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flightgear/src/Main/viewmgr.cxx

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// viewmgr.cxx -- class for managing all the views in the flightgear world.
//
// Written by Curtis Olson, started October 2000.
// partially rewritten by Jim Wilson March 2002
//
// Copyright (C) 2000 Curtis L. Olson - http://www.flightgear.org/~curt
//
// This program 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; either version 2 of the
// License, or (at your option) any later version.
//
// This program 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 this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
//
// $Id$
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "viewmgr.hxx"
#include <string.h> // strcmp
#include <simgear/compiler.h>
#include <simgear/sound/soundmgr_openal.hxx>
#include <Model/acmodel.hxx>
#include <Main/viewer.hxx>
#include <Main/fg_props.hxx>
// Constructor
FGViewMgr::FGViewMgr( void ) :
axis_long(0),
axis_lat(0),
view_number(fgGetNode("/sim/current-view/view-number", true)),
config_list(fgGetNode("/sim", true)->getChildren("view")),
current(0)
{
}
// Destructor
FGViewMgr::~FGViewMgr( void ) {
}
void
FGViewMgr::init ()
{
double aspect_ratio_multiplier
= fgGetDouble("/sim/current-view/aspect-ratio-multiplier");
for (unsigned int i = 0; i < config_list.size(); i++) {
SGPropertyNode *n = config_list[i];
// find out if this is an internal view (e.g. in cockpit, low near plane)
bool internal = n->getBoolValue("internal", false);
// FIXME:
// this is assumed to be an aircraft model...we will need to read
// model-from-type as well.
// find out if this is a model we are looking from...
bool from_model = n->getBoolValue("config/from-model");
int from_model_index = n->getIntValue("config/from-model-idx");
double x_offset_m = n->getDoubleValue("config/x-offset-m");
double y_offset_m = n->getDoubleValue("config/y-offset-m");
double z_offset_m = n->getDoubleValue("config/z-offset-m");
double heading_offset_deg = n->getDoubleValue("config/heading-offset-deg");
n->setDoubleValue("config/heading-offset-deg", heading_offset_deg);
double pitch_offset_deg = n->getDoubleValue("config/pitch-offset-deg");
n->setDoubleValue("config/pitch-offset-deg", pitch_offset_deg);
double roll_offset_deg = n->getDoubleValue("config/roll-offset-deg");
n->setDoubleValue("config/roll-offset-deg", roll_offset_deg);
double fov_deg = n->getDoubleValue("config/default-field-of-view-deg");
double near_m = n->getDoubleValue("config/ground-level-nearplane-m");
// supporting two types "lookat" = 1 and "lookfrom" = 0
const char *type = n->getStringValue("type");
if (!strcmp(type, "lookat")) {
bool at_model = n->getBoolValue("config/at-model");
int at_model_index = n->getIntValue("config/at-model-idx");
double damp_roll = n->getDoubleValue("config/at-model-roll-damping");
double damp_pitch = n->getDoubleValue("config/at-model-pitch-damping");
double damp_heading = n->getDoubleValue("config/at-model-heading-damping");
double target_x_offset_m = n->getDoubleValue("config/target-x-offset-m");
double target_y_offset_m = n->getDoubleValue("config/target-y-offset-m");
double target_z_offset_m = n->getDoubleValue("config/target-z-offset-m");
add_view(new FGViewer ( FG_LOOKAT, from_model, from_model_index,
at_model, at_model_index,
damp_roll, damp_pitch, damp_heading,
x_offset_m, y_offset_m,z_offset_m,
heading_offset_deg, pitch_offset_deg,
roll_offset_deg, fov_deg, aspect_ratio_multiplier,
target_x_offset_m, target_y_offset_m,
target_z_offset_m, near_m, internal ));
} else {
add_view(new FGViewer ( FG_LOOKFROM, from_model, from_model_index,
false, 0, 0.0, 0.0, 0.0,
x_offset_m, y_offset_m, z_offset_m,
heading_offset_deg, pitch_offset_deg,
roll_offset_deg, fov_deg, aspect_ratio_multiplier,
0, 0, 0, near_m, internal ));
}
}
copyToCurrent();
}
void
FGViewMgr::reinit ()
{
// reset offsets and fov to configuration defaults
for (unsigned int i = 0; i < config_list.size(); i++) {
SGPropertyNode *n = config_list[i];
setView(i);
fgSetDouble("/sim/current-view/x-offset-m",
n->getDoubleValue("config/x-offset-m"));
fgSetDouble("/sim/current-view/y-offset-m",
n->getDoubleValue("config/y-offset-m"));
fgSetDouble("/sim/current-view/z-offset-m",
n->getDoubleValue("config/z-offset-m"));
fgSetDouble("/sim/current-view/pitch-offset-deg",
n->getDoubleValue("config/pitch-offset-deg"));
fgSetDouble("/sim/current-view/heading-offset-deg",
n->getDoubleValue("config/heading-offset-deg"));
fgSetDouble("/sim/current-view/roll-offset-deg",
n->getDoubleValue("config/roll-offset-deg"));
double fov_deg = n->getDoubleValue("config/default-field-of-view-deg");
if (fov_deg < 10.0)
fov_deg = 55.0;
fgSetDouble("/sim/current-view/field-of-view", fov_deg);
// target offsets for lookat mode only...
