Function GMT_gmtsimplify

src/gmtsimplify.c:279–414

#define Return(code) {Free_Ctrl (GMT, Ctrl); gmt_end_module (GMT, GMT_cpy); bailout (code);}

EXTERN_MSC int GMT_gmtsimplify (void *V_API, int mode, void *args) {
	int error;
	unsigned int smode = GMT_NO_STRINGS;
	bool geo, poly, skip;
	uint64_t tbl, col, row, seg_in, seg_out, np_out, ns_in = 0, ns_out = 0, n_in_tbl, *index = NULL;
	uint64_t dim_out[4] = {1, 0, 0, 0}, n_saved;

	double tolerance;

	struct GMT_DATASET *D[2] = {NULL, NULL};
	struct GMT_DATASEGMENT *S[2] = {NULL, NULL};
	struct GMTSIMPLIFY_CTRL *Ctrl = NULL;
	struct GMT_CTRL *GMT = NULL, *GMT_cpy = NULL;
	struct GMT_OPTION *options = NULL;
	struct GMTAPI_CTRL *API = gmt_get_api_ptr (V_API);	/* Cast from void to GMTAPI_CTRL pointer */

	/*----------------------- Standard module initialization and parsing ----------------------*/

	if (API == NULL) return (GMT_NOT_A_SESSION);
	if (mode == GMT_MODULE_PURPOSE) return (usage (API, GMT_MODULE_PURPOSE));	/* Return the purpose of program */
	options = GMT_Create_Options (API, mode, args);	if (API->error) return (API->error);	/* Set or get option list */

	if ((error = gmt_report_usage (API, options, 0, usage)) != GMT_NOERROR) bailout (error);	/* Give usage if requested */

	/* Parse the command-line arguments */

	if ((GMT = gmt_init_module (API, THIS_MODULE_LIB, THIS_MODULE_CLASSIC_NAME, THIS_MODULE_KEYS, THIS_MODULE_NEEDS, module_kw, &options, &GMT_cpy)) == NULL) bailout (API->error); /* Save current state */
	if (GMT_Parse_Common (API, THIS_MODULE_OPTIONS, options)) Return (API->error);
	Ctrl = New_Ctrl (GMT);	/* Allocate and initialize a new control structure */
	if ((error = parse (GMT, Ctrl, options)) != 0) Return (error);

	/*---------------------------- This is the gmtsimplify main code ----------------------------*/

	GMT_Report (API, GMT_MSG_INFORMATION, "Processing input table data\n");
	if (Ctrl->T.mode > 1) {
		GMT_Report (API, GMT_MSG_INFORMATION, "gmtsimplify only implemented using Flat-Earth calculations.\n");
		Ctrl->T.mode = 1;	/* Limited to Flat Earth calculations for now */
	}

	/* Now we are ready to take on some input values */
	/* Allocate memory and read in all the files; each file can have many lines */

	/* We read as lines even though some/all segments could be polygons. */
	if (GMT_Init_IO (API, GMT_IS_DATASET, GMT_IS_LINE, GMT_IN, GMT_ADD_DEFAULT, 0, options) != GMT_NOERROR) {	/* Establishes data input */
		Return (API->error);
	}
	if ((D[GMT_IN] = GMT_Read_Data (API, GMT_IS_DATASET, GMT_IS_FILE, 0, GMT_READ_NORMAL, NULL, NULL, NULL)) == NULL) {
		Return (API->error);
	}
	if (D[GMT_IN]->n_columns < 2) {
		GMT_Report (API, GMT_MSG_ERROR, "Input data have %d column(s) but at least 2 are needed\n", (int)D[GMT_IN]->n_columns);
		Return (GMT_DIM_TOO_SMALL);
	}
	geo = gmt_M_is_geographic (GMT, GMT_IN);					/* true for lon/lat coordinates */
	if (!geo && strchr (GMT_LEN_UNITS, (int)Ctrl->T.unit)) geo = true;	/* Used units but did not set -fg; implicitly set -fg via geo */

	if (gmt_init_distaz (GMT, Ctrl->T.unit, Ctrl->T.mode, GMT_MAP_DIST) == GMT_NOT_A_VALID_TYPE)	/* Initialize distance scalings according to unit selected */
		Return (GMT_NOT_A_VALID_TYPE);