void
MapItemListBuilder::AddArrivalAltitudes(
const ProtectedRoutePlanner &route_planner,
const RasterTerrain *terrain, fixed safety_height)
{
if (list.full())
return;
// Calculate terrain elevation if possible
short elevation;
if (terrain != NULL)
elevation = terrain->GetTerrainHeight(location);
else
elevation = RasterBuffer::TERRAIN_INVALID;
// Calculate target altitude
RoughAltitude safety_elevation(safety_height);
if (!RasterBuffer::IsInvalid(elevation))
safety_elevation += RoughAltitude(elevation);
// Save destination point incl. elevation and safety height
const AGeoPoint destination(location, safety_elevation);
// Calculate arrival altitudes
ReachResult reach;
ProtectedRoutePlanner::Lease leased_route_planner(route_planner);
if (!leased_route_planner->FindPositiveArrival(destination, reach))
return;
reach.Subtract(RoughAltitude(safety_height));
list.append(new ArrivalAltitudeMapItem(RoughAltitude(elevation), reach));
}
int main(int argc, char** argv) {
const char hc_path[] = "tmp/terrain";
const char *map_path;
if ((argc<2) || !strlen(argv[0])) {
map_path = hc_path;
} else {
map_path = argv[0];
}
TCHAR jp2_path[4096];
_tcscpy(jp2_path, PathName(map_path));
_tcscat(jp2_path, _T(DIR_SEPARATOR_S) _T("terrain.jp2"));
TCHAR j2w_path[4096];
_tcscpy(j2w_path, PathName(map_path));
_tcscat(j2w_path, _T(DIR_SEPARATOR_S) _T("terrain.j2w"));
NullOperationEnvironment operation;
RasterMap map(jp2_path, j2w_path, NULL, operation);
do {
map.SetViewCenter(map.GetMapCenter(), fixed(100000));
} while (map.IsDirty());
plan_tests(16*3);
test_troute(map, fixed(0), fixed(0.1), RoughAltitude(10000));
test_troute(map, fixed(0), fixed(0), RoughAltitude(10000));
test_troute(map, fixed(5.0), fixed(1), RoughAltitude(10000));
return exit_status();
}
static void test_reach(const RasterMap& map, fixed mwind, fixed mc)
{
GlideSettings settings;
settings.SetDefaults();
GlidePolar polar(mc);
SpeedVector wind(Angle::Degrees(0), mwind);
TerrainRoute route;
route.UpdatePolar(settings, polar, polar, wind);
route.SetTerrain(&map);
GeoPoint origin(map.GetMapCenter());
fixed pd = map.PixelDistance(origin, 1);
printf("# pixel size %g\n", (double)pd);
bool retval= true;
short horigin = map.GetHeight(origin)+1000;
AGeoPoint aorigin(origin, RoughAltitude(horigin));
RoutePlannerConfig config;
config.SetDefaults();
retval = route.SolveReach(aorigin, config, RoughAltitude::Max());
ok(retval, "reach solve", 0);
PrintHelper::print_reach_tree(route);
GeoPoint dest(origin.longitude-Angle::Degrees(0.02),
origin.latitude-Angle::Degrees(0.02));
{
Directory::Create(_T("output/results"));
std::ofstream fout("output/results/terrain.txt");
unsigned nx = 100;
unsigned ny = 100;
for (unsigned i=0; i< nx; ++i) {
for (unsigned j=0; j< ny; ++j) {
fixed fx = (fixed)i / (nx - 1) * 2 - fixed(1);
fixed fy = (fixed)j / (ny - 1) * 2 - fixed(1);
GeoPoint x(origin.longitude + Angle::Degrees(fixed(0.6) * fx),
origin.latitude + Angle::Degrees(fixed(0.6) * fy));
short h = map.GetInterpolatedHeight(x);
AGeoPoint adest(x, RoughAltitude(h));
ReachResult reach;
route.FindPositiveArrival(adest, reach);
if ((i % 5 == 0) && (j % 5 == 0)) {
AGeoPoint ao2(x, RoughAltitude(h + 1000));
route.SolveReach(ao2, config, RoughAltitude::Max());
}
fout << x.longitude.Degrees() << " "
<< x.latitude.Degrees() << " "
<< h << " " << (int)reach.terrain << "\n";
}
fout << "\n";
}
fout << "\n";
}
}
bool
ReachFan::FindPositiveArrival(const AGeoPoint dest, const RoutePolars &rpolars,
ReachResult &result_r) const
{
if (root.IsEmpty())
return false;
const FlatGeoPoint d(task_proj.ProjectInteger(dest));
const ReachFanParms parms(rpolars, task_proj, (int)terrain_base);
result_r.Clear();
// first calculate direct (terrain-independent height)
result_r.direct = root.DirectArrival(d, parms);
if (root.IsDummy())
/* terrain reach is not available, stop here */
return true;