fgSetDouble("/sim/current-view/target-x-offset-m",
n->getDoubleValue("config/target-x-offset-m"));
fgSetDouble("/sim/current-view/target-y-offset-m",
n->getDoubleValue("config/target-y-offset-m"));
fgSetDouble("/sim/current-view/target-z-offset-m",
n->getDoubleValue("config/target-z-offset-m"));
}
setView(0);
}
typedef double (FGViewMgr::*double_getter)() const;
void
FGViewMgr::bind ()
{
// these are bound to the current view properties
fgTie("/sim/current-view/heading-offset-deg", this,
&FGViewMgr::getViewHeadingOffset_deg,
&FGViewMgr::setViewHeadingOffset_deg);
fgSetArchivable("/sim/current-view/heading-offset-deg");
fgTie("/sim/current-view/goal-heading-offset-deg", this,
&FGViewMgr::getViewGoalHeadingOffset_deg,
&FGViewMgr::setViewGoalHeadingOffset_deg);
fgSetArchivable("/sim/current-view/goal-heading-offset-deg");
fgTie("/sim/current-view/pitch-offset-deg", this,
&FGViewMgr::getViewPitchOffset_deg,
&FGViewMgr::setViewPitchOffset_deg);
fgSetArchivable("/sim/current-view/pitch-offset-deg");
fgTie("/sim/current-view/goal-pitch-offset-deg", this,
&FGViewMgr::getGoalViewPitchOffset_deg,
&FGViewMgr::setGoalViewPitchOffset_deg);
fgSetArchivable("/sim/current-view/goal-pitch-offset-deg");
fgTie("/sim/current-view/roll-offset-deg", this,
&FGViewMgr::getViewRollOffset_deg,
&FGViewMgr::setViewRollOffset_deg);
fgSetArchivable("/sim/current-view/roll-offset-deg");
fgTie("/sim/current-view/goal-roll-offset-deg", this,
&FGViewMgr::getGoalViewRollOffset_deg,
&FGViewMgr::setGoalViewRollOffset_deg);
fgSetArchivable("/sim/current-view/goal-roll-offset-deg");
fgTie("/sim/current-view/view-number", this,
&FGViewMgr::getView, &FGViewMgr::setView);
fgSetArchivable("/sim/current-view/view-number", FALSE);
fgTie("/sim/current-view/axes/long", this,
(double_getter)0, &FGViewMgr::setViewAxisLong);
fgSetArchivable("/sim/current-view/axes/long");
fgTie("/sim/current-view/axes/lat", this,
(double_getter)0, &FGViewMgr::setViewAxisLat);
fgSetArchivable("/sim/current-view/axes/lat");
fgTie("/sim/current-view/field-of-view", this,
&FGViewMgr::getFOV_deg, &FGViewMgr::setFOV_deg);
fgSetArchivable("/sim/current-view/field-of-view");
fgTie("/sim/current-view/aspect-ratio-multiplier", this,
&FGViewMgr::getARM_deg, &FGViewMgr::setARM_deg);
fgSetArchivable("/sim/current-view/field-of-view");
fgTie("/sim/current-view/ground-level-nearplane-m", this,
&FGViewMgr::getNear_m, &FGViewMgr::setNear_m);
fgSetArchivable("/sim/current-view/ground-level-nearplane-m");
SGPropertyNode *n = fgGetNode("/sim/current-view", true);
n->tie("viewer-x-m", SGRawValuePointer<double>(&abs_viewer_position[0]));
n->tie("viewer-y-m", SGRawValuePointer<double>(&abs_viewer_position[1]));
n->tie("viewer-z-m", SGRawValuePointer<double>(&abs_viewer_position[2]));
}
void
FGViewMgr::unbind ()
{
// FIXME:
// need to redo these bindings to the new locations (move to viewer?)
