1 // ATCProjection.hxx - A convienience projection class for the ATC/AI system.
3 // Written by David Luff, started 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., 675 Mass Ave, Cambridge, MA 02139, USA.
21 #ifndef _FG_ATC_PROJECTION_HXX
22 #define _FG_ATC_PROJECTION_HXX
24 #include <simgear/math/point3d.hxx>
26 // FGATCProjection - a class to project an area local to an airport onto an orthogonal co-ordinate system
27 class FGATCProjection {
31 FGATCProjection(const Point3D& centre);
34 void Init(const Point3D& centre);
36 // Convert a lat/lon co-ordinate (degrees) to the local projection (meters)
37 Point3D ConvertToLocal(const Point3D& pt);
39 // Convert a local projection co-ordinate (meters) to lat/lon (degrees)
40 Point3D ConvertFromLocal(const Point3D& pt);
43 Point3D origin; // lat/lon of local area origin
44 double correction_factor; // Reduction in surface distance per degree of longitude due to latitude. Saves having to do a cos() every call.
49 // FGATCAlignedProjection - a class to project an area local to a runway onto an orthogonal co-ordinate system
50 // with the origin at the threshold and the runway aligned with the y axis.
51 class FGATCAlignedProjection {
54 FGATCAlignedProjection();
55 ~FGATCAlignedProjection();
57 void Init(const Point3D& centre, double heading);
59 // Convert a lat/lon co-ordinate (degrees) to the local projection (meters)
60 Point3D ConvertToLocal(const Point3D& pt);
62 // Convert a local projection co-ordinate (meters) to lat/lon (degrees)
63 Point3D ConvertFromLocal(const Point3D& pt);
66 Point3D origin; // lat/lon of local area origin (the threshold)
67 double theta; // the rotation angle for alignment in radians
68 double correction_factor; // Reduction in surface distance per degree of longitude due to latitude. Saves having to do a cos() every call.
72 #endif // _FG_ATC_PROJECTION_HXX