1 // ATCutils.hxx - Utility functions for the ATC / AI subsytem
3 // Written by David Luff, started March 2002.
5 // Copyright (C) 2002 David C Luff - david.luff@nottingham.ac.uk
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21 #include <Airports/airport.hxx>
22 #include <Airports/runways.hxx>
28 // These are defined here because I had a problem with SG_DEGREES_TO_RADIANS
29 #define DCL_PI 3.1415926535f
30 #define DCL_DEGREES_TO_RADIANS (DCL_PI/180.0)
31 #define DCL_RADIANS_TO_DEGREES (180.0/DCL_PI)
33 /*******************************
35 * Communication functions
37 ********************************/
39 // Convert any number to spoken digits
40 string ConvertNumToSpokenDigits(const string &n);
42 // Convert an integer to spoken digits
43 string ConvertNumToSpokenDigits(const int& n);
44 string decimalNumeral(const int& n);
46 // Convert rwy number string to a spoken-style string
47 // eg "15L" to "one five left"
48 // Assumes we get a string of digits optionally appended with R, L, or C
50 string ConvertRwyNumToSpokenString(const string &s);
53 // Return the phonetic letter of a letter represented as an integer 0..25
54 string GetPhoneticLetter(const int i);
56 // Return the phonetic letter of a character in the range a-z or A-Z.
57 // Currently always returns prefixed by lowercase.
58 string GetPhoneticLetter(char c);
60 // Get the compass direction associated with a heading in degrees
61 // Currently returns 8 direction resolution (N, NE, E etc...)
62 // Might be modified in future to return 4, 8 or 16 resolution but defaulting to 8.
63 string GetCompassDirection(double h);
65 /*******************************
67 * Positional functions
69 ********************************/
71 // Given two positions (lat & lon in degrees), get the HORIZONTAL separation (in meters)
72 double dclGetHorizontalSeparation(const SGGeod& pos1, const SGGeod& pos2);
74 // Given a point and a line, get the HORIZONTAL shortest distance from the point to a point on the line.
75 // Expects to be fed orthogonal co-ordinates, NOT lat & lon !
76 double dclGetLinePointSeparation(double px, double py, double x1, double y1, double x2, double y2);
78 // Given a position (lat/lon/elev), heading, vertical angle, and distance, calculate the new position.
79 // Assumes that the ground is not hit!!! Expects heading and angle in degrees, distance in meters.
80 SGGeod dclUpdatePosition(const SGGeod& pos, double heading, double angle, double distance);
82 // Get a heading from one lat/lon to another (in degrees)
83 double GetHeadingFromTo(const SGGeod& A, const SGGeod& B);
85 // Given a heading (in degrees), bound it from 0 -> 360
86 void dclBoundHeading(double &hdg);
88 // smallest difference between two angles in degrees
89 // difference is negative if a1 > a2 and positive if a2 > a1
90 double GetAngleDiff_deg( const double &a1, const double &a2);
98 // Given (lon/lat/elev) and an FGRunway struct, determine if the point lies on the runway
99 bool OnRunway(const SGGeod& pt, const FGRunwayBase* rwy);