// if can't reach even with no terrain, exit early
if (std::min(root.GetHeight(), result_r.direct) < dest.altitude) {
result_r.terrain = result_r.direct;
result_r.terrain_valid = ReachResult::Validity::UNREACHABLE;
return true;
}
// now calculate turning solution
result_r.terrain = dest.altitude - RoughAltitude(1);
result_r.terrain_valid = root.FindPositiveArrival(d, parms, result_r.terrain)
? ReachResult::Validity::VALID
: ReachResult::Validity::UNREACHABLE;
return true;
}
bool
FlatTriangleFanTree::CheckGap(const AFlatGeoPoint &n, const RouteLink &e_1,
const RouteLink &e_2, ReachFanParms &parms)
{
const bool side = (e_1.d > e_2.d);
const RouteLink &e_long = (side ? e_1 : e_2);
const RouteLink &e_short = (side ? e_2 : e_1);
if (e_short.d >= e_long.d)
return false;
const FlatGeoPoint &p_long = (side ? e_1.first : e_2.first);
// return true if this gap was caught (applicable) whether or not it generated
// a change
const fixed f0 = e_short.d * e_long.inv_d;
const RoughAltitude h_loss =
parms.rpolars.CalcGlideArrival(n, p_long, parms.task_proj) - n.altitude;
const FlatGeoPoint dp(p_long - n);
// scan from n-p_long to perpendicular to n-p_long
int index_left, index_right;
if (!side) {
index_left = e_long.polar_index - REACH_SWEEP;
index_right = e_long.polar_index - REACH_BUFFER;
} else {
index_left = e_long.polar_index + REACH_BUFFER;
index_right = e_long.polar_index + REACH_SWEEP;
}
children.emplace_back(depth + 1);
FlatTriangleFanTree &child = children.back();
for (fixed f = f0; f < fixed(0.9); f += fixed(0.1)) {
// find corner point
const FlatGeoPoint px = (dp * f + n);
// position x is length (n to p_short) along (n to p_long)
const RoughAltitude h = n.altitude + RoughAltitude(f * h_loss);
// altitude calculated from pure glide from n to x
const AFlatGeoPoint x(px, h);
child.FillReach(x, index_left, index_right, parms);
// prune child if empty or single spike
if (child.vs.size() > 3) {
parms.vertex_counter += child.vs.size();
parms.fan_counter++;
return true;
}
child.vs.clear();
}
// don't need the child
children.pop_back();
return false;
}
RoughAltitude
RoutePolars::CalcGlideArrival(const AFlatGeoPoint& origin,
const FlatGeoPoint& dest,
const TaskProjection& proj) const
{
const RouteLink e(RoutePoint(dest, RoughAltitude(0)), origin, proj);
return origin.altitude - CalcVHeight(e);
}
void visit_abstract(const AbstractAirspace &as) {
assert(!m_intersections.empty());
GeoPoint point = m_intersections[0].first;
RouteLink l = rpolar.GenerateIntermediate(link.first,
RoutePoint(proj.project(point), link.second.altitude),
proj);
if (l.second.altitude < RoughAltitude(as.GetBase().altitude) ||
l.second.altitude > RoughAltitude(as.GetTop().altitude))
return;
if (negative(min_distance) || (l.d < min_distance)) {
min_distance = l.d;
nearest = std::make_pair(&as, l.second);
}
}
int main(int argc, char** argv) {
static const char hc_path[] = "tmp/map.xcm";
const char *map_path;
if ((argc<2) || !strlen(argv[0])) {
map_path = hc_path;
} else {
map_path = argv[0];
}
ZZIP_DIR *dir = zzip_dir_open(map_path, nullptr);
if (dir == nullptr) {
fprintf(stderr, "Failed to open %s\n", map_path);
return EXIT_FAILURE;
}
RasterMap map;
NullOperationEnvironment operation;
if (!LoadTerrainOverview(dir, map.GetTileCache(),
operation)) {
fprintf(stderr, "failed to load map\n");
zzip_dir_close(dir);
return EXIT_FAILURE;
}
SharedMutex mutex;
do {
UpdateTerrainTiles(dir, map.GetTileCache(), mutex,
map.GetProjection(),
map.GetMapCenter(), fixed(100000));
} while (map.IsDirty());
zzip_dir_close(dir);
plan_tests(16*3);
test_troute(map, fixed(0), fixed(0.1), RoughAltitude(10000));
test_troute(map, fixed(0), fixed(0), RoughAltitude(10000));
test_troute(map, fixed(5.0), fixed(1), RoughAltitude(10000));
return exit_status();
}
void
FlatTriangleFanTree::FillGaps(const AFlatGeoPoint &origin, ReachFanParms &parms)
{
// worth checking for gaps?
