Fix a regression that was causing failure of categorical test.

.github/workflows/build.yml

@@ -54,7 +54,7 @@ jobs:
           - name: Linux
             os: ubuntu-latest
           - name: macOS
-            os: macos-latest
+            os: macos-15-intel
           - name: Windows
             os: windows-latest
           - name: Linux (without optional dependencies)

.github/workflows/tests.yml

@@ -54,7 +54,7 @@ jobs:
           - name: Linux
             os: ubuntu-latest
           - name: macOS
-            os: macos-13 # macos-14 use M1 chips, which causes many failures
+            os: macos-15-intel # macos-14 use M1 chips, which causes many failures
           - name: Windows
             os: windows-latest
 

doc/rst/source/grdview.rst

@@ -19,7 +19,7 @@ Synopsis
 [ |-I|\ [*file*\|\ *intens*\|\ **+a**\ *azimuth*][**+d**][**+m**\ *ambient*][**+n**\ *args*] ]
 [ |-Jz|\ \|\ **Z**\ *parameters* ]
 [ |-N|\ [*level*]\ [**+g**\ *fill*] ]
-[ |-Q|\ **c**\|\ **i**\|\ **m**\ [**x**\|\ **y**]\|\ **s**\ [**m**]\|\ **g**\ [**m**]\ [*color*][**+m**] ]
+[ |-Q|\ **c**\|\ **g**\ [**m**]\ **i**\|\ **m**\ [**x**\|\ **y**]\|\ **s**\ [**m**]\|\ [*color*][**+m**]\ **t** ]
 [ |SYN_OPT-Rz| ]
 [ |-S|\ *smooth* ]
 [ |-T|\ [**+o**\ [*pen*]][**+s**] ]
@@ -101,24 +101,26 @@ Optional Arguments
 
 .. _-Q:
 
-**-Q**\ **c**|\ **g**[**m**][**a**]|\ **i**|\ **m**\ [**x**|\ **y**]|\ **s**\ [**m**]\ [*color*][**+m**]
+**-Q**\ **c**\|\ **g**\ [**m**]\ **i**\|\ **m**\ [**x**\|\ **y**]\|\ **s**\ [**m**]\|\ [*color*][**+m**]\ **t**
     Select one of following directives. For any of these choices:
 
     - **c** - Image plot, but will make nodes with *z* = NaN transparent, using the color-masking
       feature in PostScript Level 3. Optionally append the effective dots-per-unit resolution
       for the rasterization [Default is :term:`GMT_GRAPHICS_DPU`].
-    - **i** - Image plot. Optionally append the effective dots-per-unit resolution for the
-      rasterization [Default is :term:`GMT_GRAPHICS_DPU`].
-    - **m** - Mesh plot [Default]. Optionally append *color* for a different mesh paint [white].
-      For waterfall plots, append **x** for row or **y** for column profiles. Specify color as for plain **m**.
-    - **s** - Surface plot. Optionally append **m** to have mesh lines drawn on top of surface. See **-Wm** for
-      setting a specific mesh *pen*.
     - **g** - Gouraud-shaded surface with smooth vertex-based color gradients. Optionally append **m** to draw mesh lines
       on top of the surface. Append **a** to use alternate diagonal when splitting tiles into triangles.
       Gouraud shading produces smoother color transitions than **-Qs** and generates significantly smaller
       and faster PostScript files. The **-Qs** option should be used though when precise color transitions
       are required at contour levels (to do a `contourf` type figure. See **-Wc**) because the Gouraud-shaded
       doesn't cut the tiles along the contour lines as **-Qs** does.
+    - **i** - Image plot. Optionally append the effective dots-per-unit resolution for the
+      rasterization [Default is :term:`GMT_GRAPHICS_DPU`].
+    - **m** - Mesh plot [Default]. Optionally append *color* for a different mesh paint [white].
+      For waterfall plots, append **x** for row or **y** for column profiles. Specify color as for plain **m**.
+    - **s** - Surface plot. Optionally append **m** to have mesh lines drawn on top of surface. See **-Wm** for
+      setting a specific mesh *pen*.
+    - **t** - Paint tiles without color interpolation. Good for categorical data. Optionally append the effective
+      dots-per-unit resolution for the rasterization [Default is :term:`GMT_GRAPHICS_DPU`].
 
