tron@2186: /* $Id$ */
tron@2186: 
rubidium@10429: /** @file tile_map.cpp Global tile accessors. */
belugas@6918: 
darkvater@1213: #include "stdafx.h"
rubidium@8604: #include "openttd.h"
rubidium@8604: #include "tile_map.h"
rubidium@8609: #include "core/math_func.hpp"
tron@1211: 
tron@3636: Slope GetTileSlope(TileIndex tile, uint *h)
tron@1335: {
tron@1335: 	uint a;
tron@1335: 	uint b;
tron@1335: 	uint c;
tron@1335: 	uint d;
tron@4067: 	uint min;
tron@4067: 	uint r;
tron@1335: 
tron@1335: 	assert(tile < MapSize());
tron@1335: 
tron@1335: 	if (TileX(tile) == MapMaxX() || TileY(tile) == MapMaxY()) {
tron@1335: 		if (h != NULL) *h = 0;
rubidium@5838: 		return SLOPE_FLAT;
tron@1335: 	}
tron@1335: 
tron@4067: 	min = a = TileHeight(tile);
tron@1981: 	b = TileHeight(tile + TileDiffXY(1, 0));
rubidium@7819: 	if (min > b) min = b;
tron@1981: 	c = TileHeight(tile + TileDiffXY(0, 1));
rubidium@7819: 	if (min > c) min = c;
tron@1981: 	d = TileHeight(tile + TileDiffXY(1, 1));
rubidium@7819: 	if (min > d) min = d;
tron@1335: 
tron@4067: 	r = SLOPE_FLAT;
tron@4067: 	if ((a -= min) != 0) r += (--a << 4) + SLOPE_N;
tron@4067: 	if ((c -= min) != 0) r += (--c << 4) + SLOPE_E;
tron@4067: 	if ((d -= min) != 0) r += (--d << 4) + SLOPE_S;
tron@4067: 	if ((b -= min) != 0) r += (--b << 4) + SLOPE_W;
tron@4067: 
tron@4067: 	if (h != NULL) *h = min * TILE_HEIGHT;
tron@4067: 
rubidium@5838: 	return (Slope)r;
tron@1335: }
tron@1335: 
tron@1335: uint GetTileZ(TileIndex tile)
tron@1335: {
rubidium@7819: 	if (TileX(tile) == MapMaxX() || TileY(tile) == MapMaxY()) return 0;
rubidium@7819: 
rubidium@7819: 	uint h = TileHeight(tile);
rubidium@7819: 	h = min(h, TileHeight(tile + TileDiffXY(1, 0)));
rubidium@7819: 	h = min(h, TileHeight(tile + TileDiffXY(0, 1)));
rubidium@7819: 	h = min(h, TileHeight(tile + TileDiffXY(1, 1)));
rubidium@7819: 
rubidium@7819: 	return h * TILE_HEIGHT;
tron@1335: }
tron@3773: 
tron@3773: 
tron@3773: uint GetTileMaxZ(TileIndex t)
tron@3773: {
rubidium@7820: 	if (TileX(t) == MapMaxX() || TileY(t) == MapMaxY()) return 0;
tron@3773: 
rubidium@7819: 	uint h = TileHeight(t);
rubidium@7819: 	h = max(h, TileHeight(t + TileDiffXY(1, 0)));
rubidium@7819: 	h = max(h, TileHeight(t + TileDiffXY(0, 1)));
rubidium@7819: 	h = max(h, TileHeight(t + TileDiffXY(1, 1)));
rubidium@7819: 
rubidium@7819: 	return h * TILE_HEIGHT;
tron@3773: }