if (vs.size() > 2 && parms.rpolars.IsTurningReachEnabled()) {
// now check gaps
const RoutePoint o(origin, RoughAltitude(0));
RouteLink e_last(RoutePoint(*vs.begin(), RoughAltitude(0)),
o, parms.task_proj);
for (auto x_last = vs.cbegin(), end = vs.cend(),
x = x_last + 1; x != end; x_last = x++) {
if (TooClose(*x, origin) || TooClose(*x_last, origin))
continue;
const RouteLink e(RoutePoint(*x, RoughAltitude(0)), o, parms.task_proj);
// check if children need to be added
CheckGap(origin, e_last, e, parms);
e_last = e;
}
}
}
gcc_pure
NearestAirspace
NearestAirspace::FindHorizontal(const MoreData &basic,
const ProtectedAirspaceWarningManager &airspace_warnings,
const Airspaces &airspace_database)
{
if (!basic.location_available)
/* can't check for airspaces without a GPS fix */
return NearestAirspace();
/* find the nearest airspace */
//consider only active airspaces
const WrapAirspacePredicate<ActiveAirspacePredicate> active_predicate(&airspace_warnings);
const WrapAirspacePredicate<OutsideAirspacePredicate> outside_predicate(AGeoPoint(basic.location, RoughAltitude(0)));
const AndAirspacePredicate outside_and_active_predicate(active_predicate, outside_predicate);
const Airspace *airspace;
//if altitude is available, filter airspaces in same height as airplane
if (basic.NavAltitudeAvailable()) {
/* check altitude; hard-coded margin of 50m (for now) */
WrapAirspacePredicate<AirspacePredicateHeightRange> height_range_predicate(RoughAltitude(basic.nav_altitude-fixed(50)),
RoughAltitude(basic.nav_altitude+fixed(50)));
AndAirspacePredicate and_predicate(outside_and_active_predicate, height_range_predicate);
airspace = airspace_database.FindNearest(basic.location, and_predicate);
} else //only filter outside and active
airspace = airspace_database.FindNearest(basic.location, outside_and_active_predicate);
if (airspace == nullptr)
return NearestAirspace();
const AbstractAirspace &as = airspace->GetAirspace();
/* calculate distance to the nearest point */
const GeoPoint closest = as.ClosestPoint(basic.location,
airspace_database.GetProjection());
return NearestAirspace(as, basic.location.Distance(closest));
}
bool
RoutePolars::CheckClearance(const RouteLink &e, const RasterMap* map,
const TaskProjection &proj, RoutePoint& inp) const
{
if (!config.IsTerrainEnabled())
return true;
GeoPoint int_x;
int int_h;
GeoPoint start = proj.Unproject(e.first);
GeoPoint dest = proj.Unproject(e.second);
assert(map);
if (!map->FirstIntersection(start, (int)e.first.altitude, dest,
(int)e.second.altitude, (int)CalcVHeight(e),
(int)climb_ceiling, (int)GetSafetyHeight(),
int_x, int_h))
return true;
inp = RoutePoint(proj.ProjectInteger(int_x), RoughAltitude(int_h));
return false;
}
unsigned
RoutePolars::CalcTime(const RouteLink& link) const
{
const RoughAltitude dh = link.second.altitude - link.first.altitude;
if (dh.IsNegative() && !positive(inv_mc))
// impossible, can't climb
return UINT_MAX;
// dh/d = gradient
const fixed rho = dh.IsPositive() ?
