OpenTTD-patches/src/bridge_map.cpp
2018-10-31 12:35:54 +01:00

81 lines
2.3 KiB
C++

/* $Id$ */
/*
* This file is part of OpenTTD.
* OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
* OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
*/
/** @file bridge_map.cpp Map accessor functions for bridges. */
#include "stdafx.h"
#include "landscape.h"
#include "tunnelbridge_map.h"
#include "safeguards.h"
/**
* Finds the end of a bridge in the specified direction starting at a middle tile
* @param tile the bridge tile to find the bridge ramp for
* @param dir the direction to search in
*/
static TileIndex GetBridgeEnd(TileIndex tile, DiagDirection dir)
{
TileIndexDiff delta = TileOffsByDiagDir(dir);
dir = ReverseDiagDir(dir);
do {
tile += delta;
} while (!IsBridgeTile(tile) || GetTunnelBridgeDirection(tile) != dir);
return tile;
}
/**
* Finds the northern end of a bridge starting at a middle tile
* @param t the bridge tile to find the bridge ramp for
*/
TileIndex GetNorthernBridgeEnd(TileIndex t)
{
return GetBridgeEnd(t, ReverseDiagDir(AxisToDiagDir(GetBridgeAxis(t))));
}
/**
* Finds the southern end of a bridge starting at a middle tile
* @param t the bridge tile to find the bridge ramp for
*/
TileIndex GetSouthernBridgeEnd(TileIndex t)
{
return GetBridgeEnd(t, AxisToDiagDir(GetBridgeAxis(t)));
}
/**
* Starting at one bridge end finds the other bridge end
* @param tile the bridge ramp tile to find the other bridge ramp for
*/
TileIndex GetOtherBridgeEnd(TileIndex tile)
{
assert(IsBridgeTile(tile));
return GetBridgeEnd(tile, GetTunnelBridgeDirection(tile));
}
/**
* Get the height ('z') of a bridge.
* @param t the bridge ramp tile to get the bridge height from
* @return the height of the bridge.
*/
int GetBridgeHeight(TileIndex t)
{
int h;
Slope tileh = GetTileSlope(t, &h);
Foundation f = GetBridgeFoundation(tileh, DiagDirToAxis(GetTunnelBridgeDirection(t)));
/* one height level extra for the ramp */
return h + 1 + ApplyFoundationToSlope(f, &tileh);
}