(svn r3726) - [6/6] Finalize conversion, finally save the patches struct.
- Remove the temporary synchronisation in during the map-transfer as this is no longer needed
- The saved patches work just like the saved gameoptions. You have a _patches and a _patches_newgame struct. The _patches_newgame struct contains the values from the configuration file and thus the defaults for new games. When a new game is started or an older game is loaded, the default values are copied over to _patches to be used. When you load a game that has PATS saved, the default values are also loaded, but immediately overwritten by the values from the savegame. This ensures that player-based values are always taken from your personal preferences.
- The current implementation also changes the default values if you change player-based settings in the game. For example changing window_snap_radius in a certain game will also change it for all next OpenTTD sessions.
- The savegame version has been increased to 22.
- The last 6 orso patches close the following reports:
[ 1366446 ] different names for patches: all patch settings have the same name as in the configuration file and are reachable from the console.
[ 1288024 ] Strange string on OTTD initial screen: configuration (and this includes patches) inputs are validated and clamped to their minimum/maximum values.
[ 1423198 ] Make "Signals on Drive side" player, not server, based: this is only visual so current setting is to save it with the savegame but not synchronise in multiplayer.
[ 1208070 ] Patches and New GRF options saved: apart from newgrf this is done

/* $Id$ */

#include "stdafx.h"
#include "tile.h"

void SetMapExtraBits(TileIndex tile, byte bits)
{
	assert(tile < MapSize());
	SB(_m[tile].extra, 0, 2, bits & 3);
}

uint GetMapExtraBits(TileIndex tile)
{
	assert(tile < MapSize());
	return GB(_m[tile].extra, 0, 2);
}


uint 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 0;
	}

	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 = 0;
	if ((a -= min) != 0) r += (--a << 4) + 8;
	if ((c -= min) != 0) r += (--c << 4) + 4;
	if ((d -= min) != 0) r += (--d << 4) + 2;
	if ((b -= min) != 0) r += (--b << 4) + 1;

	if (h != NULL) *h = min * 8;

	return r;
}

uint GetTileZ(TileIndex tile)
{
	uint h;
	GetTileSlope(tile, &h);
	return h;
}