OpenTTD-patches/src/tile_map.cpp

69 lines
1.5 KiB
C++

/* $Id$ */
/** @file tile_map.cpp Global tile accessors. */
#include "stdafx.h"
#include "openttd.h"
#include "tile_map.h"
#include "core/math_func.hpp"
Slope GetTileSlope(TileIndex tile, uint *h)
{
uint a;
uint b;
uint c;
uint d;
uint min;
uint r;
assert(tile < MapSize());
if (TileX(tile) == MapMaxX() || TileY(tile) == MapMaxY()) {
if (h != NULL) *h = 0;
return SLOPE_FLAT;
}
min = a = TileHeight(tile);
b = TileHeight(tile + TileDiffXY(1, 0));
if (min > b) min = b;
c = TileHeight(tile + TileDiffXY(0, 1));
if (min > c) min = c;
d = TileHeight(tile + TileDiffXY(1, 1));
if (min > d) min = d;
r = SLOPE_FLAT;
if ((a -= min) != 0) r += (--a << 4) + SLOPE_N;
if ((c -= min) != 0) r += (--c << 4) + SLOPE_E;
if ((d -= min) != 0) r += (--d << 4) + SLOPE_S;
if ((b -= min) != 0) r += (--b << 4) + SLOPE_W;
if (h != NULL) *h = min * TILE_HEIGHT;
return (Slope)r;
}
uint GetTileZ(TileIndex tile)
{
if (TileX(tile) == MapMaxX() || TileY(tile) == MapMaxY()) return 0;
uint h = TileHeight(tile);
h = min(h, TileHeight(tile + TileDiffXY(1, 0)));
h = min(h, TileHeight(tile + TileDiffXY(0, 1)));
h = min(h, TileHeight(tile + TileDiffXY(1, 1)));
return h * TILE_HEIGHT;
}
uint GetTileMaxZ(TileIndex t)
{
if (TileX(t) == MapMaxX() || TileY(t) == MapMaxY()) return 0;
uint h = TileHeight(t);
h = max(h, TileHeight(t + TileDiffXY(1, 0)));
h = max(h, TileHeight(t + TileDiffXY(0, 1)));
h = max(h, TileHeight(t + TileDiffXY(1, 1)));
return h * TILE_HEIGHT;
}