1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
|
/* $Id$ */
/*
* 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 ground_vehicle.hpp Base class and functions for all vehicles that move through ground. */
#ifndef GROUND_VEHICLE_HPP
#define GROUND_VEHICLE_HPP
#include "vehicle_base.h"
#include "landscape.h"
/** What is the status of our acceleration? */
enum AccelStatus {
AS_ACCEL, ///< We want to go faster, if possible of course.
AS_BRAKE ///< We want to stop.
};
/**
* Cached, frequently calculated values.
* All of these values except cached_slope_resistance are set only for the first part of a vehicle.
*/
struct GroundVehicleCache {
/* Cached acceleration values, recalculated when the cargo on a vehicle changes (in addition to the conditions below) */
uint32 cached_weight; ///< Total weight of the consist (valid only for the first engine).
uint32 cached_slope_resistance; ///< Resistance caused by weight when this vehicle part is at a slope.
uint32 cached_max_te; ///< Maximum tractive effort of consist (valid only for the first engine).
uint16 cached_axle_resistance; ///< Resistance caused by the axles of the vehicle (valid only for the first engine).
/* Cached acceleration values, recalculated on load and each time a vehicle is added to/removed from the consist. */
uint16 cached_max_track_speed; ///< Maximum consist speed limited by track type (valid only for the first engine).
uint32 cached_power; ///< Total power of the consist (valid only for the first engine).
uint32 cached_air_drag; ///< Air drag coefficient of the vehicle (valid only for the first engine).
/* Cached NewGRF values, recalculated on load and each time a vehicle is added to/removed from the consist. */
uint16 cached_total_length; ///< Length of the whole vehicle (valid only for the first engine).
EngineID first_engine; ///< Cached EngineID of the front vehicle. INVALID_ENGINE for the front vehicle itself.
uint8 cached_veh_length; ///< Length of this vehicle in units of 1/8 of normal length. It is cached because this can be set by a callback.
};
/** Ground vehicle flags. */
enum GroundVehicleFlags {
GVF_GOINGUP_BIT = 0,
GVF_GOINGDOWN_BIT = 1,
};
/**
* Base class for all vehicles that move through ground.
*
* Child classes must define all of the following functions.
* These functions are not defined as pure virtual functions at this class to improve performance.
*
* virtual uint16 GetPower() const = 0;
* virtual uint16 GetPoweredPartPower(const T *head) const = 0;
* virtual uint16 GetWeight() const = 0;
* virtual byte GetTractiveEffort() const = 0;
* virtual byte GetAirDrag() const = 0;
* virtual byte GetAirDragArea() const = 0;
* virtual AccelStatus GetAccelerationStatus() const = 0;
* virtual uint16 GetCurrentSpeed() const = 0;
* virtual uint32 GetRollingFriction() const = 0;
* virtual int GetAccelerationType() const = 0;
* virtual int32 GetSlopeSteepness() const = 0;
* virtual int GetDisplayMaxSpeed() const = 0;
* virtual uint16 GetMaxTrackSpeed() const = 0;
* virtual bool TileMayHaveSlopedTrack() const = 0;
*/
template <class T, VehicleType Type>
struct GroundVehicle : public SpecializedVehicle<T, Type> {
GroundVehicleCache gcache; ///< Cache of often calculated values.
uint16 gv_flags; ///< @see GroundVehicleFlags.
/**
* The constructor at SpecializedVehicle must be called.
*/
GroundVehicle() : SpecializedVehicle<T, Type>() {}
void PowerChanged();
void CargoChanged();
int GetAcceleration() const;
/**
* Calculates the total slope resistance for this vehicle.
* @return Slope resistance.
*/
FORCEINLINE int32 GetSlopeResistance() const
{
int32 incl = 0;
for (const T *u = T::From(this); u != NULL; u = u->Next()) {
if (HasBit(u->gv_flags, GVF_GOINGUP_BIT)) {
incl += u->gcache.cached_slope_resistance;
} else if (HasBit(u->gv_flags, GVF_GOINGDOWN_BIT)) {
incl -= u->gcache.cached_slope_resistance;
}
}
return incl;
}
/**
* Checks if the vehicle is in a slope and sets the required flags in that case.
* @param new_tile True if the vehicle reached a new tile.
* @param turned Indicates if the vehicle has turned.
* @return Old height of the vehicle.
*/
FORCEINLINE byte UpdateInclination(bool new_tile, bool turned)
{
byte old_z = this->z_pos;
this->z_pos = GetSlopeZ(this->x_pos, this->y_pos);
if (new_tile) {
ClrBit(this->gv_flags, GVF_GOINGUP_BIT);
ClrBit(this->gv_flags, GVF_GOINGDOWN_BIT);
if (T::From(this)->TileMayHaveSlopedTrack()) {
/* To check whether the current tile is sloped, and in which
* direction it is sloped, we get the 'z' at the center of
* the tile (middle_z) and the edge of the tile (old_z),
* which we then can compare. */
static const int HALF_TILE_SIZE = TILE_SIZE / 2;
static const int INV_TILE_SIZE_MASK = ~(TILE_SIZE - 1);
byte middle_z = GetSlopeZ((this->x_pos & INV_TILE_SIZE_MASK) | HALF_TILE_SIZE, (this->y_pos & INV_TILE_SIZE_MASK) | HALF_TILE_SIZE);
if (middle_z != this->z_pos) {
SetBit(this->gv_flags, (middle_z > old_z) ? GVF_GOINGUP_BIT : GVF_GOINGDOWN_BIT);
}
}
}
this->UpdateViewport(true, turned);
return old_z;
}
};
#endif /* GROUND_VEHICLE_HPP */
|