     A modifier can adjust the color further:
 

src/grdview.c

@@ -504,7 +504,7 @@ static int usage (struct GMTAPI_CTRL *API, int level) {
 	const char *name = gmt_show_name_and_purpose (API, THIS_MODULE_LIB, THIS_MODULE_CLASSIC_NAME, THIS_MODULE_PURPOSE);
 	if (level == GMT_MODULE_PURPOSE) return (GMT_NOERROR);
 	GMT_Usage (API, 0, "usage: %s <topogrid> %s [%s] [-C%s] [-G<drapegrid>|<drapeimage>] "
-		"[-I[<intensgrid>|<value>|<modifiers>]] [%s] %s[-N[<level>][+g<fill>]] %s%s[-Qc|i|m[x|y]|s[<color>][+m]] [%s] [-S<smooth>] "
+		"[-I[<intensgrid>|<value>|<modifiers>]] [%s] %s[-N[<level>][+g<fill>]] %s%s[-Qc|g[m|a]|i|m[x|y]|s[<color>][+m]] [%s] [-S<smooth>] "
 		"[-T[+o[<pen>]][+s]] [%s] [%s] [-W<type><pen>] [%s] [%s] %s[%s] [%s] [%s] [%s] [%s]\n",
 		name, GMT_J_OPT, GMT_B_OPT, CPT_OPT_ARGS, GMT_Jz_OPT, API->K_OPT, API->O_OPT, API->P_OPT, GMT_Rgeoz_OPT, GMT_U_OPT, GMT_V_OPT,
 		GMT_X_OPT, GMT_Y_OPT, API->c_OPT, GMT_f_OPT, GMT_n_OPT, GMT_p_OPT, GMT_t_OPT, GMT_PAR_OPT);
@@ -542,13 +542,14 @@ static int usage (struct GMTAPI_CTRL *API, int level) {
 	GMT_Usage (API, 3, "c: Transform polygons to raster-image via scanline conversion. Append effective <dpu> [%lg%c]. "
 		"Set PS Level 3 color-masking for nodes with z = NaN.",
 		API->GMT->current.setting.graphics_dpu, API->GMT->current.setting.graphics_dpu_unit);
+	GMT_Usage (API, 3, "g: Gouraud-shaded surface with smooth vertex-based color gradients. Append m to draw mesh-lines. Append a for alternate diagonal algorithm.");
 	GMT_Usage (API, 3, "i: As c but no color-masking. Append effective <dpu> [%lg%c].",
 		API->GMT->current.setting.graphics_dpu, API->GMT->current.setting.graphics_dpu_unit);
 	GMT_Usage (API, 3, "m: Mesh plot [Default]. Append <color> for mesh paint [%s]. "
 		"Alternatively, append x or y for row or column \"waterfall\" profiles.",
 		gmt_putcolor (API->GMT, API->GMT->PSL->init.page_rgb));
 	GMT_Usage (API, 3, "s: Colored or shaded surface. Optionally, append m to draw mesh-lines on the surface.");
-	GMT_Usage (API, 3, "g: Gouraud-shaded surface with smooth vertex-based color gradients. Append m to draw mesh-lines. Append a for alternate diagonal.");
+	GMT_Usage (API, 3, "t: Paint tiles without color interpolation. Good for categorical data.");
 	GMT_Usage (API, -2, "Color may be further adjusted by a modifier:");
 	GMT_Usage (API, 3, "+m Force a monochrome image using the YIQ transformation.");
 	GMT_Option (API, "R");
@@ -733,20 +734,19 @@ static int parse (struct GMT_CTRL *GMT, struct GRDVIEW_CTRL *Ctrl, struct GMT_OP
 						Ctrl->Q.cpt = true;	/* Will need a CPT */
 						Ctrl->Q.mask = true;
 						break;
-					case 't':	/* Image without color interpolation */
-						Ctrl->Q.special = true;
-						Ctrl->Q.cpt = true;	/* Will need a CPT */
-						/* Intentionally fall through - to 'i' */
 					case 'g':	/* Gouraud-shaded surface */
 						Ctrl->Q.mode = GRDVIEW_SURF;
 						Ctrl->Q.gouraud = true;
 						Ctrl->Q.cpt = true;		/* Will need a CPT */
 						if (opt->arg[1] == 'm') Ctrl->Q.outline = 1;
 						if (opt->arg[1] == 'a') Ctrl->Q.diagonal = 1;
 						break;
+					case 't':	/* Image without color interpolation */
+						Ctrl->Q.special = true;
+						/* Intentionally fall through - to 'i' */
 					case 'i':	/* Image with clipmask */
 						Ctrl->Q.mode = GRDVIEW_IMAGE;
-						if (opt->arg[1] && isdigit ((int)opt->arg[1])) Ctrl->Q.dpi = grdview_get_dpi (&opt->arg[1]);
+						if (opt->arg[1] && isdigit((int)opt->arg[1])) Ctrl->Q.dpi = grdview_get_dpi(&opt->arg[1]);
 						Ctrl->Q.cpt = true;	/* Will need a CPT */
 						break;
 					case 'm':	/* Mesh plot */