Save any default CPT for remote datasets in hidden grid header

src/gmt_api.c

@@ -8198,11 +8198,12 @@ void * GMT_Create_Session (const char *session, unsigned int pad, unsigned int m
 
 	if ((API = calloc (1, sizeof (struct GMTAPI_CTRL))) == NULL) return_null (NULL, GMT_MEMORY_ERROR);	/* Failed to allocate the structure */
 	API->verbose = (mode >> 16);	/* Pick up any -V settings from gmt.c */
-	API->pad = pad;		/* Preserve the default pad value for this session */
+	API->remote_id = GMT_NOTSET;     /* Not read a remote grid yet */
+	API->pad = pad;     /* Preserve the default pad value for this session */
 	API->print_func = (print_func == NULL) ? gmtapi_print_func : print_func;	/* Pointer to the print function to use in GMT_Message|Report */
 	API->do_not_exit = mode & GMT_SESSION_NOEXIT;	/* Deprecated, we no longer call exit anywhere in the API (gmt_api.c) */
-    API->external = (mode & GMT_SESSION_EXTERNAL) ? 1 : 0;  /* if false|0 then we don't list read and write as modules */
-    if (API->external && mode & GMT_SESSION_NOGDALCLOSE) API->external = 2;  /* Avoid calling GDALDestroyDriverManager */
+	API->external = (mode & GMT_SESSION_EXTERNAL) ? 1 : 0;  /* if false|0 then we don't list read and write as modules */
+	if (API->external && mode & GMT_SESSION_NOGDALCLOSE) API->external = 2;  /* Avoid calling GDALDestroyDriverManager */
 	API->shape = (mode & GMT_SESSION_COLMAJOR) ? GMT_IS_COL_FORMAT : GMT_IS_ROW_FORMAT;		/* if set then we must use column-major format [row-major] */
 	API->runmode = mode & GMT_SESSION_RUNMODE;		/* If nonzero we set up modern GMT run-mode, else classic */
 	API->no_history = mode & GMT_SESSION_NOHISTORY;		/* If nonzero we disable the gmt.history mechanism (shorthands) entirely */

src/gmt_dev.h

@@ -129,13 +129,13 @@ extern "C" {
 #include "gmt_common_math.h" /* Shared math functions */
 #include "gmt.h"             /* All GMT high-level API */
 #include "gmt_private.h"     /* API declaration needed by libraries */
+#include "gmt_constants.h"   /* All basic constant definitions */
 #include "gmt_hidden.h"      /* Hidden bookkeeping structure for API containers */
 
 struct GMT_CTRL; /* forward declaration of GMT_CTRL */
 
 #include "gmt_notposix.h"       /* Non-POSIX extensions */
 
-#include "gmt_constants.h"      /* All basic constant definitions */
 #include "gmt_modern.h"         /* Modern mode constant definitions */
 #include "gmt_macros.h"         /* All basic macros definitions */
 #include "gmt_dimensions.h"     /* Constant definitions created by configure */

src/gmt_grdio.c

@@ -756,6 +756,7 @@ void gmt_copy_gridheader (struct GMT_CTRL *GMT, struct GMT_GRID_HEADER *to, stru
 	if (Hto->title) gmt_M_str_free (Hto->title);			/* Since we will duplicate via from */
 	if (Hto->command) gmt_M_str_free (Hto->command);			/* Since we will duplicate via from */
 	if (Hto->remark) gmt_M_str_free (Hto->remark);			/* Since we will duplicate via from */
+	if (Hto->cpt) gmt_M_str_free (Hto->cpt);				/* Since we will duplicate via from */
 	gmt_M_memcpy (to, from, 1, struct GMT_GRID_HEADER);		/* Copies full contents but also duplicates the hidden address */
 	to->hidden = Hto;	/* Restore the original hidden address in to */
 	gmt_M_memcpy (to->hidden, from->hidden, 1, struct GMT_GRID_HEADER_HIDDEN);	/* Copies full contents of hidden area */
@@ -766,6 +767,7 @@ void gmt_copy_gridheader (struct GMT_CTRL *GMT, struct GMT_GRID_HEADER *to, stru
 	if (Hfrom->title) Hto->title = strdup (Hfrom->title);
 	if (Hfrom->command) Hto->command = strdup (Hfrom->command);
 	if (Hfrom->remark) Hto->remark = strdup (Hfrom->remark);
+	if (Hfrom->cpt) Hto->cpt = strdup (Hfrom->cpt);
 }
 
