1

/* $Id$ */

     2

     3

/** @file tile.cpp */

     4

     5

#include "stdafx.h"

     6

#include "tile.h"

     7

     8

Slope GetTileSlope(TileIndex tile, uint *h)

     9

{

    10

	uint a;

    11

	uint b;

    12

	uint c;

    13

	uint d;

    14

	uint min;

    15

	uint r;

    16

    17

	assert(tile < MapSize());

    18

    19

	if (TileX(tile) == MapMaxX() || TileY(tile) == MapMaxY()) {

    20

		if (h != NULL) *h = 0;

    21

		return SLOPE_FLAT;

    22

	}

    23

    24

	min = a = TileHeight(tile);

    25

	b = TileHeight(tile + TileDiffXY(1, 0));

    26

	if (min >= b) min = b;

    27

	c = TileHeight(tile + TileDiffXY(0, 1));

    28

	if (min >= c) min = c;

    29

	d = TileHeight(tile + TileDiffXY(1, 1));

    30

	if (min >= d) min = d;

    31

    32

	r = SLOPE_FLAT;

    33

	if ((a -= min) != 0) r += (--a << 4) + SLOPE_N;

    34

	if ((c -= min) != 0) r += (--c << 4) + SLOPE_E;

    35

	if ((d -= min) != 0) r += (--d << 4) + SLOPE_S;

    36

	if ((b -= min) != 0) r += (--b << 4) + SLOPE_W;

    37

    38

	if (h != NULL) *h = min * TILE_HEIGHT;

    39

    40

	return (Slope)r;

    41

}

    42

    43

uint GetTileZ(TileIndex tile)

    44

{

    45

	uint h;

    46

	GetTileSlope(tile, &h);

    47

	return h;

    48

}

    49

    50

    51

uint GetTileMaxZ(TileIndex t)

    52

{

    53

	uint max;

    54

	uint h;

    55

    56

	h = TileHeight(t);

    57

	max = h;

    58

	h = TileHeight(t + TileDiffXY(1, 0));

    59

	if (h > max) max = h;

    60

	h = TileHeight(t + TileDiffXY(0, 1));

    61

	if (h > max) max = h;

    62

	h = TileHeight(t + TileDiffXY(1, 1));

    63

	if (h > max) max = h;

    64

	return max * 8;

    65

}