Function gmtapi_export_grid

src/gmt_api.c:5764–5975

! Writes out a single grid to destination */

/*! Writes out a single grid to destination */
GMT_LOCAL int gmtapi_export_grid (struct GMTAPI_CTRL *API, int object_ID, unsigned int mode, struct GMT_GRID *G_obj) {
	int item, error;
	bool done = true, row_by_row;
	unsigned int method;
	openmp_int row, col, i0, i1, j0, j1;
	uint64_t ij, ijp, ij_orig;
	size_t size;
	double dx, dy;
	p_func_uint64_t GMT_2D_to_index = NULL;
	GMT_putfunction api_put_val = NULL;
	struct GMTAPI_DATA_OBJECT *S_obj = NULL;
	struct GMT_GRID *G_copy = NULL;
	struct GMT_MATRIX *M_obj = NULL;
	struct GMT_MATRIX_HIDDEN *MH = NULL;
	struct GMT_GRID_HIDDEN *GH = gmt_get_G_hidden (G_obj), *GH2 = NULL;
	struct GMT_CTRL *GMT = API->GMT;

	GMT_Report (API, GMT_MSG_DEBUG, "gmtapi_export_grid: Passed ID = %d and mode = %d\n", object_ID, mode);

	if (object_ID == GMT_NOTSET) return (gmtlib_report_error (API, GMT_OUTPUT_NOT_SET));
	if (G_obj->data == NULL && !(mode & GMT_CONTAINER_ONLY)) return (gmtlib_report_error (API, GMT_PTR_IS_NULL));
	if ((item = gmtlib_validate_id (API, GMT_IS_GRID, object_ID, GMT_OUT, GMT_NOTSET)) == GMT_NOTSET) return (gmtlib_report_error (API, API->error));

	S_obj = API->object[item];	/* The current object whose data we will export */
	if (S_obj->status != GMT_IS_UNUSED && !(mode & GMT_IO_RESET))
		return (gmtlib_report_error (API, GMT_WRITTEN_ONCE));	/* Only allow writing of a data set once, unless overridden by mode */
	if (mode & GMT_IO_RESET) mode -= GMT_IO_RESET;
	row_by_row = ((mode & GMT_GRID_ROW_BY_ROW) || (mode & GMT_GRID_ROW_BY_ROW_MANUAL));
	if (row_by_row && S_obj->method != GMT_IS_FILE) {
		GMT_Report (API, GMT_MSG_ERROR, "Can only use method GMT_IS_FILE when row-by-row writing of grid is selected\n");
		return (gmtlib_report_error (API, GMT_NOT_A_VALID_METHOD));
	}
	if (S_obj->region) {	/* See if this is really a subset or just the same region as the grid */
		if (G_obj->header->wesn[XLO] == S_obj->wesn[XLO] && G_obj->header->wesn[XHI] == S_obj->wesn[XHI] && G_obj->header->wesn[YLO] == S_obj->wesn[YLO] && G_obj->header->wesn[YHI] == S_obj->wesn[YHI]) S_obj->region = false;
	}
	if (mode & GMT_DATA_IS_GEO)	/* From API to tell grid is geographic */
		gmt_set_geographic (GMT, GMT_OUT);
	else {
		/* Some grids are geographic and others are Cartesian, but the user may wish to flip this fact
		 * via -f. Here we catch such deviousness and set the desired output geo/cart mode imposed by -f. */
		if (GMT->common.f.is_geo[GMT_OUT])
			gmt_set_geographic (GMT, GMT_OUT);
		else if (GMT->common.f.is_cart[GMT_OUT])
			gmt_set_cartesian (GMT, GMT_OUT);
	}

	gmtlib_grd_set_units (GMT, G_obj->header);	/* Ensure unit strings are set, regardless of destination */
	method = gmtapi_set_method (S_obj);	/* Get the actual method to use since may be MATRIX or VECTOR masquerading as GRID */
	switch (method) {
		case GMT_IS_FILE:	/* Name of a grid file on disk */
			if (mode & GMT_CONTAINER_ONLY) {	/* Update header structure only */
				GMT_Report (API, GMT_MSG_INFORMATION, "Updating grid header for file %s\n", S_obj->filename);
				if (row_by_row) {	/* Special row-by-row processing mode */
					char w_mode = (mode & GMT_GRID_NO_HEADER) ? 'W' : 'w';
					/* Since we may get here twice (initial write; later update) we only allocate extra if NULL */
					if (GH->extra == NULL) GH->extra = gmt_M_memory (GMT, NULL, 1, struct GMT_GRID_ROWBYROW);
					if (GH->extra == NULL) {
						return (gmtlib_report_error (API, GMT_MEMORY_ERROR));