 /*! gmt_grd_is_global returns true for a geographic grid with exactly 360-degree range (with or without repeating column) */
@@ -2112,6 +2114,7 @@ void gmt_grd_init (struct GMT_CTRL *GMT, struct GMT_GRID_HEADER *header, struct
 		if (HH->command) gmt_M_str_free (HH->command);	/* Free previous string */
 		if (HH->title)   gmt_M_str_free (HH->title);	/* Free previous string */
 		if (HH->remark)  gmt_M_str_free (HH->remark);	/* Free previous string */
+		if (HH->cpt)     gmt_M_str_free (HH->cpt);		/* Free previous string */
 		gmt_M_memcpy (mem, header->mem_layout, 4, char);
 		gmt_M_memset (header, 1, struct GMT_GRID_HEADER);
 		HH->index_function = ptr;
@@ -2932,6 +2935,7 @@ void gmt_free_header (struct GMT_CTRL *GMT, struct GMT_GRID_HEADER **header) {
 	if (HH->title)   gmt_M_str_free (HH->title);
 	if (HH->command) gmt_M_str_free (HH->command);
 	if (HH->remark)  gmt_M_str_free (HH->remark);
+	if (HH->cpt)  gmt_M_str_free (HH->cpt);
 	gmt_M_free (GMT, h->hidden);
 	gmt_M_free (GMT, *header);
 }

src/gmt_hidden.h

@@ -159,6 +159,7 @@ struct GMT_GRID_HEADER_HIDDEN {
 	char name[GMT_GRID_NAME_LEN256]; /* Actual name of the file after any ?<varname> and =<stuff> has been removed */
 	char varname[GMT_GRID_VARNAME_LEN80];/* NetCDF: variable name */
 	char *title;					 /* Title string not limited to GMT_GRID_TITLE_LEN80 characters */
+	char *cpt; 						 /* Name of default CPT for a remote grid subset written via grdcut */
 	char *command;					 /* Command/history string not limited to GMT_GRID_TITLE_LEN80 characters */
 	char *remark;					 /* Remark/description string not limited to GMT_GRID_REMARK_LEN160 characters */
 	int row_order;                   /* NetCDF: k_nc_start_south if S->N, k_nc_start_north if N->S */

src/gmt_init.c

@@ -15561,6 +15561,7 @@ struct GMT_CTRL *gmt_init_module (struct GMTAPI_CTRL *API, const char *lib_name,
 					wesn[YHI] = ceil  ((wesn[YHI] / d_inc) - GMT_CONV8_LIMIT) * d_inc;
 					gmt_M_memcpy (API->tile_wesn, wesn, 4, double);	/* Retain this knowledge in case it was obtained via map_setup for an oblique area */
 					API->got_remote_wesn = true;	/* In case we need to use this subset when reading a grid or image */
+					API->remote_id = k_data2;
 				}
 				if (dry_run)
 					goto dry_run;

