--- a/src/smallmap_gui.cpp	Mon May 05 12:35:38 2008 +0000
+++ b/src/smallmap_gui.cpp	Wed May 07 21:09:51 2008 +0000
@@ -1,6 +1,6 @@
 /* $Id$ */
 
-/** @file smallmap_gui.cpp */
+/** @file smallmap_gui.cpp GUI that shows a small map of the world with metadata like owner or height. */
 
 #include "stdafx.h"
 #include "openttd.h"
@@ -27,6 +27,7 @@
 #include "vehicle_base.h"
 #include "sound_func.h"
 #include "settings_type.h"
+#include "window_func.h"
 
 #include "table/strings.h"
 #include "table/sprites.h"
@@ -785,7 +786,7 @@
 	y  = ((vp->virtual_height - (w->widget[SM_WIDGET_MAP].bottom - w->widget[SM_WIDGET_MAP].top ) * TILE_SIZE) / 2 + vp->virtual_top ) / 2 - TILE_SIZE * 2;
 	WP(w, smallmap_d).scroll_x = (y - x) & ~0xF;
 	WP(w, smallmap_d).scroll_y = (x + y) & ~0xF;
-	SetWindowDirty(w);
+	w->SetDirty();
 }
 
 enum {
@@ -879,7 +880,7 @@
 					WP(w2, vp_d).dest_scrollpos_x = pt.x + ((_cursor.pos.x - w->left + 2) << 4) - (w2->viewport->virtual_width >> 1);
 					WP(w2, vp_d).dest_scrollpos_y = pt.y + ((_cursor.pos.y - w->top - 16) << 4) - (w2->viewport->virtual_height >> 1);
 
-					SetWindowDirty(w);
+					w->SetDirty();
 				} break;
 
 				case SM_WIDGET_CONTOUR:    // Show land contours
@@ -892,14 +893,14 @@
 					_smallmap_type = e->we.click.widget - SM_WIDGET_CONTOUR;
 					w->LowerWidget(_smallmap_type + SM_WIDGET_CONTOUR);
 
-					SetWindowDirty(w);
+					w->SetDirty();
 					SndPlayFx(SND_15_BEEP);
 					break;
 
 				case SM_WIDGET_CENTERMAP: // Center the smallmap again
 					SmallMapCenterOnCurrentPos(w);
 
-					SetWindowDirty(w);
+					w->SetDirty();
 					SndPlayFx(SND_15_BEEP);
 					break;
 
@@ -907,7 +908,7 @@
 					w->ToggleWidgetLoweredState(SM_WIDGET_TOGGLETOWNNAME);
 					_smallmap_show_towns = w->IsWidgetLowered(SM_WIDGET_TOGGLETOWNNAME);
 
-					SetWindowDirty(w);
+					w->SetDirty();
 					SndPlayFx(SND_15_BEEP);
 					break;
 
@@ -939,7 +940,7 @@
 						/* Raise the two buttons "all", as we have done a specific choice */
 						w->RaiseWidget(SM_WIDGET_ENABLEINDUSTRIES);
 						w->RaiseWidget(SM_WIDGET_DISABLEINDUSTRIES);
-						SetWindowDirty(w);
+						w->SetDirty();
 					}
 					break;
 
@@ -950,7 +951,7 @@
 					/* toggle appeareance indicating the choice */
 					w->LowerWidget(SM_WIDGET_ENABLEINDUSTRIES);
 					w->RaiseWidget(SM_WIDGET_DISABLEINDUSTRIES);
-					SetWindowDirty(w);
+					w->SetDirty();
 					break;
 
 				case SM_WIDGET_DISABLEINDUSTRIES: // disable all industries
@@ -960,7 +961,7 @@
 					/* toggle appeareance indicating the choice */
 					w->RaiseWidget(SM_WIDGET_ENABLEINDUSTRIES);
 					w->LowerWidget(SM_WIDGET_DISABLEINDUSTRIES);
-					SetWindowDirty(w);
+					w->SetDirty();
 					break;
 				}
 			break;
@@ -976,7 +977,7 @@
 
 		case WE_MOUSELOOP:
 			/* update the window every now and then */
-			if ((++w->vscroll.pos & 0x1F) == 0) SetWindowDirty(w);
+			if ((++w->vscroll.pos & 0x1F) == 0) w->SetDirty();
 			break;
 
 		case WE_SCROLL: {
@@ -1037,7 +1038,7 @@
 			WP(w, smallmap_d).scroll_y = y;
 			WP(w, smallmap_d).subscroll = sub;
 
-			SetWindowDirty(w);
+			w->SetDirty();
 		} break;
 	}
 }
@@ -1191,25 +1192,30 @@
 	ExtraViewPortWndProc
 };
 
-void ShowExtraViewPortWindow()
+void ShowExtraViewPortWindow(TileIndex tile)
 {
-	Window *w, *v;
 	int i = 0;
 
 	/* find next free window number for extra viewport */
 	while (FindWindowById(WC_EXTRA_VIEW_PORT, i) != NULL) i++;
 
-	w = AllocateWindowDescFront(&_extra_view_port_desc, i);
+	Window *w = AllocateWindowDescFront(&_extra_view_port_desc, i);
 	if (w != NULL) {
-		int x, y;
-		/* the main window with the main view */
-		v = FindWindowById(WC_MAIN_WINDOW, 0);
+		Point pt;
 
-		/* center on same place as main window (zoom is maximum, no adjustment needed) */
-		x = WP(v, vp_d).scrollpos_x;
-		y = WP(v, vp_d).scrollpos_y;
-		WP(w, vp_d).scrollpos_x = x + (v->viewport->virtual_width  - (w->widget[4].right - w->widget[4].left) - 1) / 2;
-		WP(w, vp_d).scrollpos_y = y + (v->viewport->virtual_height - (w->widget[4].bottom - w->widget[4].top) - 1) / 2;
+		if (tile == INVALID_TILE) {
+			/* the main window with the main view */
+			const Window *v = FindWindowById(WC_MAIN_WINDOW, 0);
+
+			/* center on same place as main window (zoom is maximum, no adjustment needed) */
+			pt.x = WP(v, vp_d).scrollpos_x + v->viewport->virtual_height / 2;
+			pt.y = WP(v, vp_d).scrollpos_y + v->viewport->virtual_height / 2;
+		} else {
+			pt = RemapCoords(TileX(tile) * TILE_SIZE + TILE_SIZE / 2, TileY(tile) * TILE_SIZE + TILE_SIZE / 2, TileHeight(tile));
+		}
+
+		WP(w, vp_d).scrollpos_x = pt.x - ((w->widget[4].right - w->widget[4].left) - 1) / 2;
+		WP(w, vp_d).scrollpos_y = pt.y - ((w->widget[4].bottom - w->widget[4].top) - 1) / 2;
 		WP(w, vp_d).dest_scrollpos_x = WP(w, vp_d).scrollpos_x;
 		WP(w, vp_d).dest_scrollpos_y = WP(w, vp_d).scrollpos_y;
 	}