d.rast.arrow: do not draw unknown and null values when color is none

since none was allowed by interface it also fixes bug in wxGUI where setting Transparent caused the module to fail and layer not to render

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@60382 15284696-431f-4ddb-bdfa-cd5b030d7da7

display/d.rast.arrow/d.rast.arrow.html

@@ -16,6 +16,9 @@ layer has a category value denoting locations of "unknown" aspect,
 <em>d.rast.arrow</em> draws a question mark over the displayed cells
 of that category.
 Cells containing null data will be marked with an "X".
+You can disable drawing of null data and unknown aspect values by
+setting its color to "<tt>none</tt>".
+
 <p>If you specify the <em>magnitude_map</em> option, arrow lengths 
 denoting magnitude will be extracted from the cell values of the specified 
 map. In this case the tail of the arrow will be centered on the source cell.

display/d.rast.arrow/main.c

@@ -124,7 +124,9 @@ int main(int argc, char **argv)
     opt4->required = NO;
     opt4->answer = "gray";
     opt4->gisprompt = "old,color_none,color";
-    opt4->description = _("Color for drawing grid or \"none\"");
+    opt4->label = _("Color for drawing drawing grid");
+    opt4->description = _("Color in GRASS format for drawing grid"
+	" or \"none\" not drawing");
     opt4->guisection = _("Colors");
 
     opt5 = G_define_option();
@@ -133,7 +135,9 @@ int main(int argc, char **argv)
     opt5->required = NO;
     opt5->answer = DEFAULT_FG_COLOR;
     opt5->gisprompt = "old,color_none,color";
-    opt5->description = _("Color for drawing X's (null values)");
+    opt5->label = _("Color for drawing null values");
+    opt5->description = _("Color in GRASS format for drawing null values"
+	" (X symbol) or \"none\" not drawing");
     opt5->guisection = _("Colors");
 
     opt6 = G_define_option();
@@ -142,7 +146,10 @@ int main(int argc, char **argv)
     opt6->required = NO;
     opt6->answer = "red";
     opt6->gisprompt = "old,color_none,color";
-    opt6->description = _("Color for showing unknown information");
+    opt6->description = _("Color for showing unknown information or \"none\"");
+    opt6->label = _("Color for showing unknown information");
+    opt6->description = _("Color in GRASS format for showing unknown"
+	" information (? symbol) or \"none\" not showing");
     opt6->guisection = _("Colors");
 
     opt9 = G_define_option();
@@ -181,14 +188,26 @@ int main(int argc, char **argv)
     layer_name = opt1->answer;
 
     arrow_color = D_translate_color(opt3->answer);
-    x_color = D_translate_color(opt5->answer);
-    unknown_color = D_translate_color(opt6->answer);
 
+    /* Convert none (transparent) to -1 which in this module means
+       that we will not draw things having this color (-1).
+       We don't do that for arrow because we always want them.
+       (This is specified by the gisprompt ('type') of the options.)
+    */
     if (strcmp("none", opt4->answer) == 0)
 	grid_color = -1;
     else
 	grid_color = D_translate_color(opt4->answer);
 
+    if (strcmp("none", opt5->answer) == 0)
+	x_color = -1;
+    else
+	x_color = D_translate_color(opt5->answer);
+
+    if (strcmp("none", opt6->answer) == 0)
+	unknown_color = -1;
+    else
+	unknown_color = D_translate_color(opt6->answer);
 
     if (strcmp("grass", opt2->answer) == 0)
 	map_type = 1;
@@ -390,9 +409,12 @@ int main(int argc, char **argv)
 		D_use_color(arrow_color);
 
 		if (Rast_is_null_value(ptr, raster_type)) {
-		    D_use_color(x_color);
-		    draw_x();
-		    D_use_color(arrow_color);
+		    /* don't draw anything if x_color is none (transparent) */
+		    if (x_color > 0) {
+			D_use_color(x_color);
+			draw_x();
+			D_use_color(arrow_color);
+		    }
 		}
 		else if (aspect_f >= 0.0 && aspect_f <= 360.0) {
 		    if (opt7->answer)
@@ -400,7 +422,8 @@ int main(int argc, char **argv)
 		    else
 			arrow_360(aspect_f);
 		}
-		else {
+		else if (unknown_color > 0) {
+		    /* don't draw if unknown_color is none (transparent) */
 		    D_use_color(unknown_color);
 		    unknown_();
 		    D_use_color(arrow_color);
@@ -413,9 +436,12 @@ int main(int argc, char **argv)
 		D_use_color(arrow_color);
 		switch (aspect_c) {
 		case 0:
-		    D_use_color(x_color);
-		    draw_x();
-		    D_use_color(arrow_color);
+		    /* only draw if x_color is not none (transparent) */
+		    if (x_color > 0) {
+			D_use_color(x_color);
+			draw_x();
+			D_use_color(arrow_color);
+		    }
 		    break;
 		case 1:
 		    arrow_n();
@@ -442,9 +468,12 @@ int main(int argc, char **argv)
 		    arrow_nw();
 		    break;
 		default:
-		    D_use_color(unknown_color);
-		    unknown_();
-		    D_use_color(arrow_color);
+		    /* only draw if unknown_color is not none */
+		    if (unknown_color > 0) {
+			D_use_color(unknown_color);
+			unknown_();
+			D_use_color(arrow_color);
+		    }
 		    break;
 		}
 	    }
@@ -456,11 +485,15 @@ int main(int argc, char **argv)
 		if (aspect_c >= 15 && aspect_c <= 360)	/* start at zero? */
 		    arrow_360((double)aspect_c);
 		else if (aspect_c == 400) {
-		    D_use_color(unknown_color);
-		    unknown_();
-		    D_use_color(arrow_color);
+		    if (unknown_color > 0) {
+			/* only draw if unknown_color is not none */
+			D_use_color(unknown_color);
+			unknown_();
+			D_use_color(arrow_color);
+		    }
 		}
-		else {
+		else if (x_color > 0) {
+		    /* only draw if x_color is not none (transparent) */
 		    D_use_color(x_color);
 		    draw_x();
 		    D_use_color(arrow_color);
@@ -473,9 +506,12 @@ int main(int argc, char **argv)
 		D_use_color(arrow_color);
 
 		if (Rast_is_null_value(ptr, raster_type)) {
-		    D_use_color(x_color);
-		    draw_x();
-		    D_use_color(arrow_color);
+		    if (x_color > 0) {
+			/* only draw if x_color is not none */
+			D_use_color(x_color);
+			draw_x();
+			D_use_color(arrow_color);
+		    }
 		}
 		else if (aspect_f >= 0.0 && aspect_f <= 360.0) {
 		    if (opt7->answer)
@@ -483,7 +519,8 @@ int main(int argc, char **argv)
 		    else
 			arrow_360(90 - aspect_f);
 		}
-		else {
+		else if (unknown_color > 0) {
+		    /* only draw if unknown_color is not none */
 		    D_use_color(unknown_color);
 		    unknown_();
 		    D_use_color(arrow_color);