src/gmt_io.c

@@ -4742,8 +4742,9 @@ int gmtlib_nc_get_att_text (struct GMT_CTRL *GMT, int ncid, int varid, char *nam
 /*! . */
 int gmtlib_nc_get_att_vtext (struct GMT_CTRL *GMT, int ncid, int varid, char *name, struct GMT_GRID_HEADER *h, char *text, size_t textlen) {
 	/* Similar to gmtlib_nc_get_att_text and used for title, history, and remark which, if longer than what can fit in header
-	 * are stored as allocated strings in the struct GMT_GRID_HEADER_HIDDEN structure.
+	 * are stored as allocated strings in the struct GMT_GRID_HEADER_HIDDEN structure.  We also place cpt in the hidden struct if found.
 	 * ncid, varid, name, text	: as in nc_get_att_text
+	 * If text is NULL then we do not access it
 	 * h  				: the pointer to the grid header structure
 	 * textlen			: maximum number of characters to copy to string text
 	 */
@@ -4752,9 +4753,13 @@ int gmtlib_nc_get_att_vtext (struct GMT_CTRL *GMT, int ncid, int varid, char *na
 	size_t attlen, trunclen;
 	char *att = NULL;
 
+	if (name == NULL) {
+		GMT_Report (GMT->parent, GMT_MSG_ERROR, "Attribute name passed to gmtlib_nc_get_att_vtext is NULL\n");
+		return GMT_RUNTIME_ERROR;
+	}
 	status = nc_inq_attlen (ncid, varid, name, &attlen);
 	if (status != NC_NOERR) {	/* No such attribute */
-		*text = '\0';
+		if (text) text[0] = '\0';
 		return status;
 	}
 	att = calloc (attlen+1, sizeof (char));	/* Allocate the memory for the full string plus text terminator */
@@ -4777,13 +4782,20 @@ int gmtlib_nc_get_att_vtext (struct GMT_CTRL *GMT, int ncid, int varid, char *na
 				HH->remark = att;
 				wipe = false;
 			}
+			else if (strcmp (name, "cpt") == 0) {
+				if (HH->cpt) gmt_M_str_free (HH->cpt);	/* Free previous string */
+				HH->cpt = att;
+				wipe = false;
+			}
+		}
+		if (text) {	/* Only copy over if text was passed */
+			trunclen = MIN (attlen, textlen-1); /* attlen does not include terminating '\0') */
+			strncpy (text, att, trunclen); /* Copy att to text */
+			text[trunclen] = '\0'; /* Terminate string */
 		}
-		trunclen = MIN (attlen, textlen-1); /* attlen does not include terminating '\0') */
-		strncpy (text, att, trunclen); /* Copy att to text */
-		text[trunclen] = '\0'; /* Terminate string */
 	}
-	else	/* Not successful, set ouput string to empty */
-		*text = '\0';
+	else if (text)	/* Not successful, set output string to empty unless NULL */
+		text[0] = '\0';
 	if (wipe) gmt_M_str_free (att);	/* Free since not placed in hidden structure */
 	return status;
 }

src/gmt_nc.c

@@ -896,6 +896,9 @@ GMT_LOCAL int gmtnc_grd_info (struct GMT_CTRL *GMT, struct GMT_GRID_HEADER *head
 			/* Valid range is already in packed units, so do not convert */
 			header->z_min = dummy[0], header->z_max = dummy[1];
 		}
+		if (gmtlib_nc_get_att_vtext (GMT, ncid, z_id, "cpt", header, NULL, 0))	/* Found cpt attribute */
+			GMT_Report (GMT->parent, GMT_MSG_INFORMATION, "netCDF grid %s has a default CPT %s.\n", HH->cpt);
+
 		if (gmt_M_is_dnan (header->z_min) && gmt_M_is_dnan (header->z_max)) {
 			GMT_Report (GMT->parent, GMT_MSG_INFORMATION, "netCDF grid %s information has zmin = zmax = NaN. Reset to 0/0.\n", HH->name);
 			header->z_min = header->z_max = 0.0;
@@ -1029,6 +1032,10 @@ GMT_LOCAL int gmtnc_grd_info (struct GMT_CTRL *GMT, struct GMT_GRID_HEADER *head
 
