merging my updates, since they are already implemented in 1.5.1

--HG--
branch : openttd

src/town_cmd.cpp

@@ -377,7 +377,8 @@ void Town::UpdateVirtCoord()
 	SetDParam(0, this->index);
 	SetDParam(1, this->cache.population);
 	this->cache.sign.UpdatePosition(pt.x, pt.y - 24 * ZOOM_LVL_BASE,
-		_settings_client.gui.population_in_label ? STR_VIEWPORT_TOWN_POP : STR_VIEWPORT_TOWN);
+		_settings_client.gui.population_in_label ? STR_VIEWPORT_TOWN_POP : STR_VIEWPORT_TOWN,
+		STR_VIEWPORT_TOWN);
 
 	SetWindowDirty(WC_TOWN_VIEW, this->index);
 }

src/viewport.cpp

@@ -1310,7 +1310,7 @@ static void ViewportAddSigns(DrawPixelInfo *dpi)
  * @param top    the new top of the sign
  * @param str    the string to show in the sign
  */
-void ViewportSign::UpdatePosition(int center, int top, StringID str)
+void ViewportSign::UpdatePosition(int center, int top, StringID str, StringID small_str)
 {
 	if (this->width_normal != 0) this->MarkDirty();
 
@@ -1323,6 +1323,9 @@ void ViewportSign::UpdatePosition(int center, int top, StringID str)
 	this->center = center;
 
 	/* zoomed out version */
+	if (small_str != STR_NULL) {
+		GetString(buffer, small_str, lastof(buffer));
+	}
 	this->width_small = VPSM_LEFT + Align(GetStringBoundingBox(buffer, FS_SMALL).width, 2) + VPSM_RIGHT;
 
 	this->MarkDirty();

src/viewport_type.h

@@ -14,6 +14,7 @@
 
 #include "zoom_type.h"
 #include "strings_type.h"
+#include "table/strings.h"
 
 class LinkGraphOverlay;
 
@@ -50,7 +51,7 @@ struct ViewportSign {
 	uint16 width_normal; ///< The width when not zoomed out (normal font)
 	uint16 width_small;  ///< The width when zoomed out (small font)
 
-	void UpdatePosition(int center, int top, StringID str);
+	void UpdatePosition(int center, int top, StringID str, StringID small_str=STR_NULL);
 	void MarkDirty(ZoomLevel maxzoom = ZOOM_LVL_MAX) const;
 };