fgUntie("/sim/current-view/heading-offset-deg");
fgUntie("/sim/current-view/goal-heading-offset-deg");
fgUntie("/sim/current-view/pitch-offset-deg");
fgUntie("/sim/current-view/goal-pitch-offset-deg");
fgUntie("/sim/current-view/field-of-view");
fgUntie("/sim/current-view/aspect-ratio-multiplier");
fgUntie("/sim/current-view/view-number");
fgUntie("/sim/current-view/axes/long");
fgUntie("/sim/current-view/axes/lat");
fgUntie("/sim/current-view/ground-level-nearplane-m");
fgUntie("/sim/current-view/viewer-x-m");
fgUntie("/sim/current-view/viewer-y-m");
fgUntie("/sim/current-view/viewer-z-m");
}
void
FGViewMgr::update (double dt)
{
FGViewer * view = get_current_view();
if (view == 0)
return;
FGViewer *loop_view = (FGViewer *)get_view(current);
SGPropertyNode *n = config_list[current];
double lon_deg, lat_deg, alt_ft, roll_deg, pitch_deg, heading_deg;
// Set up view location and orientation
if (!n->getBoolValue("config/from-model")) {
lon_deg = fgGetDouble(n->getStringValue("config/eye-lon-deg-path"));
lat_deg = fgGetDouble(n->getStringValue("config/eye-lat-deg-path"));
alt_ft = fgGetDouble(n->getStringValue("config/eye-alt-ft-path"));
roll_deg = fgGetDouble(n->getStringValue("config/eye-roll-deg-path"));
pitch_deg = fgGetDouble(n->getStringValue("config/eye-pitch-deg-path"));
heading_deg = fgGetDouble(n->getStringValue("config/eye-heading-deg-path"));
loop_view->setPosition(lon_deg, lat_deg, alt_ft);
loop_view->setOrientation(roll_deg, pitch_deg, heading_deg);
} else {
// force recalc in viewer
loop_view->set_dirty();
}
// if lookat (type 1) then get target data...
if (loop_view->getType() == FG_LOOKAT) {
if (!n->getBoolValue("config/from-model")) {
lon_deg = fgGetDouble(n->getStringValue("config/target-lon-deg-path"));
lat_deg = fgGetDouble(n->getStringValue("config/target-lat-deg-path"));
alt_ft = fgGetDouble(n->getStringValue("config/target-alt-ft-path"));
roll_deg = fgGetDouble(n->getStringValue("config/target-roll-deg-path"));
pitch_deg = fgGetDouble(n->getStringValue("config/target-pitch-deg-path"));
heading_deg = fgGetDouble(n->getStringValue("config/target-heading-deg-path"));
loop_view->setTargetPosition(lon_deg, lat_deg, alt_ft);
loop_view->setTargetOrientation(roll_deg, pitch_deg, heading_deg);
} else {
loop_view->set_dirty();
}
}
setViewXOffset_m(fgGetDouble("/sim/current-view/x-offset-m"));
setViewYOffset_m(fgGetDouble("/sim/current-view/y-offset-m"));
setViewZOffset_m(fgGetDouble("/sim/current-view/z-offset-m"));
setViewTargetXOffset_m(fgGetDouble("/sim/current-view/target-x-offset-m"));
setViewTargetYOffset_m(fgGetDouble("/sim/current-view/target-y-offset-m"));
setViewTargetZOffset_m(fgGetDouble("/sim/current-view/target-z-offset-m"));
// Update the current view
do_axes();
view->update(dt);
abs_viewer_position = loop_view->getViewPosition();
// update audio listener values
static SGSoundMgr *smgr = 0;
if (!smgr) smgr = (SGSoundMgr *)globals->get_subsystem("soundmgr");
if (smgr) {
// set the viewer posotion in Cartesian coordinates in meters
smgr->set_position(abs_viewer_position);
smgr->set_orientation(loop_view->getViewOrientation());
//TODO: should be in meters per second
// smr->set_veloicty(SGVec3f(0,0,0));
}
}
void
FGViewMgr::copyToCurrent()
{
SGPropertyNode *n = config_list[current];
fgSetString("/sim/current-view/name", n->getStringValue("name"));
fgSetString("/sim/current-view/type", n->getStringValue("type"));
// copy certain view config data for default values