 		/* Define z variable. Attempt to remove "scale_factor" or "add_offset" when no longer needed */
 		gmtnc_put_units (ncid, z_id, header->z_units);
+		if (GMT->parent->remote_info && GMT->parent->remote_id != GMT_NOTSET && GMT->parent->remote_info[GMT->parent->remote_id].CPT[0] != '-') {	/* Subset of remote grid with default CPT, save name as an attribute */
+			HH->cpt = strdup (GMT->parent->remote_info[GMT->parent->remote_id].CPT);
+			gmt_M_err_trap (nc_put_att_text (ncid, z_id, "cpt", strlen (HH->cpt), HH->cpt));
+		}
 
 		if (header->z_scale_factor != 1.0) {
 			gmt_M_err_trap (nc_put_att_double (ncid, z_id, "scale_factor", NC_DOUBLE, 1U, &header->z_scale_factor));

src/gmt_private.h

@@ -209,6 +209,7 @@ struct GMTAPI_CTRL {
 	char *O_OPT, *K_OPT, *P_OPT, *c_OPT;
 	/* structure array of remote file information (sorted alphabetically) */
 	int n_remote_info;	/* How many remote server files we know of */
+	int remote_id;	/* Currently used remote ID or -1 */
 	struct GMT_DATA_INFO *remote_info;
 	bool server_announced;	/* Set to true after we have announced which GMT data server we are using */
 	struct GMT_COMMON *common_snapshot;	/* Holds the latest GMT common option settings after a module completes. */

src/gmt_prototypes.h

@@ -659,7 +659,7 @@ EXTERN_MSC int gmt_find_macro (char *arg, unsigned int n_macros, struct GMT_MATH
 EXTERN_MSC int gmt_load_macros (struct GMT_CTRL *GMT, char *mtype, struct GMT_MATH_MACRO **M);
 EXTERN_MSC struct GMT_OPTION * gmt_substitute_macros (struct GMT_CTRL *GMT, struct GMT_OPTION *options, char *mfile);
 EXTERN_MSC void gmt_free_macros (struct GMT_CTRL *GMT, unsigned int n_macros, struct GMT_MATH_MACRO **M);
-EXTERN_MSC char * gmt_cpt_default (struct GMTAPI_CTRL *API, char *cpt, char *file);
+EXTERN_MSC char * gmt_cpt_default (struct GMTAPI_CTRL *API, char *cpt, char *file, struct GMT_GRID_HEADER *h);
 EXTERN_MSC void gmt_sort_array (struct GMT_CTRL *GMT, void *base, uint64_t n, unsigned int type);
 EXTERN_MSC bool gmt_polygon_is_open (struct GMT_CTRL *GMT, double x[], double y[], uint64_t n);
 EXTERN_MSC int gmt_polygon_centroid (struct GMT_CTRL *GMT, double *x, double *y, uint64_t n, double *Cx, double *Cy);

src/gmt_remote.c

@@ -477,6 +477,7 @@ void gmt_set_unspecified_remote_registration (struct GMTAPI_CTRL *API, char **fi
 	ext = gmt_chop_ext (infile);
 	/* If the remote file is found then there is nothing to do */
 	if ((k_data = gmt_remote_dataset_id (API, infile)) == GMT_NOTSET) goto clean_up;
+	API->remote_id = k_data;
 	L = strlen (API->remote_info[k_data].dir) - 1;	/* Length of dir minus trailing slash */
 	strncpy (dir, API->remote_info[k_data].dir, L);	dir[L] = '\0';	/* Duplicate dir without slash */
 	p = strrchr (dir, '/') + 1;	/* Start of final subdirectory (skipping over the slash we found) */
@@ -498,6 +499,7 @@ void gmt_set_unspecified_remote_registration (struct GMTAPI_CTRL *API, char **fi
 			}
 			gmt_M_str_free (*file_ptr);
 			*file_ptr = strdup (newfile);
+			API->remote_id = k_data;
 			goto clean_up;
 		}
 	}

src/gmt_support.c

@@ -8337,7 +8337,7 @@ struct GMT_PALETTE * gmtlib_read_cpt (struct GMT_CTRL *GMT, void *source, unsign
 	return (X);
 }
 
