, &dum2); if (pszDatumNameConst) { /* Need to make a new copy of the string so we don't mess * around with the memory inside the OGRSpatialReferenceH? */ pszDatumName = G_store(pszDatumNameConst); DatumNameMassage(&pszDatumName); list = listhead = read_datum_table(); while (list != NULL) { if (G_strcasecmp(pszDatumName, list->longname) == 0) { datum = G_store(list->name); break; } list = list->next; } free_datum_list(listhead); if (datum == NULL) { if (paramspresent < 2) /* Only give warning if no parameters present */ G_warning(_("Datum <%s> not recognised by GRASS and no parameters found"), pszDatumName); } else { G_set_key_value("datum", datum, *projinfo); if (paramspresent < 2) { /* If no datum parameters were imported from the OSR * object then we should use the set specified by datumtrans */ char *params, *chosenparams = NULL; int paramsets; paramsets = GPJ_get_default_datum_params_by_name(datum, ¶ms); if (paramsets < 0) G_warning(_("Datum <%s> apparently recognised by GRASS but no parameters found. " "You may want to look into this."), datum); else if (datumtrans > paramsets) { G_warning(_("Invalid transformation number %d; valid range is 1 to %d. " "Leaving datum transform parameters unspecified."), datumtrans, paramsets); datumtrans = 0; } if (paramsets > 0) { struct gpj_datum_transform_list *list, *old; list = GPJ_get_datum_transform_by_name(datum); if (list != NULL) { do { if (list->count == datumtrans) chosenparams = G_store(list->params); old = list; list = list->next; GPJ_free_datum_transform(old); } while (list != NULL); } } if (chosenparams != NULL) { char *paramkey, *paramvalue; paramkey = strtok(chosenparams, "="); paramvalue = chosenparams + strlen(paramkey) + 1; G_set_key_value(paramkey, paramvalue, *projinfo); G_free(chosenparams); } if (paramsets > 0) G_free(params); } } G_free(pszDatumName); } } /* -------------------------------------------------------------------- */ /* Determine an appropriate GRASS ellipsoid name if possible, or */ /* else just put a and es values into PROJ_INFO */ /* -------------------------------------------------------------------- */ if ((datum != NULL) && (GPJ_get_datum_by_name(datum, &dstruct) > 0)) { /* Use ellps name associated with datum */ G_set_key_value("ellps", dstruct.ellps, *projinfo); GPJ_free_datum(&dstruct); G_free(datum); } else { /* If we can't determine the ellipsoid from the datum, derive it * directly from "SPHEROID" parameters in WKT */ const char *pszSemiMajor = OSRGetAttrValue(hSRS, "SPHEROID", 1); const char *pszInvFlat = OSRGetAttrValue(hSRS, "SPHEROID", 2); if (pszSemiMajor != NULL && pszInvFlat != NULL) { char *ellps = NULL; struct ellps_list *list, *listhead; double a = atof(pszSemiMajor), invflat = atof(pszInvFlat), flat; double es; /* Allow for incorrect WKT describing a sphere where InvFlat * is given as 0 rather than inf */ if (invflat > 0) flat = 1 / invflat; else flat = 0; es = flat * (2.0 - flat); list = listhead = read_ellipsoid_table(0); while (list != NULL) { /* Try and match a and es against GRASS defined ellipsoids; * accept first one that matches. These numbers were found * by trial and error and could be fine-tuned, or possibly * a direct comparison of IEEE floating point values used. */ if ((a == list->a || fabs(a - list->a) < 0.1 || fabs(1 - a / list->a) < 0.0000001) && ((es == 0 && list->es == 0) || /* Special case for sphere */ (invflat == list->rf || fabs(invflat - list->rf) < 0.0000001))) { ellps = G_store(list->name); break; } list = list->next; } if (listhead != NULL) free_ellps_list(listhead); if (ellps == NULL) { /* If we weren't able to find a matching ellps name, set * a and es values directly from WKT-derived data */ char es_str[100]; G_set_key_value("a", (char *)pszSemiMajor, *projinfo); sprintf(es_str, "%.16g", es); G_set_key_value("es", es_str, *projinfo); } else { /* else specify the GRASS ellps name for readability */ G_set_key_value("ellps", ellps, *projinfo); G_free(ellps); } } } /* -------------------------------------------------------------------- */ /* Finally append the detailed projection parameters to the end */ /* -------------------------------------------------------------------- */ { int i; for (i = 0; i < temp_projinfo->nitems; i++) G_set_key_value(temp_projinfo->key[i], temp_projinfo->value[i], *projinfo); G_free_key_value(temp_projinfo); } G_free(pszProj4); /* -------------------------------------------------------------------- */ /* Set the linear units. */ /* -------------------------------------------------------------------- */ *projunits = G_create_key_value(); if (OSRIsGeographic(hSRS)) { /* We assume degrees ... someday we will be wrong! */ G_set_key_value("unit", "degree", *projunits); G_set_key_value("units", "degrees", *projunits); G_set_key_value("meters", "1.0", *projunits); } else { char szFormatBuf[256]; char *pszUnitsName = NULL; double dfToMeters; char *pszUnitsPlural, *pszStringEnd; dfToMeters = OSRGetLinearUnits(hSRS, &pszUnitsName); /* Workaround for the most obvious case when unit name is unknown */ if ((G_strcasecmp(pszUnitsName, "unknown") == 0) && (dfToMeters == 1.)) G_asprintf(&pszUnitsName, "meter"); G_set_key_value("unit", pszUnitsName, *projunits); /* Attempt at plural formation (WKT format doesn't store plural * form of unit name) */ pszUnitsPlural = G_malloc(strlen(pszUnitsName) + 3); strcpy(pszUnitsPlural, pszUnitsName); pszStringEnd = pszUnitsPlural + strlen(pszUnitsPlural) - 4; if (G_strcasecmp(pszStringEnd, "foot") == 0) { /* Special case for foot - change two o's to e's */ pszStringEnd[1] = 'e'; pszStringEnd[2] = 'e'; } else if (G_strcasecmp(pszStringEnd, "inch") == 0) { /* Special case for inch - add es */ pszStringEnd[4] = 'e'; pszStringEnd[5] = 's'; pszStringEnd[6] = '\0'; } else { /* For anything else add an s at the end */ pszStringEnd[4] = 's'; pszStringEnd[5] = '\0'; } G_set_key_value("units", pszUnitsPlural, *projunits); G_free(pszUnitsPlural); sprintf(szFormatBuf, "%.16g", dfToMeters); G_set_key_value("meters", szFormatBuf, *projunits); } return 2; /* -------------------------------------------------------------------- */ /* Fallback to returning an ungeoreferenced definition. */ /* -------------------------------------------------------------------- */ default_to_xy: if (cellhd != NULL) { cellhd->proj = PROJECTION_XY; cellhd->zone = 0; } *projinfo = NULL; *projunits = NULL; return 1; }