OpenTTD-patches/src/newgrf_canal.cpp

149 lines
4.3 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 newgrf_canal.cpp Implementation of NewGRF canals. */
#include "stdafx.h"
#include "debug.h"
#include "newgrf_spritegroup.h"
#include "newgrf_canal.h"
#include "water_map.h"
/** Table of canal 'feature' sprite groups */
WaterFeature _water_feature[CF_END];
/* Random bits and triggers are not supported for canals, so the following
* three functions are stubs. */
static uint32 CanalGetRandomBits(const ResolverObject *object)
{
/* Return random bits only for water tiles, not station tiles */
return IsTileType(object->u.canal.tile, MP_WATER) ? GetWaterTileRandomBits(object->u.canal.tile) : 0;
}
static uint32 CanalGetTriggers(const ResolverObject *object)
{
return 0;
}
static void CanalSetTriggers(const ResolverObject *object, int triggers)
{
return;
}
static uint32 CanalGetVariable(const ResolverObject *object, byte variable, byte parameter, bool *available)
{
TileIndex tile = object->u.canal.tile;
switch (variable) {
/* Height of tile */
case 0x80: return GetTileZ(tile) / TILE_HEIGHT;
/* Terrain type */
case 0x81: return GetTerrainType(tile);
/* Random data for river or canal tiles, otherwise zero */
case 0x83: return GetWaterTileRandomBits(tile);
}
DEBUG(grf, 1, "Unhandled canal variable 0x%02X", variable);
*available = false;
return UINT_MAX;
}
static const SpriteGroup *CanalResolveReal(const ResolverObject *object, const RealSpriteGroup *group)
{
if (group->num_loaded == 0) return NULL;
return group->loaded[0];
}
static void NewCanalResolver(ResolverObject *res, TileIndex tile, const GRFFile *grffile)
{
res->GetRandomBits = &CanalGetRandomBits;
res->GetTriggers = &CanalGetTriggers;
res->SetTriggers = &CanalSetTriggers;
res->GetVariable = &CanalGetVariable;
res->ResolveReal = &CanalResolveReal;
res->u.canal.tile = tile;
res->callback = CBID_NO_CALLBACK;
res->callback_param1 = 0;
res->callback_param2 = 0;
res->last_value = 0;
res->trigger = 0;
res->reseed = 0;
res->count = 0;
res->grffile = grffile;
}
SpriteID GetCanalSprite(CanalFeature feature, TileIndex tile)
{
ResolverObject object;
const SpriteGroup *group;
NewCanalResolver(&object, tile, _water_feature[feature].grffile);
group = SpriteGroup::Resolve(_water_feature[feature].group, &object);
if (group == NULL) return 0;
return group->GetResult();
}
/**
* Run a specific callback for canals.
* @param callback Callback ID.
* @param param1 Callback parameter 1.
* @param param2 Callback parameter 2.
* @param feature For which feature to run the callback.
* @param tile Tile index of canal.
* @return Callback result or CALLBACK_FAILED if the callback failed.
*/
static uint16 GetCanalCallback(CallbackID callback, uint32 param1, uint32 param2, CanalFeature feature, TileIndex tile)
{
ResolverObject object;
const SpriteGroup *group;
NewCanalResolver(&object, tile, _water_feature[feature].grffile);
object.callback = callback;
object.callback_param1 = param1;
object.callback_param2 = param2;
group = SpriteGroup::Resolve(_water_feature[feature].group, &object);
if (group == NULL) return CALLBACK_FAILED;
return group->GetCallbackResult();
}
/**
* Get the new sprite offset for a water tile.
* @param tile Tile index of the canal/water tile.
* @param feature For which feature to get the new sprite offset.
* @param cur_offset Current sprite offset.
* @return New sprite offset.
*/
uint GetCanalSpriteOffset(CanalFeature feature, TileIndex tile, uint cur_offset)
{
if (HasBit(_water_feature[feature].callback_mask, CBM_CANAL_SPRITE_OFFSET)) {
uint16 cb = GetCanalCallback(CBID_CANALS_SPRITE_OFFSET, cur_offset, 0, feature, tile);
if (cb != CALLBACK_FAILED) return cur_offset + cb;
}
return cur_offset;
}