1 // viewer.cxx -- class for managing a viewer in the flightgear world.
3 // Written by Curtis Olson, started August 1997.
4 // overhaul started October 2000.
6 // Copyright (C) 1997 - 2000 Curtis L. Olson - curt@flightgear.org
8 // This program is free software; you can redistribute it and/or
9 // modify it under the terms of the GNU General Public License as
10 // published by the Free Software Foundation; either version 2 of the
11 // License, or (at your option) any later version.
13 // This program is distributed in the hope that it will be useful, but
14 // WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 // General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 #include <simgear/compiler.h>
31 #include <simgear/debug/logstream.hxx>
32 #include <simgear/constants.h>
38 FGViewer::FGViewer( void ):
43 sgSetVec3( pilot_offset, 0.0, 0.0, 0.0 );
44 sgdZeroVec3(geod_view_pos);
45 sgdZeroVec3(abs_view_pos);
46 sea_level_radius = SG_EQUATORIAL_RADIUS_M;
47 //a reasonable guess for init, so that the math doesn't blow up
51 // Update the view parameters
52 void FGViewer::update() {
53 SG_LOG( SG_VIEW, SG_ALERT, "Shouldn't ever see this" );
58 FGViewer::~FGViewer( void ) {
77 FGViewer::update (int dt)
79 for ( int i = 0; i < dt; i++ ) {
80 if ( fabs(get_goal_view_offset() - get_view_offset()) < 0.05 ) {
81 set_view_offset( get_goal_view_offset() );
84 // move current_view.view_offset towards
85 // current_view.goal_view_offset
86 if ( get_goal_view_offset() > get_view_offset() )
88 if ( get_goal_view_offset() - get_view_offset() < SGD_PI ){
89 inc_view_offset( 0.01 );
91 inc_view_offset( -0.01 );
94 if ( get_view_offset() - get_goal_view_offset() < SGD_PI ){
95 inc_view_offset( -0.01 );
97 inc_view_offset( 0.01 );
100 if ( get_view_offset() > SGD_2PI ) {
101 inc_view_offset( -SGD_2PI );
102 } else if ( get_view_offset() < 0 ) {
103 inc_view_offset( SGD_2PI );