-char * gmt_cpt_default (struct GMTAPI_CTRL *API, char *cpt, char *file) {
+char * gmt_cpt_default (struct GMTAPI_CTRL *API, char *cpt, char *file, struct GMT_GRID_HEADER *h) {
 	/* Return which type of default CPT this data set should use.
 	 * If cpt is specified then that is what we will use. If not, then
 	 * we determine if file is a remote data set, and if it is and has a
@@ -8346,20 +8346,42 @@ char * gmt_cpt_default (struct GMTAPI_CTRL *API, char *cpt, char *file) {
 	int k_data;
 	static char *srtm_cpt = "srtm";
 	char *curr_cpt = NULL;
+	struct GMT_GRID_HEADER_HIDDEN *HH = gmt_get_H_hidden (h);
 
-	if (cpt) return strdup (cpt);	/* CPT was already specified */
-	if (file == NULL) return NULL;	/* No file given, so there */
-	if (API->GMT->current.setting.run_mode == GMT_MODERN && (curr_cpt = gmt_get_current_item (API->GMT, "cpt", false))) return curr_cpt;	/* Use current CPT */
+	if (cpt) {
+		GMT_Report (API, GMT_MSG_INFORMATION, "gmt_cpt_default: Use specific CPT: %s\n", cpt);
+		return strdup (cpt);	/* CPT was already specified, so use it */
+	}
+	if (file == NULL) {
+		GMT_Report (API, GMT_MSG_INFORMATION, "gmt_cpt_default: No file given so cannot determine\n");
+		return NULL;	/* No file given, so nothing to work with */
+	}
+	if (API->GMT->current.setting.run_mode == GMT_MODERN && (curr_cpt = gmt_get_current_item (API->GMT, "cpt", false))) {
+		GMT_Report (API, GMT_MSG_INFORMATION, "gmt_cpt_default: Use current CPT: %s\n", curr_cpt);
+		return curr_cpt;	/* Use current CPT */
+	}
+	if (HH->cpt && HH->cpt[0] != '-') {
+		GMT_Report (API, GMT_MSG_INFORMATION, "gmt_cpt_default: Use grid header default CPT: %s\n", HH->cpt);
+		return (strdup (HH->cpt));	/* Found default CPT in the grid header */
+	}
 
+	/* Check if we are reading a remote dataset with a default CPT */
 	if ((k_data = gmt_remote_dataset_id (API, file)) == GMT_NOTSET) {
 		size_t LOX;
 		if ((k_data = gmt_get_tile_id (API, file)) == GMT_NOTSET)
 			return NULL;	/* Go with the default, whatever that is */
 		LOX = strlen (file) - 8;	/* Position of the L|O|X flag */
-		if (file[LOX] == 'L') return strdup (srtm_cpt);
+		if (file[LOX] == 'L') {
+			GMT_Report (API, GMT_MSG_INFORMATION, "gmt_cpt_default: Use SRTM default CPT: %s\n", srtm_cpt);
+			return strdup (srtm_cpt);
+		}
+	}
+	if (API->remote_info[k_data].CPT[0] == '-') {
+			GMT_Report (API, GMT_MSG_INFORMATION, "gmt_cpt_default: No CPT default for remote dataset %s\n", file);
+		return (NULL);
 	}
-	if (API->remote_info[k_data].CPT[0] == '-') return (NULL);
 
+	GMT_Report (API, GMT_MSG_INFORMATION, "gmt_cpt_default: Use dataset default CPT: %s\n", API->remote_info[k_data].CPT);
 	return (strdup (API->remote_info[k_data].CPT));
 }
 
