add a reload_map member function...

...that allows the display object to stay in sync when the map
dimensions have changed

src/builder.cpp

@@ -119,6 +119,13 @@ void terrain_builder::tilemap::reset()
 		it->clear();
 }
 
+void terrain_builder::tilemap::reload(int x, int y)
+{
+	x_ = x;
+	y_ = y;
+	map_.resize((x + 4) * (y + 4));
+}
+
 bool terrain_builder::tilemap::on_map(const gamemap::location &loc) const
 {
 	if(loc.x < -2 || loc.y < -2 || loc.x > (x_ + 1) || loc.y > (y_ + 1)) {
@@ -162,6 +169,13 @@ terrain_builder::terrain_builder(const config& cfg, const config& level,
 	build_terrains();
 }
 
+void terrain_builder::reload_map()
+{
+	tile_map_.reload(map_.w(), map_.h());
+	terrain_by_type_.clear();
+	build_terrains();
+}
+
 const terrain_builder::imagelist *terrain_builder::get_terrain_at(const gamemap::location &loc,
 		const std::string &tod, const ADJACENT_TERRAIN_TYPE terrain_type)
 {

src/builder.hpp

@@ -76,6 +76,12 @@ public:
 	 */
 	terrain_builder(const config& cfg, const config &level,
 		const gamemap& map, const std::string& offmap_image);
+		
+	/** 
+	 * Updates internals that cache map size. This should be called when the map 
+	 * size has changed.
+	 */
+	void reload_map();
 
 	/** Returns a vector of strings representing the images to load & blit
 	 * together to get the built content for this tile.
@@ -387,6 +393,11 @@ private:
 		 * Resets the whole tile map
 		 */
 		void reset();
+		
+		/**
+		 * Rebuilds the map to a new set of dimensions
+		 */
+		void reload(int x, int y);
 	private:
 		/** The map */
 		std::vector<tile> map_;

src/display.cpp

@@ -79,8 +79,7 @@ display::display(CVideo& video, const gamemap& map, const config& theme_cfg, con
 	viewpoint_(NULL), 
 	xpos_(0), 
 	ypos_(0),
-	theme_(theme_cfg,
-	screen_area()),
+	theme_(theme_cfg, screen_area()),
 	zoom_(DefaultZoom), 
 	last_zoom_(SmallZoom),
 	builder_(cfg, level, map, theme_.border().tile_image),
@@ -139,6 +138,15 @@ display::~display()
 {
 }
 
+void display::reload_map()
+{
+	builder_.reload_map();
+	SDL_Rect m = map_area();
+	if (!hex_clicked_on(m.x + m.w, m.y + m.h).valid()) {
+		scroll_to_tile(gamemap::location(0, 0), WARP);
+	}
+}
+
 const SDL_Rect& display::max_map_area() const
 {
 	static SDL_Rect max_area = {0, 0, 0, 0};

src/display.hpp

@@ -64,6 +64,12 @@ public:
 	display(CVideo& video, const gamemap& map, const config& theme_cfg,
 			const config& cfg, const config& level);
 	virtual ~display();
+	
+	/** 
+	 * Updates internals that cache map size. This should be called when the map 
+	 * size has changed.
+	 */
+	void reload_map();
 
 	static Uint32 rgb(Uint8 red, Uint8 green, Uint8 blue)
 		{ return 0xFF000000 | (red << 16) | (green << 8) | blue; }