better units label placement + adjustable (code) (merge from devbr6)

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@33446 15284696-431f-4ddb-bdfa-cd5b030d7da7

ps/ps.map/ps.map.html

@@ -239,38 +239,42 @@ USAGE:	<B>colortable</B> [y|n]
 </PRE>
 The color table will display the colors for each raster map layer
 category value and the category label.
-If <B>raster</B> is omitted, the colortable defaults to a previously registered raster layer.
+If <B>raster</B> is omitted, the colortable defaults to a previously
+registered raster layer.
 The legend's <B>range</B> can be adjusted for floating point rasters, but if 
 set beyond the extent of the map's range be sure that you have set up color 
 rules with <em>r.colors</em> which cover this range.
 The default location for the colortable is immediately below any other
 map legend information, starting at the left margin.
 The default text color is black.
+
 Omitting the <B>colortable</B> instruction would result in
 no color table. For floating point legends <B>width</B> is width of color
 band only. <B>height</B> is used only for floating point legend.
 Adding the <B>nodata n</B> instruction will prevent the "no data" box 
 from being drawn (category based legends only).
+
 Adding the <B>tickbar y</B> instruction will change the tick mark style
 so that ticks are drawn across the color table instead of protruding out 
 to the right (floating point legends only).
+
+If the map has been given a data units label with r.support then this
+label will be displayed.
+<!-- bonus prize for code explorers: you can switch the label placement by
+    editing the label_posn variable in ps.map/ps_fclrtbl.c -->
 <P> 
-<B>Note</B>:  Be careful about asking for color tables for
+<B>Note</B>:  Be careful about asking for color tables for integer
 raster map layers which have many categories, such as elevation.
 This could result in the printing of an extremely long color table!
 <P>
 Another issue is that the color table only includes categories which
-have a label. If there are only a few categories, you can use
-r.support to manually add labels. If there are too many categories to
-do this, you could write a script to add dummy labels to the cats file<br>
-(&lt;gisdbase&gt;/&lt;location&gt;/&lt;mapset&gt;/cats/&lt;mapname&gt;).
+have a label. You can use the r.category module to add labels.
 <P>
 If the colortable is turned off with a &quot;<tt>colortable&nbsp;n</tt>&quot;
 instruction the <B>end</B> command should not be given as the  
 main command will be treated as a single line instruction.
 
 <P>
-
 This example would print a color table immediately below any other map legend
 information, starting at the left margin, with 4 columns:
 <PRE>
@@ -1157,7 +1161,8 @@ the text box <B>border</B> color;
 This reference point specifies the text handle - what
 part of the text should be placed on the location specified by the map
 coordinates.  Reference points can refer to:
-[lower|upper|center] [left|right|center] of the text to be printed; The default is center center, i.e the text is centered on the reference point.
+[lower|upper|center] [left|right|center] of the text to be printed;
+The default is center center, i.e the text is centered on the reference point.
 <P>
 <B>rotate</B>
 sets the text rotation angle, measured in degrees counter-clockwise.
@@ -1256,8 +1261,8 @@ first vector is used.
 simple PostScript commands. It is similar to EPS but more limited, meaning that
 while each pattern file is a true EPS file, most EPS files are not useful as pattern
 files because they contain restricted commands. Color and width of patterns are set
-by <B>fcolor</B> (red, green, ..., none, R:G:B) and <B>width</B> until overwritten
-in the pattern file.
+by <B>fcolor</B> (red, green, ..., none, R:G:B) and <B>width</B> until
+overwritten in the pattern file.
 Pattern may be scaled with the <b>scale</b> command. Several standard hatching
 patterns are provided in <tt>$GISBASE/etc/paint/patterns/</tt>.
 Demonstrative images can be found on the

ps/ps.map/ps_fclrtbl.c

@@ -26,7 +26,7 @@ int PS_fcolortable(void)
     int R, G, B;
     DCELL dmin, dmax, val;
     double t, l, r;		/* legend top, left, right */
-    double x1, x2, y, dy, fontsize;
+    double x1, x2, y, dy, fontsize, xu, yu;
     double col_width;
     double width;		/* width of legend in map units */
     double height;		/* width of legend in map units */
@@ -40,7 +40,7 @@ int PS_fcolortable(void)
     double ex, cur_d, cur_ex;
     int do_color;
     double grey_color_val, margin;
-    int max_label_length = 0;
+    int max_label_length = 0, label_posn, label_xref, label_yref;
 
     /* let user know what's happenning */
     G_message(_("Creating color table for <%s in %s>..."),
@@ -251,17 +251,66 @@ int PS_fcolortable(void)
     if (G_read_raster_units(ct.name, ct.mapset, units) != 0)
         units[0] = '\0';
 
-    /* TODO: nicer placement as label length changes; realign for tickbar mode */
     if(strlen(units)) {
 	margin = 0.2 * fontsize;
 	if (margin < 2)
 	    margin = 2;
 	fprintf(PS.fp, "/mg %.1f def\n", margin);
 
-	text_box_path( x2 + max_label_length*(fontsize*.7),
-		t - height/2,
-	        LEFT, CENTER, units, fontsize, 0);
+	/* select label position */
+	label_posn = 3;
+	/*  1 2
+	       3
+	     5 4 */
+	switch (label_posn) {
+	case 1:
+	    /* above the tick numbers */
+	    xu = x1;
+	    yu = t + 0.05*72;
+	    label_xref = LEFT;
+	    label_yref = LOWER;
+	    break;
+	case 2:
+	    /* directly above the tick numbers */
+	    if (ct.tickbar)
+		xu += x1 + 0.2 * fontsize;
+	    else
+		xu += x2 + 0.2 * fontsize;
+	    yu = t + 0.05*72;
+	    label_xref = LEFT;
+	    label_yref = LOWER;
+	    break;
+	case 3:
+	    /* to the right of the tick numbers */
+	    xu = 0.15*72 + max_label_length*fontsize*0.5;
+	    if (ct.tickbar)
+		xu += x1;
+	    else
+		xu += x2;
+	    yu = t - height/2;
+	    label_xref = LEFT;
+	    label_yref = CENTER;
+	    break;
+	case 4:
+	    /* directly below the tick numbers */
+	    if (ct.tickbar)
+		xu += x1 + 0.2 * fontsize;
+	    else
+		xu += x2 + 0.2 * fontsize;
+	    yu = t - height - 0.05*72;
+	    label_xref = LEFT;
+	    label_yref = UPPER;
+	    break;
+	case 5:
+	    /* below the tick numbers */
+	    xu = x1;
+	    yu = t - height - 0.05*72;
+	    label_xref = LEFT;
+	    label_yref = UPPER;
+	    break;
+	}
 
+	text_box_path( xu, yu, label_xref, label_yref, units, fontsize, 0);
 	set_rgb_color(BLACK); 
 	fprintf(PS.fp, "TIB\n");
     }