@@ -8489,7 +8511,8 @@ struct GMT_PALETTE *gmt_get_palette (struct GMT_CTRL *GMT, char *file, enum GMT_
 
 	if (mode == GMT_CPT_REQUIRED) {	/* The calling function requires the CPT to be present; GMT_Read_Data will work or fail accordingly */
 		P = GMT_Read_Data (GMT->parent, GMT_IS_PALETTE, GMT_IS_FILE, GMT_IS_NONE, GMT_READ_NORMAL|continuous, NULL, file, NULL);
-		gmt_save_current_cpt (GMT, P, 0);	/* Save for use by session, if modern */
+		if (GMT->parent->gwf_dir == NULL || file == NULL || strstr (file, GMT->parent->gwf_dir) == NULL)	/* Avoid writing a sessions CPT to a sessions CPT */
+			gmt_save_current_cpt (GMT, P, 0);	/* Save for use by session, if modern mode */
 		return (P);
 	}
 
@@ -8553,7 +8576,8 @@ struct GMT_PALETTE *gmt_get_palette (struct GMT_CTRL *GMT, char *file, enum GMT_
 	else
 		GMT_Report (GMT->parent, GMT_MSG_ERROR, "No CPT file or master given?\n");
 
-	gmt_save_current_cpt (GMT, P, 0);	/* Save for use by session, if modern */
+	if (GMT->parent->gwf_dir == NULL || file == NULL || strstr (file, GMT->parent->gwf_dir) == NULL)	/* Avoid writing a sessions CPT to a sessions CPT */
+		gmt_save_current_cpt (GMT, P, 0);	/* Save for use by session, if modern */
 	return (P);
 }
 

src/grd2kml.c

@@ -695,7 +695,7 @@ EXTERN_MSC int GMT_grd2kml (void *V_API, int mode, void *args) {
 	}
 
 	if (!Ctrl->C.active || gmt_is_cpt_master (GMT, Ctrl->C.file)) {	/* If no cpt given or just a master then we must compute a scaled one from the full-size grid and use it throughout */
-		char *cpt = gmt_cpt_default (API, Ctrl->C.file, Ctrl->In.file);
+		char *cpt = gmt_cpt_default (API, Ctrl->C.file, Ctrl->In.file, G->header);
 		char cptfile[PATH_MAX] = {""};
 		struct GMT_PALETTE *P = NULL;
 		if ((P = gmt_get_palette (GMT, cpt, GMT_CPT_OPTIONAL, G->header->z_min, G->header->z_max, Ctrl->C.dz)) == NULL) {

src/grdcut.c

@@ -1024,9 +1024,14 @@ EXTERN_MSC int GMT_grdcut (void *V_API, int mode, void *args) {
 	/* Send the subset of the grid or image to the gridfile destination. */
 
 	if (Ctrl->In.type == GMT_IS_GRID) {	/* Write a grid */
-		if (GMT_Set_Comment (API, GMT_IS_GRID, GMT_COMMENT_IS_OPTION | GMT_COMMENT_IS_COMMAND, options, G)) Return (API->error);
-		if (GMT_Write_Data (API, GMT_IS_GRID, GMT_IS_FILE, GMT_IS_SURFACE, GMT_CONTAINER_AND_DATA, NULL, Ctrl->G.file, G) != GMT_NOERROR) {
+		if (GMT_Set_Comment (API, GMT_IS_GRID, GMT_COMMENT_IS_OPTION | GMT_COMMENT_IS_COMMAND, options, G))
 			Return (API->error);
+		if (GMT_Write_Data (API, GMT_IS_GRID, GMT_IS_FILE, GMT_IS_SURFACE, GMT_CONTAINER_AND_DATA, NULL, Ctrl->G.file, G) != GMT_NOERROR)
+			Return (API->error);
+		if (GMT->current.setting.run_mode == GMT_MODERN && HH->cpt) {	/* Save the CPT as the current CPT for a modern mode session */
+			struct GMT_PALETTE *P = gmt_get_palette (GMT, HH->cpt, GMT_CPT_OPTIONAL, G->header->z_min, G->header->z_max, 0.0);
+			if (GMT_Destroy_Data (API, &P) != GMT_NOERROR)
+				Return (API->error);
 		}
 	}
 	else {	/* Write an image */

