Check for error if CPT has non-zero hinge

doc/rst/source/reference/features.rst

@@ -1386,7 +1386,7 @@ are identified as such via the special comment
 
 | ``# HARD_HINGE``
 
-and all hard hinges occur at data value *z = 0* (but you can change this value by
+and all hard hinges must occur at data value *z = 0* (but you can change this value by
 adding **+h**\ *value* to the name of the CPT).
 Other CPTs may instead have a *soft* hinge which indicates a natural hinge or transition
 point in the CPT itself, unrelated to any natural data set *per se*. These CPTs
@@ -1397,6 +1397,7 @@ are flagged by the special comment
 CPTs with soft hinges behave as regular (non-hinge) CPTs *unless* the user activates then by
 appending **+h**\ [*hinge*] to the CPT name.  This modifier will convert the soft
 hinge into a hard hinge at the user-specified data value *hinge* [which defaults to 0].
+As for hard hinges, soft hinges must occur at data value *z = 0* in the CPT.
 Note that if your specified data range *excludes* an activated soft or hard hinge then we
 only perform color sampling from the *half* of the CPT that pertains to the data range.
 All dynamic CPTs will need to be stretched to the user's preferred range, and there

src/gmt_prototypes.h

@@ -577,7 +577,7 @@ EXTERN_MSC bool gmt_x_out_of_bounds (struct GMT_CTRL *GMT, int *i, struct GMT_GR
 EXTERN_MSC bool gmt_row_col_out_of_bounds (struct GMT_CTRL *GMT, double *in, struct GMT_GRID_HEADER *h, openmp_int *row, openmp_int *col);
 EXTERN_MSC int gmt_list_cpt (struct GMT_CTRL *GMT, char option);
 EXTERN_MSC void gmt_scale_cpt (struct GMT_CTRL *GMT, struct GMT_PALETTE *P, double scale);
-EXTERN_MSC void gmt_stretch_cpt (struct GMT_CTRL *GMT, struct GMT_PALETTE *P, double z_low, double z_high);
+EXTERN_MSC unsigned int gmt_stretch_cpt (struct GMT_CTRL *GMT, struct GMT_PALETTE *P, double z_low, double z_high);
 EXTERN_MSC struct GMT_PALETTE * gmt_sample_cpt (struct GMT_CTRL *GMT, struct GMT_PALETTE *Pin, double z[], int nz, bool continuous, bool reverse, bool log_mode, bool no_inter);
 EXTERN_MSC void gmt_invert_cpt (struct GMT_CTRL *GMT, struct GMT_PALETTE *P);
 EXTERN_MSC void gmt_undo_log10 (struct GMT_CTRL *GMT, struct GMT_PALETTE *P);

src/gmt_support.c

@@ -1468,8 +1468,8 @@ GMT_LOCAL int gmtsupport_find_cpt_hinge (struct GMT_CTRL *GMT, struct GMT_PALETT
 		GMT_Report (GMT->parent, GMT_MSG_DEBUG, "Found CPT hinge at z' = 0 for slice k = %u!\n", k);
 		return (int)k;
 	}
-	GMT_Report (GMT->parent, GMT_MSG_WARNING, "Hinge requested but no hinge at z' = 0 was found in this CPT\n");
-	return GMT_NOTSET;
+	GMT_Report (GMT->parent, GMT_MSG_ERROR, "Hinge requested but no hinge at z' = 0 was found in this CPT\n");
+	return GMT_PARSE_ERROR;
 }
 
 /*! . */
@@ -9041,7 +9041,7 @@ struct GMT_PALETTE *gmt_get_palette (struct GMT_CTRL *GMT, char *file, enum GMT_
 		}
 		PH = gmt_get_C_hidden (P);
 		PH->auto_scale = 1;	/* Flag for colorbar to supply -Baf if not given */
-		gmt_stretch_cpt (GMT, P, zmin, zmax);
+		if ((gmt_stretch_cpt (GMT, P, zmin, zmax)) == GMT_PARSE_ERROR) return (NULL);
 	}
 	else if (file) {	/* Gave a CPT file */
 		GMT_Report (GMT->parent, GMT_MSG_DEBUG, "CPT argument %s understood to be a regular CPT table\n", file);
@@ -9098,6 +9098,7 @@ GMT_LOCAL int gmtsupport_validate_cpt (struct GMT_CTRL *GMT, struct GMT_PALETTE
 	if (!P->has_hinge) return GMT_NOTSET;	/* Not our concern here */
 	/* Claims to have a hinge */
 	ks = gmtsupport_find_cpt_hinge (GMT, P);	/* Get hinge slice (or -1 if no hinge found) */
+	if (ks == GMT_PARSE_ERROR) return (GMT_PARSE_ERROR);
 	if (ks == GMT_NOTSET) {	/* Must be a rogue CPT - ignore the hinge setting */
 		GMT_Report (GMT->parent, GMT_MSG_WARNING, "gmt_stretch_cpt: CPT says it has a hinge but none is actually found? - ignored.\n");
 		P->has_hinge = 0;
@@ -9123,7 +9124,7 @@ GMT_LOCAL int gmtsupport_validate_cpt (struct GMT_CTRL *GMT, struct GMT_PALETTE
 }
 
