support d.northarrow in parser HTML, use filenames matching options, center drawing in image middle

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@68946 15284696-431f-4ddb-bdfa-cd5b030d7da7

display/d.northarrow/thumbnails/README

@@ -9,15 +9,17 @@ export GRASS_RENDER_WIDTH=300
 export GRASS_RENDER_HEIGHT=300
 g.region raster=elevation
 
-for STYLE in 1a 1b 2 3 4 5 6 7a 7b 8a 8b 9 fancy_compass basic_compass
+#PREFIX=n_arrow_
+PREFIX=""
+
+for STYLE in 1a 1b 2 3 4 5 6 7a 7b 8a 8b 9 fancy_compass basic_compass arrow1 arrow2 arrow3 star
 do
 	echo ${STYLE}
-	export GRASS_RENDER_FILE=n_arrow_${STYLE}.png
-	d.northarrow style=${STYLE} at=20,20
-	mogrify -trim n_arrow_${STYLE}.png
-	identify -format "%[fx:w]x%[fx:h]" n_arrow_${STYLE}.png
-#	convert n_arrow_${STYLE}.png -gravity center -background white -extent 170x24 n_arrow_${STYLE}.png
-	convert n_arrow_${STYLE}.png -gravity center -background white n_arrow_${STYLE}.png
-	optipng -o5 n_arrow_${STYLE}.png n_arrow_${STYLE}.png --quiet
+	export GRASS_RENDER_FILE=${PREFIX}${STYLE}.png
+	d.northarrow -t style=${STYLE} at=20,20
+	mogrify -trim ${PREFIX}${STYLE}.png
+	identify -format "%[fx:w]x%[fx:h]" ${PREFIX}${STYLE}.png
+	# first resize it to max size and then place it into a bigger rectangle
+	mogrify -resize 24x24 -background white -gravity Center -extent 24x24 ${PREFIX}${STYLE}.png
+	optipng -o5 ${PREFIX}${STYLE}.png ${PREFIX}${STYLE}.png --quiet
 done
-

lib/gis/parser_html.c

@@ -256,9 +256,13 @@ void G__usage_html(void)
                             else if (strcmp(opt->gisprompt,
                                             "old,barscale,barscale") == 0)
                                 thumbnails = "barscales";
-                            
+                            else if (strcmp(opt->gisprompt,
+                                            "old,northarrow,northarrow") == 0)
+                                thumbnails = "northarrows";
+
                             if (thumbnails)
-                                fprintf(stdout, "<img width=\"80\" height=\"12\" "
+                                fprintf(stdout, "<img height=\"12\" "
+                                        "style=\"max-width: 80;\""
                                         "src=\"%s/%s.png\" alt=\"%s\"> ",
                                         thumbnails, opt->opts[i], opt->opts[i]);
                         }