std::min(fixed(1), (dh * link.inv_d *
polar_glide.GetPoint(link.polar_index).inv_gradient)) :
fixed(0);
if ((rho < fixed(1)) && !polar_cruise.GetPoint(link.polar_index).valid)
// impossible, can't cruise
return UINT_MAX;
if (positive(rho) && !polar_glide.GetPoint(link.polar_index).valid)
// impossible, can't glide
return UINT_MAX;
const int t_cruise = (int)(
link.d * (rho * polar_glide.GetPoint(link.polar_index).slowness +
(fixed(1) - rho) * polar_cruise.GetPoint(link.polar_index).slowness));
if (link.second.altitude > cruise_altitude) {
// penalise any climbs required above cruise altitude
const RoughAltitude h_penalty = std::max(
RoughAltitude(0),
link.second.altitude - std::max(cruise_altitude, link.first.altitude));
return t_cruise + (int)(h_penalty * inv_mc);
}
return t_cruise;
}
static bool
test_route(const unsigned n_airspaces, const RasterMap& map)
{
Airspaces airspaces;
setup_airspaces(airspaces, map.GetMapCenter(), n_airspaces);
{
std::ofstream fout("results/terrain.txt");
unsigned nx = 100;
unsigned ny = 100;
GeoPoint origin(map.GetMapCenter());
for (unsigned i = 0; i < nx; ++i) {
for (unsigned j = 0; j < ny; ++j) {
fixed fx = (fixed)i / (nx - 1) * fixed(2.0) - fixed_one;
fixed fy = (fixed)j / (ny - 1) * fixed(2.0) - fixed_one;
GeoPoint x(origin.longitude + Angle::Degrees(fixed(0.2) + fixed(0.7) * fx),
origin.latitude + Angle::Degrees(fixed(0.9) * fy));
short h = map.GetInterpolatedHeight(x);
fout << x.longitude.Degrees() << " " << x.latitude.Degrees()
<< " " << h << "\n";
}
fout << "\n";
}
fout << "\n";
}
{
// local scope, see what happens when we go out of scope
GeoPoint p_start(Angle::Degrees(fixed(-0.3)), Angle::Degrees(fixed(0.0)));
p_start += map.GetMapCenter();
GeoPoint p_dest(Angle::Degrees(fixed(0.8)), Angle::Degrees(fixed(-0.7)));
p_dest += map.GetMapCenter();
AGeoPoint loc_start(p_start, RoughAltitude(map.GetHeight(p_start) + 100));
AGeoPoint loc_end(p_dest, RoughAltitude(map.GetHeight(p_dest) + 100));
AircraftState state;
GlidePolar glide_polar(fixed(0.1));
AirspaceAircraftPerformanceGlide perf(glide_polar);
GeoVector vec(loc_start, loc_end);
fixed range = fixed(10000) + vec.distance / 2;
state.location = loc_start;
state.altitude = loc_start.altitude;
{
Airspaces as_route(airspaces, false);
// dummy
// real one, see if items changed
as_route.synchronise_in_range(airspaces, vec.MidPoint(loc_start), range);
int size_1 = as_route.size();
if (verbose)
printf("# route airspace size %d\n", size_1);
as_route.synchronise_in_range(airspaces, vec.MidPoint(loc_start), fixed_one);
int size_2 = as_route.size();
if (verbose)
printf("# route airspace size %d\n", size_2);
ok(size_2 < size_1, "shrink as", 0);
// go back
as_route.synchronise_in_range(airspaces, vec.MidPoint(loc_end), range);
int size_3 = as_route.size();
if (verbose)
printf("# route airspace size %d\n", size_3);
ok(size_3 >= size_2, "grow as", 0);
// and again
as_route.synchronise_in_range(airspaces, vec.MidPoint(loc_start), range);
int size_4 = as_route.size();
if (verbose)
printf("# route airspace size %d\n", size_4);
ok(size_4 >= size_3, "grow as", 0);
scan_airspaces(state, as_route, perf, true, loc_end);
}
// try the solver
SpeedVector wind(Angle::Degrees(fixed(0)), fixed(0.0));
GlidePolar polar(fixed_one);
GlideSettings settings;
settings.SetDefaults();
AirspaceRoute route(airspaces);
route.UpdatePolar(settings, polar, polar, wind);
route.SetTerrain(&map);
RoutePlannerConfig config;
config.mode = RoutePlannerConfig::Mode::BOTH;
bool sol = false;
for (int i = 0; i < NUM_SOL; i++) {
loc_end.latitude += Angle::Degrees(fixed(0.1));
loc_end.altitude = map.GetHeight(loc_end) + 100;
route.Synchronise(airspaces, loc_start, loc_end);
if (route.Solve(loc_start, loc_end, config)) {
sol = true;
if (verbose) {
PrintHelper::print_route(route);
}
} else {
if (verbose) {
printf("# fail\n");
}
sol = false;
}
char buffer[80];
sprintf(buffer, "route %d solution", i);
ok(sol, buffer, 0);
}
}
return true;
}
gcc_constexpr_method
RoughAltitude operator+(const RoughAltitude other) const {
return RoughAltitude(value + other.value);
}
/**
* Create a representation of the largest possible value.
