1
/*****************************************************************************
3
Header: FGAirPressureItem.h
4
Author: Christian Mayer
7
-------- Copyright (C) 1999 Christian Mayer (fgfs@christianmayer.de) --------
9
This program is free software; you can redistribute it and/or modify it under
10
the terms of the GNU General Public License as published by the Free Software
11
Foundation; either version 2 of the License, or (at your option) any later
14
This program is distributed in the hope that it will be useful, but WITHOUT
15
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
16
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
19
You should have received a copy of the GNU General Public License along with
20
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
21
Place - Suite 330, Boston, MA 02111-1307, USA.
23
Further information about the GNU General Public License can also be found on
24
the world wide web at http://www.gnu.org.
26
FUNCTIONAL DESCRIPTION
27
------------------------------------------------------------------------------
28
Air pressure item that is stored in the micro weather class
31
------------------------------------------------------------------------------
32
28.05.1999 Christian Mayer Created
33
08.06.1999 Christian Mayer Added international air preasure formula
34
16.06.1999 Durk Talsma Portability for Linux
35
20.06.1999 Christian Mayer added lots of consts
36
11.10.1999 Christian Mayer changed set<> to map<> on Bernie Bright's
38
19.10.1999 Christian Mayer change to use PLIB's sg instead of Point[2/3]D
39
and lots of wee code cleaning
40
15.12.1999 Christian Mayer changed the air pressure calculation to a much
41
more realistic formula. But as I need for that
42
the temperature I moved the code to
44
*****************************************************************************/
46
/****************************************************************************/
48
/****************************************************************************/
49
#ifndef FGAirPressureItem_H
50
#define FGAirPressureItem_H
52
/****************************************************************************/
54
/****************************************************************************/
57
#include "FGWeatherDefs.h"
59
/****************************************************************************/
61
/****************************************************************************/
62
class FGAirPressureItem;
63
FGAirPressureItem operator-(const FGAirPressureItem& arg);
65
/****************************************************************************/
66
/* CLASS DECLARATION */
67
/* NOTE: The value stored in 'value' is the air preasure that we'd have at */
68
/* an altitude of 0.0 The correct airpreasure at the stored altitude */
69
/* gets calulated in FGPhyiscalProperties as I need to know the */
70
/* temperatures at the different altitudes for that. */
71
/****************************************************************************/
72
class FGAirPressureItem
75
WeatherPrecision value; //that's the airpressure at 0 metres
80
FGAirPressureItem(const WeatherPrecision v) {value = v; }
81
FGAirPressureItem() {value = FG_WEATHER_DEFAULT_AIRPRESSURE;}
83
WeatherPrecision getValue(void) const
88
FGAirPressureItem& operator*=(const WeatherPrecision arg);
89
FGAirPressureItem& operator+=(const FGAirPressureItem& arg);
90
FGAirPressureItem& operator-=(const FGAirPressureItem& arg);
92
friend FGAirPressureItem operator-(const FGAirPressureItem& arg);
95
inline FGAirPressureItem& FGAirPressureItem::operator*= (const WeatherPrecision arg)
101
inline FGAirPressureItem& FGAirPressureItem::operator+= (const FGAirPressureItem& arg)
107
inline FGAirPressureItem& FGAirPressureItem::operator-= (const FGAirPressureItem& arg)
113
inline FGAirPressureItem operator-(const FGAirPressureItem& arg)
115
return FGAirPressureItem(-arg.value);
118
/****************************************************************************/
119
#endif /*FGAirPressureItem_H*/