 /*! . */
-void gmt_stretch_cpt (struct GMT_CTRL *GMT, struct GMT_PALETTE *P, double z_low, double z_high) {
+unsigned int gmt_stretch_cpt (struct GMT_CTRL *GMT, struct GMT_PALETTE *P, double z_low, double z_high) {
 	/* Replace CPT z-values with new ones linearly scaled from z_low to z_high.  If these are
 	 * zero then we substitute the CPT's default range instead (if available).
 	 * Note: If P has a hinge then its value is expected to be in the final user data values.
@@ -9138,11 +9139,11 @@ void gmt_stretch_cpt (struct GMT_CTRL *GMT, struct GMT_PALETTE *P, double z_low,
 	if (z_low == z_high) {	/* Range information not given, rely on CPT RANGE setting */
 		if (P->has_range == 0) {
 			GMT_Report (GMT->parent, GMT_MSG_DEBUG, "gmt_stretch_cpt: Passed z_low == z_high but CPT has no explicit range.  No changes made\n");
-			return;
+			return GMT_NOERROR;
 		}
 		z_low = P->minmax[0];	z_high = P->minmax[1];
 	}
-	ks = gmtsupport_validate_cpt (GMT, P, &z_low, &z_high);	/* Deal with any issure related to hinges */
+	if ((ks = gmtsupport_validate_cpt (GMT, P, &z_low, &z_high)) == GMT_PARSE_ERROR) return (GMT_PARSE_ERROR);	/* Deal with any issue related to hinges */
 
 	z_min = P->data[0].z_low;
 	z_start = z_low;
@@ -9160,6 +9161,7 @@ void gmt_stretch_cpt (struct GMT_CTRL *GMT, struct GMT_PALETTE *P, double z_low,
 		P->data[is].z_high = z_start + (P->data[is].z_high - z_min) * scale;
 		P->data[is].i_dz /= scale;
 	}
+	return (GMT_NOERROR);
 }
 
 /*! . */
@@ -9743,7 +9745,7 @@ struct GMT_PALETTE * gmt_truncate_cpt (struct GMT_CTRL *GMT, struct GMT_PALETTE
 	 * expand it to its natural z-range before we can truncate since z_low/z_high are in user units */
 
 	if (P->has_range) {
-		gmt_stretch_cpt (GMT, P, 0.0, 0.0);	/* Stretch to its natural range first */
+		if ((gmt_stretch_cpt (GMT, P, 0.0, 0.0)) == GMT_PARSE_ERROR) return NULL;	/* Stretch to its natural range first */
 		P->has_range = 0;
 	}
 

src/grd2cpt.c

@@ -710,7 +710,8 @@ EXTERN_MSC int GMT_grd2cpt (void *V_API, int mode, void *args) {
 
 	if (Ctrl->E.active && Ctrl->E.levels == 0) {	/* Use existing CPT structure, just linearly change z */
 		if ((Pout = GMT_Duplicate_Data (API, GMT_IS_PALETTE, GMT_DUPLICATE_ALLOC, Pin)) == NULL) return (API->error);
-		gmt_stretch_cpt (GMT, Pout, Ctrl->L.min, Ctrl->L.max);
+		if ((gmt_stretch_cpt (GMT, Pout, Ctrl->L.min, Ctrl->L.max)) == GMT_PARSE_ERROR)
+			Return (GMT_RUNTIME_ERROR);
 		if (Ctrl->I.mode & GMT_CPT_C_REVERSE)
 			gmt_invert_cpt (GMT, Pout);	/* Also flip the colors */
 		cpt_flags = 0;

src/makecpt.c

@@ -630,7 +630,9 @@ EXTERN_MSC int GMT_makecpt (void *V_API, int mode, void *args) {
 	}
 	if (!Ctrl->T.interpolate) {	/* Just copy what was in the CPT but stretch to given range min/max */
 		if ((Pout = GMT_Duplicate_Data (API, GMT_IS_PALETTE, GMT_DUPLICATE_ALLOC, Pin)) == NULL) return (API->error);
-		gmt_stretch_cpt (GMT, Pout, Ctrl->T.T.min, Ctrl->T.T.max);	/* Stretch to given range or use natural range if 0/0 */
+		/* Stretch to given range or use natural range if 0/0 */
+		if ((gmt_stretch_cpt (GMT, Pout, Ctrl->T.T.min, Ctrl->T.T.max)) == GMT_PARSE_ERROR)
+			Return (GMT_RUNTIME_ERROR);
 		if (Ctrl->I.mode & GMT_CPT_C_REVERSE)	/* Also flip the colors */
 			gmt_invert_cpt (GMT, Pout);
 		if (Ctrl->Q.mode == 1)

src/psscale.c

@@ -1922,8 +1922,10 @@ EXTERN_MSC int GMT_psscale (void *V_API, int mode, void *args) {
 		Ctrl->D.emode &= 4;	/* This removes any 1,2,3 of selected but leaves 4 for nan */
 	}
 
-	if (P->has_range)	/* Convert from normalized to default CPT z-range */
-		gmt_stretch_cpt (GMT, P, 0.0, 0.0);
+	if (P->has_range) {	/* Convert from normalized to default CPT z-range */
+		if ((gmt_stretch_cpt (GMT, P, 0.0, 0.0)) == GMT_PARSE_ERROR)
+			Return (GMT_RUNTIME_ERROR);
+	}
 
 	if (P->categorical && (Ctrl->D.emode & 1 || Ctrl->D.emode & 2)) {
 			GMT_Report (API, GMT_MSG_WARNING, "Option -D: Cannot select back/fore-ground extender for categorical CPT\n");