*/
gcc_constexpr_function
static RoughAltitude Max() {
return RoughAltitude((short)SHRT_MAX);
}
/**
* Create a representation of the largest possible value.
*/
constexpr
static RoughAltitude Max() {
return RoughAltitude((short)SHRT_MAX);
}
constexpr
RoughAltitude operator-(const RoughAltitude other) const {
return RoughAltitude(value - other.value);
}
RoughAltitude GetSafetyHeight() const {
return RoughAltitude(config.safety_height_terrain);
}
static void
test_troute(const RasterMap& map, fixed mwind, fixed mc, RoughAltitude ceiling)
{
GlideSettings settings;
settings.SetDefaults();
GlidePolar polar(mc);
SpeedVector wind(Angle::Degrees(0), mwind);
TerrainRoute route;
route.UpdatePolar(settings, polar, polar, wind);
route.SetTerrain(&map);
GeoPoint origin(map.GetMapCenter());
fixed pd = map.PixelDistance(origin, 1);
printf("# pixel size %g\n", (double)pd);
bool retval= true;
{
Directory::Create(_T("output/results"));
std::ofstream fout ("output/results/terrain.txt");
unsigned nx = 100;
unsigned ny = 100;
for (unsigned i=0; i< nx; ++i) {
for (unsigned j=0; j< ny; ++j) {
fixed fx = (fixed)i / (nx - 1) * 2 - fixed(1);
fixed fy = (fixed)j / (ny - 1) * 2 - fixed(1);
GeoPoint x(origin.longitude + Angle::Degrees(fixed(0.6) * fx),
origin.latitude + Angle::Degrees(fixed(0.4) * fy));
short h = map.GetInterpolatedHeight(x);
fout << x.longitude.Degrees() << " " << x.latitude.Degrees() << " " << h << "\n";
}
fout << "\n";
}
fout << "\n";
}
RoutePlannerConfig config;
config.mode = RoutePlannerConfig::Mode::BOTH;
unsigned i=0;
for (fixed ang = fixed(0); ang < fixed_two_pi; ang += fixed(M_PI / 8)) {
GeoPoint dest = GeoVector(fixed(40000.0), Angle::Radians(ang)).EndPoint(origin);
short hdest = map.GetHeight(dest)+100;
retval = route.Solve(AGeoPoint(origin,
RoughAltitude(map.GetHeight(origin) + 100)),
AGeoPoint(dest,
RoughAltitude(positive(mc)
? hdest
: std::max(hdest, (short)3200))),
config, ceiling);
char buffer[80];
sprintf(buffer,"terrain route solve, dir=%g, wind=%g, mc=%g ceiling=%d",
(double)ang, (double)mwind, (double)mc, (int)ceiling);
ok(retval, buffer, 0);
PrintHelper::print_route(route);
i++;
}
// polar.SetMC(fixed(0));
// route.UpdatePolar(polar, wind);
}
bool
AirspacePredicateHeightRange::check_height(const AbstractAirspace& t) const
{
return RoughAltitude(t.GetTop().altitude) >= h_min &&
RoughAltitude(t.GetBase().altitude) <= h_max;
}
void
FlarmComputer::Process(FlarmData &flarm, const FlarmData &last_flarm,
const NMEAInfo &basic)
{
// Cleanup old calculation instances
if (basic.time_available)
flarm_calculations.CleanUp(basic.time);
// if (FLARM data is available)
if (!flarm.IsDetected())
return;
double north_to_latitude(0);
double east_to_longitude(0);
if (basic.location_available) {
// Precalculate relative east and north projection to lat/lon
// for Location calculations of each target
constexpr Angle delta_lat = Angle::Degrees(0.01);
constexpr Angle delta_lon = Angle::Degrees(0.01);
GeoPoint plat = basic.location;
plat.latitude += delta_lat;
GeoPoint plon = basic.location;
plon.longitude += delta_lon;
double dlat = basic.location.DistanceS(plat);
double dlon = basic.location.DistanceS(plon);
if (fabs(dlat) > 0 && fabs(dlon) > 0) {
north_to_latitude = delta_lat.Degrees() / dlat;
