/* * 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 . */ /** * @file slope_type.h Definitions of a slope. * This file defines the enumeration and helper functions for handling * the slope info of a tile. */ #ifndef SLOPE_TYPE_H #define SLOPE_TYPE_H #include "core/enum_type.hpp" /** * Enumeration of tile corners */ enum Corner { CORNER_W = 0, CORNER_S = 1, CORNER_E = 2, CORNER_N = 3, CORNER_END, CORNER_INVALID = 0xFF }; /** * Enumeration for the slope-type. * * This enumeration use the chars N,E,S,W corresponding the * direction north, east, south and west. The top corner of a tile * is the north-part of the tile. The whole slope is encoded with * 5 bits, 4 bits for each corner and 1 bit for a steep-flag. * * For halftile slopes an extra 3 bits are used to represent this * properly; 1 bit for a halftile-flag and 2 bits to encode which * extra side (corner) is leveled when the slope of the first 5 * bits is applied. This means that there can only be one leveled * slope for steep slopes, which is logical because two leveled * slopes would mean that it is not a steep slope as halftile * slopes only span one height level. */ enum Slope : uint8_t { SLOPE_FLAT = 0x00, ///< a flat tile SLOPE_W = 0x01, ///< the west corner of the tile is raised SLOPE_S = 0x02, ///< the south corner of the tile is raised SLOPE_E = 0x04, ///< the east corner of the tile is raised SLOPE_N = 0x08, ///< the north corner of the tile is raised SLOPE_STEEP = 0x10, ///< indicates the slope is steep SLOPE_NW = SLOPE_N | SLOPE_W, ///< north and west corner are raised SLOPE_SW = SLOPE_S | SLOPE_W, ///< south and west corner are raised SLOPE_SE = SLOPE_S | SLOPE_E, ///< south and east corner are raised SLOPE_NE = SLOPE_N | SLOPE_E, ///< north and east corner are raised SLOPE_EW = SLOPE_E | SLOPE_W, ///< east and west corner are raised SLOPE_NS = SLOPE_N | SLOPE_S, ///< north and south corner are raised SLOPE_ELEVATED = SLOPE_N | SLOPE_E | SLOPE_S | SLOPE_W, ///< bit mask containing all 'simple' slopes SLOPE_NWS = SLOPE_N | SLOPE_W | SLOPE_S, ///< north, west and south corner are raised SLOPE_WSE = SLOPE_W | SLOPE_S | SLOPE_E, ///< west, south and east corner are raised SLOPE_SEN = SLOPE_S | SLOPE_E | SLOPE_N, ///< south, east and north corner are raised SLOPE_ENW = SLOPE_E | SLOPE_N | SLOPE_W, ///< east, north and west corner are raised SLOPE_STEEP_W = SLOPE_STEEP | SLOPE_NWS, ///< a steep slope falling to east (from west) SLOPE_STEEP_S = SLOPE_STEEP | SLOPE_WSE, ///< a steep slope falling to north (from south) SLOPE_STEEP_E = SLOPE_STEEP | SLOPE_SEN, ///< a steep slope falling to west (from east) SLOPE_STEEP_N = SLOPE_STEEP | SLOPE_ENW, ///< a steep slope falling to south (from north) SLOPE_HALFTILE = 0x20, ///< one halftile is leveled (non continuous slope) SLOPE_HALFTILE_MASK = 0xE0, ///< three bits used for halftile slopes SLOPE_HALFTILE_W = SLOPE_HALFTILE | (CORNER_W << 6), ///< the west halftile is leveled (non continuous slope) SLOPE_HALFTILE_S = SLOPE_HALFTILE | (CORNER_S << 6), ///< the south halftile is leveled (non continuous slope) SLOPE_HALFTILE_E = SLOPE_HALFTILE | (CORNER_E << 6), ///< the east halftile is leveled (non continuous slope) SLOPE_HALFTILE_N = SLOPE_HALFTILE | (CORNER_N << 6), ///< the north halftile is leveled (non continuous slope) }; DECLARE_ENUM_AS_BIT_SET(Slope) /** * Helper for creating a bitset of slopes. * @param x The slope to convert into a bitset. */ #define M(x) (1U << (x)) /** Constant bitset with safe slopes for building a level crossing. */ static const uint32_t VALID_LEVEL_CROSSING_SLOPES = M(SLOPE_SEN) | M(SLOPE_ENW) | M(SLOPE_NWS) | M(SLOPE_NS) | M(SLOPE_WSE) | M(SLOPE_EW) | M(SLOPE_FLAT); #undef M /** * Enumeration for Foundations. */ enum Foundation { FOUNDATION_NONE, ///< The tile has no foundation, the slope remains unchanged. FOUNDATION_LEVELED, ///< The tile is leveled up to a flat slope. FOUNDATION_INCLINED_X, ///< The tile has an along X-axis inclined foundation. FOUNDATION_INCLINED_Y, ///< The tile has an along Y-axis inclined foundation. FOUNDATION_STEEP_LOWER, ///< The tile has a steep slope. The lowest corner is raised by a foundation to allow building railroad on the lower halftile. /* Halftile foundations */ FOUNDATION_STEEP_BOTH, ///< The tile has a steep slope. The lowest corner is raised by a foundation and the upper halftile is leveled. FOUNDATION_HALFTILE_W, ///< Level west halftile non-continuously. FOUNDATION_HALFTILE_S, ///< Level south halftile non-continuously. FOUNDATION_HALFTILE_E, ///< Level east halftile non-continuously. FOUNDATION_HALFTILE_N, ///< Level north halftile non-continuously. /* Special anti-zig-zag foundations for single horizontal/vertical track */ FOUNDATION_RAIL_W, ///< Foundation for TRACK_BIT_LEFT, but not a leveled foundation. FOUNDATION_RAIL_S, ///< Foundation for TRACK_BIT_LOWER, but not a leveled foundation. FOUNDATION_RAIL_E, ///< Foundation for TRACK_BIT_RIGHT, but not a leveled foundation. FOUNDATION_RAIL_N, ///< Foundation for TRACK_BIT_UPPER, but not a leveled foundation. FOUNDATION_INVALID = 0xFF, ///< Used inside "rail_cmd.cpp" to indicate invalid slope/track combination. }; #endif /* SLOPE_TYPE_H */