fgSetDouble("/sim/current-view/config/heading-offset-deg",
n->getDoubleValue("config/default-heading-offset-deg"));
fgSetDouble("/sim/current-view/config/pitch-offset-deg",
n->getDoubleValue("config/pitch-offset-deg"));
fgSetDouble("/sim/current-view/config/roll-offset-deg",
n->getDoubleValue("config/roll-offset-deg"));
fgSetDouble("/sim/current-view/config/default-field-of-view-deg",
n->getDoubleValue("config/default-field-of-view-deg"));
fgSetBool("/sim/current-view/config/from-model",
n->getBoolValue("config/from-model"));
// copy view data
fgSetDouble("/sim/current-view/x-offset-m", getViewXOffset_m());
fgSetDouble("/sim/current-view/y-offset-m", getViewYOffset_m());
fgSetDouble("/sim/current-view/z-offset-m", getViewZOffset_m());
fgSetDouble("/sim/current-view/goal-heading-offset-deg",
get_current_view()->getGoalHeadingOffset_deg());
fgSetDouble("/sim/current-view/goal-pitch-offset-deg",
get_current_view()->getGoalPitchOffset_deg());
fgSetDouble("/sim/current-view/goal-roll-offset-deg",
get_current_view()->getRollOffset_deg());
fgSetDouble("/sim/current-view/heading-offset-deg",
get_current_view()->getHeadingOffset_deg());
fgSetDouble("/sim/current-view/pitch-offset-deg",
get_current_view()->getPitchOffset_deg());
fgSetDouble("/sim/current-view/roll-offset-deg",
get_current_view()->getRollOffset_deg());
fgSetDouble("/sim/current-view/target-x-offset-m",
get_current_view()->getTargetXOffset_m());
fgSetDouble("/sim/current-view/target-y-offset-m",
get_current_view()->getTargetYOffset_m());
fgSetDouble("/sim/current-view/target-z-offset-m",
get_current_view()->getTargetZOffset_m());
fgSetBool("/sim/current-view/internal",
get_current_view()->getInternal());
}
void FGViewMgr::clear()
{
views.clear();
}
FGViewer*
FGViewMgr::get_current_view()
{
if ( current < (int)views.size() ) {
return views[current];
} else {
return NULL;
}
}
const FGViewer*
FGViewMgr::get_current_view() const
{
if ( current < (int)views.size() ) {
return views[current];
} else {
return NULL;
}
}
FGViewer*
FGViewMgr::get_view( int i )
{
if ( i < 0 ) { i = 0; }
if ( i >= (int)views.size() ) { i = views.size() - 1; }
return views[i];
}
const FGViewer*
FGViewMgr::get_view( int i ) const
{
if ( i < 0 ) { i = 0; }
if ( i >= (int)views.size() ) { i = views.size() - 1; }
return views[i];
}
FGViewer*
FGViewMgr::next_view()
{
setView((current+1 < (int)views.size()) ? (current + 1) : 0);
view_number->fireValueChanged();
return views[current];
}
FGViewer*
FGViewMgr::prev_view()
{
setView((0 < current) ? (current - 1) : (views.size() - 1));
view_number->fireValueChanged();
return views[current];
}
void
FGViewMgr::add_view( FGViewer * v )
{
views.push_back(v);
v->init();
}
double
FGViewMgr::getViewHeadingOffset_deg () const
{
const FGViewer * view = get_current_view();
return (view == 0 ? 0 : view->getHeadingOffset_deg());
}
void
FGViewMgr::setViewHeadingOffset_deg (double offset)
{
FGViewer * view = get_current_view();
if (view != 0) {
view->setGoalHeadingOffset_deg(offset);
view->setHeadingOffset_deg(offset);
}
}
double
FGViewMgr::getViewGoalHeadingOffset_deg () const
{
const FGViewer * view = get_current_view();
return (view == 0 ? 0 : view->getGoalHeadingOffset_deg());
}
void
FGViewMgr::setViewGoalHeadingOffset_deg (double offset)
{
FGViewer * view = get_current_view();
if (view != 0)
view->setGoalHeadingOffset_deg(offset);
}
double
FGViewMgr::getViewPitchOffset_deg () const
{
const FGViewer * view = get_current_view();
