(svn r15725) -Fix: centering on a vehicle didn't respect its z coordinate

src/main_gui.cpp

@@ -176,7 +176,7 @@ void ZoomInOrOutToCursorWindow(bool in, Window *w)
 
 		Point pt = GetTileZoomCenterWindow(in, w);
 		if (pt.x != -1) {
-			ScrollWindowTo(pt.x, pt.y, w, true);
+			ScrollWindowTo(pt.x, pt.y, -1, w, true);
 
 			DoZoomInOutWindow(in ? ZOOM_IN : ZOOM_OUT, w);
 		}

src/news_gui.cpp

@@ -267,8 +267,8 @@ struct NewsWindow : Window {
 
 			case 0:
 				if (this->ni->flags & NF_VEHICLE) {
-					Vehicle *v = GetVehicle(this->ni->data_a);
-					ScrollMainWindowTo(v->x_pos, v->y_pos);
+					const Vehicle *v = GetVehicle(this->ni->data_a);
+					ScrollMainWindowTo(v->x_pos, v->y_pos, v->z_pos);
 				} else if (this->ni->flags & NF_TILE) {
 					if (_ctrl_pressed) {
 						ShowExtraViewPortWindow(this->ni->data_a);

src/smallmap_gui.cpp

@@ -1214,9 +1214,17 @@ void ShowExtraViewPortWindow(TileIndex tile)
 	new ExtraViewportWindow(&_extra_view_port_desc, i, tile);
 }
 
-bool ScrollMainWindowTo(int x, int y, bool instant)
+/**
+ * Scrolls the main window to given coordinates.
+ * @param x x coordinate
+ * @param y y coordinate
+ * @param z z coordinate; -1 to scroll to terrain height
+ * @param instant scroll instantly (meaningful only when smooth_scrolling is active)
+ * @return did the viewport position change?
+ */
+bool ScrollMainWindowTo(int x, int y, int z, bool instant)
 {
-	bool res = ScrollWindowTo(x, y, FindWindowById(WC_MAIN_WINDOW, 0), instant);
+	bool res = ScrollWindowTo(x, y, z, FindWindowById(WC_MAIN_WINDOW, 0), instant);
 
 	/* If a user scrolls to a tile (via what way what so ever) and already is on
 	 *  that tile (e.g.: pressed twice), move the smallmap to that location,

src/vehicle_gui.cpp

@@ -1957,7 +1957,7 @@ struct VehicleViewWindow : Window {
 				if (_ctrl_pressed && mainwindow->viewport->zoom == ZOOM_LVL_NORMAL) {
 					mainwindow->viewport->follow_vehicle = v->index;
 				} else {
-					ScrollMainWindowTo(v->x_pos, v->y_pos);
+					ScrollMainWindowTo(v->x_pos, v->y_pos, v->z_pos);
 				}
 			} break;
 
@@ -2037,7 +2037,7 @@ void StopGlobalFollowVehicle(const Vehicle *v)
 {
 	Window *w = FindWindowById(WC_MAIN_WINDOW, 0);
 	if (w != NULL && w->viewport->follow_vehicle == v->index) {
-		ScrollMainWindowTo(v->x_pos, v->y_pos, true); // lock the main view on the vehicle's last position
+		ScrollMainWindowTo(v->x_pos, v->y_pos, v->z_pos, true); // lock the main view on the vehicle's last position
 		w->viewport->follow_vehicle = INVALID_VEHICLE;
 	}
 }

src/viewport.cpp

@@ -137,7 +137,7 @@ TileHighlightData _thd;
 static TileInfo *_cur_ti;
 bool _draw_bounding_boxes = false;
 
-static Point MapXYZToViewport(const ViewPort *vp, uint x, uint y, uint z)
+static Point MapXYZToViewport(const ViewPort *vp, int x, int y, int z)
 {
 	Point p = RemapCoords(x, y, z);
 	p.x -= vp->virtual_width / 2;
@@ -2065,10 +2065,12 @@ void PlaceObject()
 
 
 /* scrolls the viewport in a window to a given location */
-bool ScrollWindowTo(int x , int y, Window *w, bool instant)
+bool ScrollWindowTo(int x, int y, int z, Window *w, bool instant)
 {
 	/* The slope cannot be acquired outside of the map, so make sure we are always within the map. */
-	Point pt = MapXYZToViewport(w->viewport, x, y, GetSlopeZ(Clamp(x, 0, MapSizeX() * TILE_SIZE - 1), Clamp(y, 0, MapSizeY() * TILE_SIZE - 1)));
+	if (z == -1) z = GetSlopeZ(Clamp(x, 0, MapSizeX() * TILE_SIZE - 1), Clamp(y, 0, MapSizeY() * TILE_SIZE - 1));
+
+	Point pt = MapXYZToViewport(w->viewport, x, y, z);
 	w->viewport->follow_vehicle = INVALID_VEHICLE;
 
 	if (w->viewport->dest_scrollpos_x == pt.x && w->viewport->dest_scrollpos_y == pt.y)
@@ -2086,7 +2088,7 @@ bool ScrollWindowTo(int x , int y, Window *w, bool instant)
 
 bool ScrollMainWindowToTile(TileIndex tile, bool instant)
 {
-	return ScrollMainWindowTo(TileX(tile) * TILE_SIZE + TILE_SIZE / 2, TileY(tile) * TILE_SIZE + TILE_SIZE / 2, instant);
+	return ScrollMainWindowTo(TileX(tile) * TILE_SIZE + TILE_SIZE / 2, TileY(tile) * TILE_SIZE + TILE_SIZE / 2, -1, instant);
 }
 
 void SetRedErrorSquare(TileIndex tile)

src/viewport_func.h

@@ -53,10 +53,10 @@ Vehicle *CheckMouseOverVehicle();
 
 void ViewportDoDraw(const ViewPort *vp, int left, int top, int right, int bottom);
 
-bool ScrollWindowTo(int x, int y, Window *w, bool instant = false);
+bool ScrollWindowTo(int x, int y, int z, Window *w, bool instant = false);
 
 bool ScrollMainWindowToTile(TileIndex tile, bool instant = false);
-bool ScrollMainWindowTo(int x, int y, bool instant = false);
+bool ScrollMainWindowTo(int x, int y, int z = -1, bool instant = false);
 
 extern Point _tile_fract_coords;
 

src/waypoint_gui.cpp

@@ -87,7 +87,7 @@ public:
 	{
 		int x = TileX(this->wp->xy) * TILE_SIZE;
 		int y = TileY(this->wp->xy) * TILE_SIZE;
-		ScrollWindowTo(x, y, this);
+		ScrollWindowTo(x, y, -1, this);
 	}
 
 	virtual void OnQueryTextFinished(char *str)

src/window.cpp

@@ -1651,7 +1651,7 @@ static bool HandleViewportScroll()
 	if (w == FindWindowById(WC_MAIN_WINDOW, 0) && w->viewport->follow_vehicle != INVALID_VEHICLE) {
 		/* If the main window is following a vehicle, then first let go of it! */
 		const Vehicle *veh = GetVehicle(w->viewport->follow_vehicle);
-		ScrollMainWindowTo(veh->x_pos, veh->y_pos, true); // This also resets follow_vehicle
+		ScrollMainWindowTo(veh->x_pos, veh->y_pos, veh->z_pos, true); // This also resets follow_vehicle
 		return true;
 	}