east_to_longitude = delta_lon.Degrees() / dlon;
}
}
// for each item in traffic
for (auto &traffic : flarm.traffic.list) {
// if we don't know the target's name yet
if (!traffic.HasName()) {
// lookup the name of this target's id
const TCHAR *fname = FlarmDetails::LookupCallsign(traffic.id);
if (fname != NULL)
traffic.name = fname;
}
// Calculate distance
traffic.distance = hypot(traffic.relative_north, traffic.relative_east);
// Calculate Location
traffic.location_available = basic.location_available;
if (traffic.location_available) {
traffic.location.latitude =
Angle::Degrees(traffic.relative_north * north_to_latitude) +
basic.location.latitude;
traffic.location.longitude =
Angle::Degrees(traffic.relative_east * east_to_longitude) +
basic.location.longitude;
}
// Calculate absolute altitude
traffic.altitude_available = basic.gps_altitude_available;
if (traffic.altitude_available)
traffic.altitude = traffic.relative_altitude + RoughAltitude(basic.gps_altitude);
// Calculate average climb rate
traffic.climb_rate_avg30s_available = traffic.altitude_available;
if (traffic.climb_rate_avg30s_available)
traffic.climb_rate_avg30s =
flarm_calculations.Average30s(traffic.id, basic.time, traffic.altitude);
// The following calculations are only relevant for targets
// where information is missing
if (traffic.track_received && traffic.turn_rate_received &&
traffic.speed_received && traffic.climb_rate_received)
continue;
// Check if the target has been seen before in the last seconds
const FlarmTraffic *last_traffic =
last_flarm.traffic.FindTraffic(traffic.id);
if (last_traffic == NULL || !last_traffic->valid)
continue;
// Calculate the time difference between now and the last contact
double dt = traffic.valid.GetTimeDifference(last_traffic->valid);
if (dt > 0) {
// Calculate the immediate climb rate
if (!traffic.climb_rate_received)
traffic.climb_rate =
(traffic.relative_altitude - last_traffic->relative_altitude) / dt;
} else {
// Since the time difference is zero (or negative)
// we can just copy the old values
if (!traffic.climb_rate_received)
traffic.climb_rate = last_traffic->climb_rate;
}
if (dt > 0 &&
traffic.location_available &&
last_traffic->location_available) {
// Calculate the GeoVector between now and the last contact
GeoVector vec = last_traffic->location.DistanceBearing(traffic.location);
if (!traffic.track_received)
traffic.track = vec.bearing;
// Calculate the turn rate
if (!traffic.turn_rate_received) {
Angle turn_rate = traffic.track - last_traffic->track;
traffic.turn_rate =
turn_rate.AsDelta().Degrees() / dt;
}
// Calculate the speed [m/s]
if (!traffic.speed_received)
traffic.speed = vec.distance / dt;
} else {
// Since the time difference is zero (or negative)
// we can just copy the old values
if (!traffic.track_received)
traffic.track = last_traffic->track;
if (!traffic.turn_rate_received)
traffic.turn_rate = last_traffic->turn_rate;
if (!traffic.speed_received)
traffic.speed = last_traffic->speed;
}
}
}
RoughAltitude
RoutePolars::CalcVHeight(const RouteLink &link) const
{
return RoughAltitude(polar_glide.GetPoint(link.polar_index).gradient * link.d);
}
TerrainRoute::TerrainRoute():
m_inx_terrain(0, 0, RoughAltitude(0))
{
}