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Mathias FROEHLICH:

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remove a hack and do it properly: if the requested elevation is for some
reason below the surface and the intersection test fails (as it appears
to be the case in EGLL), try again from 10000m ASL

mf: typos
This commit is contained in:
mfranz 2005-12-04 10:43:49 +00:00
parent 72f46a4a6f
commit 435d874e35
2 changed files with 46 additions and 18 deletions
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48
src/FDM/flight.cxx
View file

@ -196,6 +196,10 @@ FGInterface::common_init ()
double alt_m = alt_ft * SG_FEET_TO_METER;
set_Longitude( lon );
set_Latitude( lat );
SG_LOG( SG_FLIGHT, SG_INFO, "Checking for lon = "
<< lon*SGD_RADIANS_TO_DEGREES << "deg, lat = "
<< lat*SGD_RADIANS_TO_DEGREES << "deg, alt = "
<< alt_ft << "ft");
double ground_elev_m = get_groundlevel_m(lat, lon, alt_m);
double ground_elev_ft = ground_elev_m * SG_METER_TO_FEET;
@ -894,26 +898,50 @@ FGInterface::get_agl_ft(double t, const double pt[3], double max_altoff,
double
FGInterface::get_groundlevel_m(double lat, double lon, double alt)
{
// First compute the sea level radius,
sgdVec3 pos, cpos;
sgGeodToCart(lat, lon, 0, pos);
double slr = sgdLengthVec3(pos);
// .. then the cartesian position of the given lat/lon/alt.
// Compute the cartesian position of the given lat/lon/alt.
sgGeodToCart(lat, lon, alt, pos);
// FIXME: how to handle t - ref_time differences ???
double ref_time, radius;
// Prepare the ground cache for that position.
if (!is_valid_m(&ref_time, cpos, &radius))
prepare_ground_cache_m(ref_time, pos, 10);
else if (radius*radius <= sgdDistanceSquaredVec3(pos, cpos))
prepare_ground_cache_m(ref_time, pos, radius);
if (!is_valid_m(&ref_time, cpos, &radius)) {
bool ok = prepare_ground_cache_m(ref_time, pos, 10);
/// This is most likely the case when the given altitude is
/// too low, try with a new altitude of 10000m, that should be
/// sufficient to find a ground level below everywhere on our planet
if (!ok) {
sgGeodToCart(lat, lon, 10000, pos);
/// If there is still no ground, return sea level radius
if (!prepare_ground_cache_m(ref_time, pos, 10))
return 0;
}
} else if (radius*radius <= sgdDistanceSquaredVec3(pos, cpos)) {
/// We reuse the old radius value, but only if it is at least 10 Meters ..
if (!(10 < radius)) // Well this strange compare is nan safe
radius = 10;
bool ok = prepare_ground_cache_m(ref_time, pos, radius);
/// This is most likely the case when the given altitude is
/// too low, try with a new altitude of 10000m, that should be
/// sufficient to find a ground level below everywhere on our planet
if (!ok) {
sgGeodToCart(lat, lon, 10000, pos);
/// If there is still no ground, return sea level radius
if (!prepare_ground_cache_m(ref_time, pos, radius))
return 0;
}
}
double contact[3], normal[3], vel[3], lc, ff, agl;
int type;
// Ignore the return value here, since it just tells us if
// the returns stem from the groundcache or from the coarse
// computations below the groundcache. The contact point is still something
// valid, the normals and the other returns just contain some defaults.
get_agl_m(ref_time, pos, 2.0, contact, normal, vel, &type, &lc, &ff, &agl);
return sgdLengthVec3(contact) - slr;
Point3D geodPos = sgCartToGeod(Point3D(contact[0], contact[1], contact[2]));
return geodPos.elev();
}
bool

16
src/FDM/groundcache.cxx
View file

@ -202,7 +202,7 @@ FGGroundCache::extractGroundProperty( ssgLeaf* l )
{
// FIXME: Do more ...
// Idea: have a get_globals() function which knows about that stuff.
// Or most propably read that from a configuration file,
// Or most probably read that from a configuration file,
// from property tree or whatever ...
// Get ground dependent data.
@ -361,7 +361,7 @@ FGGroundCache::putSurfaceLeafIntoCache(const sgdSphere *sp,
sgdSubVec3(off, isectpoint, tmp);
// Only accept the altitude if the intersection point is below the
// ground cache midpoint
if (0 < sgdScalarProductVec3( off, down ) || !found_ground) {
if (0 < sgdScalarProductVec3( off, down )) {
found_ground = true;
sgdAddVec3(isectpoint, cache_center);
double this_radius = sgdLengthVec3(isectpoint);
@ -441,7 +441,7 @@ FGGroundCache::cache_fill(ssgBranch *branch, sgdMat4 xform,
if ( e->isAKindOf( ssgTypeBranch() ) ) {
ssgBranch *b = (ssgBranch *)e;
if ( b->isAKindOf( ssgTypeTransform() ) ) {
// Collect up the transfors required to reach that part of
// Collect up the transforms required to reach that part of
// the branch.
sgMat4 xform2;
sgMakeIdentMat4( xform2 );
@ -458,9 +458,9 @@ FGGroundCache::cache_fill(ssgBranch *branch, sgdMat4 xform,
// This will minimize the number of vertices/triangles in the cache.
else if (e->isAKindOf(ssgTypeLeaf())) {
// Since we reach that leaf if we have an intersection with the
// most propably bigger wire/catapult cache sphere, we need to check
// most probably bigger wire/catapult cache sphere, we need to check
// that here, if the smaller cache for the surface has a chance for hits.
// Also, if the spheres do not intersect compute a croase agl value
// Also, if the spheres do not intersect compute a coarse agl value
// by following the line downwards originating at the aircraft.
bool spIsec = sp->intersects(&esphere);
putSurfaceLeafIntoCache(sp, xform, spIsec, down, (ssgLeaf *)e);
@ -493,7 +493,7 @@ FGGroundCache::prepare_ground_cache(double ref_time, const double pt[3],
// Decide where we put the scenery center.
Point3D old_cntr = globals->get_scenery()->get_center();
Point3D cntr(pt[0], pt[1], pt[2]);
// Only move the cache center if it is unaccaptable far away.
// Only move the cache center if it is unacceptable far away.
if (40*40 < old_cntr.distance3Dsquared(cntr))
globals->get_scenery()->set_center(cntr);
else
@ -523,7 +523,7 @@ FGGroundCache::prepare_ground_cache(double ref_time, const double pt[3],
sgdSetVec3(down, -pt[0], -pt[1], -pt[2]);
sgdNormalizeVec3(down);
// We collaps all transforms we need to reach a particular leaf.
// We collapse all transforms we need to reach a particular leaf.
// The leafs itself will be then transformed later.
// So our cache is just flat.
// For leafs which are moving (carriers surface, etc ...)
@ -736,7 +736,7 @@ bool FGGroundCache::caught_wire(double t, const double pt[4][3])
sgdCopyVec3( tri[1][2], pt[3] );
// Intersect the wire lines with each of these triangles.
// You have cautght a wire if they intersect.
// You have caught a wire if they intersect.
for (size_t i = 0; i < sz; ++i) {
sgdVec3 le[2];
for (int k = 0; k < 2; ++k) {