return (view == 0 ? 0 : view->getPitchOffset_deg());
}
void
FGViewMgr::setViewPitchOffset_deg (double tilt)
{
FGViewer * view = get_current_view();
if (view != 0) {
view->setGoalPitchOffset_deg(tilt);
view->setPitchOffset_deg(tilt);
}
}
double
FGViewMgr::getGoalViewPitchOffset_deg () const
{
const FGViewer * view = get_current_view();
return (view == 0 ? 0 : view->getGoalPitchOffset_deg());
}
void
FGViewMgr::setGoalViewPitchOffset_deg (double tilt)
{
FGViewer * view = get_current_view();
if (view != 0)
view->setGoalPitchOffset_deg(tilt);
}
double
FGViewMgr::getViewRollOffset_deg () const
{
const FGViewer * view = get_current_view();
return (view == 0 ? 0 : view->getRollOffset_deg());
}
void
FGViewMgr::setViewRollOffset_deg (double tilt)
{
FGViewer * view = get_current_view();
if (view != 0) {
view->setGoalRollOffset_deg(tilt);
view->setRollOffset_deg(tilt);
}
}
double
FGViewMgr::getGoalViewRollOffset_deg () const
{
const FGViewer * view = get_current_view();
return (view == 0 ? 0 : view->getGoalRollOffset_deg());
}
void
FGViewMgr::setGoalViewRollOffset_deg (double tilt)
{
FGViewer * view = get_current_view();
if (view != 0)
view->setGoalRollOffset_deg(tilt);
}
double
FGViewMgr::getViewXOffset_m () const
{
const FGViewer * view = get_current_view();
if (view != 0) {
return ((FGViewer *)view)->getXOffset_m();
} else {
return 0;
}
}
void
FGViewMgr::setViewXOffset_m (double x)
{
FGViewer * view = get_current_view();
if (view != 0) {
view->setXOffset_m(x);
}
}
double
FGViewMgr::getViewYOffset_m () const
{
const FGViewer * view = get_current_view();
if (view != 0) {
return ((FGViewer *)view)->getYOffset_m();
} else {
return 0;
}
}
void
FGViewMgr::setViewYOffset_m (double y)
{
FGViewer * view = get_current_view();
if (view != 0) {
view->setYOffset_m(y);
}
}
double
FGViewMgr::getViewZOffset_m () const
{
const FGViewer * view = get_current_view();
if (view != 0) {
return ((FGViewer *)view)->getZOffset_m();
} else {
return 0;
}
}
void
FGViewMgr::setViewZOffset_m (double z)
{
FGViewer * view = get_current_view();
if (view != 0) {
view->setZOffset_m(z);
}
}
double
FGViewMgr::getViewTargetXOffset_m () const
{
const FGViewer * view = get_current_view();
if (view != 0) {
return ((FGViewer *)view)->getTargetXOffset_m();
} else {
return 0;
}
}
void
FGViewMgr::setViewTargetXOffset_m (double x)
{
FGViewer * view = get_current_view();
if (view != 0) {
view->setTargetXOffset_m(x);
}
}
double
FGViewMgr::getViewTargetYOffset_m () const
{
const FGViewer * view = get_current_view();
if (view != 0) {
return ((FGViewer *)view)->getTargetYOffset_m();
} else {
return 0;
}
}
void
FGViewMgr::setViewTargetYOffset_m (double y)
{
FGViewer * view = get_current_view();
if (view != 0) {
view->setTargetYOffset_m(y);
}
}
double
FGViewMgr::getViewTargetZOffset_m () const
{
const FGViewer * view = get_current_view();
if (view != 0) {
return ((FGViewer *)view)->getTargetZOffset_m();
} else {
return 0;
}
}
void
FGViewMgr::setViewTargetZOffset_m (double z)
{
FGViewer * view = get_current_view();
if (view != 0) {
view->setTargetZOffset_m(z);
}
}
int
FGViewMgr::getView () const
{
return ( current );
}
void
FGViewMgr::setView (int newview)
{
// negative numbers -> set view with node index -newview
if (newview < 0) {
for (int i = 0; i < (int)config_list.size(); i++) {
int index = -config_list[i]->getIndex();
if (index == newview)
newview = i;
}
if (newview < 0)
return;
}
// if newview number too low wrap to last view...
