Add margin as an option that be specified as a percentage or in degrees.

diff --git a/gpsbabel/tiger.c b/gpsbabel/tiger.c
index 17c829b8078e00c0db52e80f3317a68a81b232de..2b026590984365439a8fc50916b603dca199094b 100644 (file)
--- a/gpsbabel/tiger.c
+++ b/gpsbabel/tiger.c
@@ -37,6 +37,7 @@ static char *nolabels = NULL;
 static char *genurl = NULL;
 static char *scale = "768";
 static char *snlen = NULL;
+static char *margin  = "15%";
 int scalev;
 int short_length;
 
@@ -56,6 +57,8 @@ arglist_t tiger_args[] = {
                ARGTYPE_BOOL },
        {"genurl", &genurl, "Generate file with lat/lon for centering map.",
                ARGTYPE_OUTFILE },
+       {"margin", &margin, "Margin for map.  Degrees or percentage.",
+               ARGTYPE_FLOAT},
        {"scale", &scale, "Dimension in pixels of map.",
                ARGTYPE_INT},
        {"snlen", &snlen, "Max shortname length when used with -s.",
@@ -168,6 +171,23 @@ map_plot(const waypoint *wpt)
        fprintf(linkf, "<area shape=\"circle\" coords=\"%d,%d,7\" href=\"%s\" alt=\"%s\"\n", x, y, wpt->url, wpt->description);
 }
 
+static double
+dscale(double distance)
+{
+       /*
+        * If we have any specified margin options  factor those in now.  
+        * A additional little boundary is helpful becuase Tiger always 
+        * puts the pin above the actual coord and if we don't pad the 
+        * top will be clipped.   It also makes the maps more useful to 
+        * have a little bit of context around the pins on the border.
+        */
+
+       if (strchr(margin, '%'))
+               return distance + strtod(margin, NULL) / 100.0 * distance;
+       else
+               return strtod(margin, NULL) + distance;
+}
+
 static void
 data_write(void)
 {
@@ -201,18 +221,13 @@ data_write(void)
 
                /*
                 * Center the map along X and Y axis the midpoint of
-                * our min and max coords each way.   Size it with an 
-                * additional little boundary becuase Tiger always puts
-                * the pin above the actual coord and if we don't pad
-                * the top will be clipped.   It also makes the maps 
-                * more useful to have a little bit of context around
-                * the pins on the border.
+                * our min and max coords each way.   
                 */
                fprintf(urlf, "lat=%f&lon=%f&wid=%f&ht=%f",
                                minlat + (latsz/2.0),
                                minlon + (lonsz/2.0),
-                               latsz * 1.15,
-                               latsz * 1.15);
+                               dscale(latsz),
+                               dscale(latsz));
 
                if (scale) {
                        fprintf(urlf, "&iwd=%s&iht=%s", scale, scale);