src/grdimage.c

@@ -1581,7 +1581,7 @@ EXTERN_MSC int GMT_grdimage (void *V_API, int mode, void *args) {
 	has_content = (got_z_grid) ? false : true;	/* Images always have content but grids may be all NaN */
 	if (got_z_grid) {	/* Got a single grid so need to convert z to color via a CPT */
 		if (Ctrl->C.active) {	/* Read a palette file */
-			char *cpt = gmt_cpt_default (API, Ctrl->C.file, Ctrl->In.file);
+			char *cpt = gmt_cpt_default (API, Ctrl->C.file, Ctrl->In.file, Grid_orig->header);
 			if ((P = gmt_get_palette (GMT, cpt, GMT_CPT_OPTIONAL, Grid_orig->header->z_min, Grid_orig->header->z_max, Ctrl->C.dz)) == NULL) {
 				GMT_Report (API, GMT_MSG_ERROR, "Failed to read CPT %s.\n", Ctrl->C.file);
 				gmt_free_header (API->GMT, &header_G);

src/grdview.c

@@ -979,7 +979,7 @@ EXTERN_MSC int GMT_grdview (void *V_API, int mode, void *args) {
 
 	if (Ctrl->C.active) {
 		char *dataset_cpt = (Ctrl->G.active && Ctrl->G.n == 1 && !gmt_M_file_is_image (Ctrl->G.file[0])) ? Ctrl->G.file[0] : Ctrl->In.file;
-		char *cpt = gmt_cpt_default (API, Ctrl->C.file, dataset_cpt);
+		char *cpt = gmt_cpt_default (API, Ctrl->C.file, dataset_cpt, Topo->header);
 		if ((P = gmt_get_palette (GMT, cpt, GMT_CPT_OPTIONAL, Topo->header->z_min, Topo->header->z_max, Ctrl->C.dz)) == NULL) {
 			Return (API->error);
 		}

test/grdcut/polycut.sh

@@ -10,9 +10,9 @@ gmt begin polycut
 	gmt grdcut @earth_relief_30m -FFR.txt+c+i -GFR_not.grd
 	# Like first, but retain input region
 	gmt grdcut @earth_relief_30m -FFR.txt -GFR_world.grd
-	gmt grdimage FR_world.grd -B -Rd -JQ0/18c
+	gmt grdimage FR_world.grd -B -Rd -JQ0/18c -Cturbo
 	gmt subplot begin 1x2 -Fs8.5c -Scb -Srl -RFR -JM8.5c -M0.35c -Yh+1c
-		gmt grdimage FR_only.grd -c
+		gmt grdimage FR_only.grd -Cturbo -c
 		gmt grdimage FR_not.grd -c
 	gmt subplot end
 gmt end show

test/grdfilter/highpass.sh

@@ -7,9 +7,9 @@ gmt grdfilter AFR.nc -Fg100+h -D2 -GHc.nc -I15m
 gmt grdfilter AFR.nc -Fg100 -D2 -GLc.nc -I15m
 gmt grdfilter AFR.nc -Fg100+h -D2 -GHf.nc
 gmt grdfilter AFR.nc -Fg100 -D2 -GLf.nc
-gmt grdimage AFR.nc -JM3i -I -P -K -Baf -BWSne -Y0.75i > $ps
+gmt grdimage AFR.nc -JM3i -I -P -K -Baf -BWSne -Y0.75i -Cturbo > $ps
 gmt grdimage Lc.nc -J -I -O -K -Baf -BWsne -Y3.25i >> $ps
 gmt grdimage Hc.nc -J -I -O -K -Baf -BWsne -Y3.25i >> $ps
-gmt grdimage AFR.nc -J -I -O -K -Baf -BWSnE -X3.5i -Y-6.5i >> $ps
+gmt grdimage AFR.nc -J -I -O -K -Baf -BWSnE -X3.5i -Y-6.5i -Cturbo >> $ps
 gmt grdimage Lf.nc -J -I -O -K -Baf -BWsnE -Y3.25i >> $ps
 gmt grdimage Hf.nc -J -I -O -Baf -BWsnE -Y3.25i >> $ps