if (newview < 0)
newview = (int)views.size() - 1;
// if newview number to high wrap to zero...
if (newview >= (int)views.size())
newview = 0;
// set new view
set_view(newview);
// copy in view data
copyToCurrent();
// Copy the fdm's position into the SGLocation which is shared with
// some views ...
globals->get_aircraft_model()->update(0);
// Do the update ...
update(0);
}
double
FGViewMgr::getFOV_deg () const
{
const FGViewer * view = get_current_view();
return (view == 0 ? 0 : view->get_fov());
}
void
FGViewMgr::setFOV_deg (double fov)
{
FGViewer * view = get_current_view();
if (view != 0)
view->set_fov(fov);
}
double
FGViewMgr::getARM_deg () const
{
const FGViewer * view = get_current_view();
return (view == 0 ? 0 : view->get_aspect_ratio_multiplier());
}
void
FGViewMgr::setARM_deg (double aspect_ratio_multiplier)
{
FGViewer * view = get_current_view();
if (view != 0)
view->set_aspect_ratio_multiplier(aspect_ratio_multiplier);
}
double
FGViewMgr::getNear_m () const
{
const FGViewer * view = get_current_view();
return (view == 0 ? 0.5f : view->getNear_m());
}
void
FGViewMgr::setNear_m (double near_m)
{
FGViewer * view = get_current_view();
if (view != 0)
view->setNear_m(near_m);
}
void
FGViewMgr::setViewAxisLong (double axis)
{
axis_long = axis;
}
void
FGViewMgr::setViewAxisLat (double axis)
{
axis_lat = axis;
}
void
FGViewMgr::do_axes ()
{
// Take no action when hat is centered
if ( ( axis_long < 0.01 ) &&
( axis_long > -0.01 ) &&
( axis_lat < 0.01 ) &&
( axis_lat > -0.01 )
)
return;
double viewDir = 999;
/* Do all the quick and easy cases */
if (axis_long < 0) { // Longitudinal axis forward
if (axis_lat == axis_long)
viewDir = fgGetDouble("/sim/view/config/front-left-direction-deg");
else if (axis_lat == - axis_long)
viewDir = fgGetDouble("/sim/view/config/front-right-direction-deg");
else if (axis_lat == 0)
viewDir = fgGetDouble("/sim/view/config/front-direction-deg");
} else if (axis_long > 0) { // Longitudinal axis backward
if (axis_lat == - axis_long)
viewDir = fgGetDouble("/sim/view/config/back-left-direction-deg");
else if (axis_lat == axis_long)
viewDir = fgGetDouble("/sim/view/config/back-right-direction-deg");
else if (axis_lat == 0)
viewDir = fgGetDouble("/sim/view/config/back-direction-deg");
} else if (axis_long == 0) { // Longitudinal axis neutral
if (axis_lat < 0)
viewDir = fgGetDouble("/sim/view/config/left-direction-deg");
else if (axis_lat > 0)
viewDir = fgGetDouble("/sim/view/config/right-direction-deg");
else return; /* And assertion failure maybe? */
}
// Do all the difficult cases
if ( viewDir > 900 )
viewDir = SGD_RADIANS_TO_DEGREES * atan2 ( -axis_lat, -axis_long );
if ( viewDir < -1 ) viewDir += 360;
get_current_view()->setGoalHeadingOffset_deg(viewDir);
}