#include <float.h>
-#include <plib/sg.h>
#include <osg/CullFace>
#include <osg/Drawable>
#include <osg/Geode>
#include "flight.hxx"
#include "groundcache.hxx"
+/// Ok, variant that uses a infinite line istead of the ray.
+/// also not that this only works if the ray direction is normalized.
static inline bool
-fgdRayTriangle(SGVec3d& x, const SGVec3d& point, const SGVec3d& dir,
- const SGVec3d v[3])
+intersectsInf(const SGRayd& ray, const SGSphered& sphere)
{
- double eps = 1e-4;
- // Method based on the observation that we are looking for a
- // point x that can be expressed in terms of the triangle points
- // x = p_0 + \mu_1*(p_1 - p_0) + \mu_2*(p_2 - p_0)
- // with 0 <= \mu_1, \mu_2 and \mu_1 + \mu_2 <= 1.
- // OTOH it could be expressed in terms of the ray
- // x = point + \lambda*dir
- // Now we can compute \mu_i and \lambda.
- // define
- SGVec3d d1 = v[1] - v[0];
- SGVec3d d2 = v[2] - v[0];
- SGVec3d b = point - v[0];
-
- // the vector in normal direction, but not normalized
- SGVec3d d1crossd2 = cross(d1, d2);
-
- double denom = -dot(dir, d1crossd2);
- double signDenom = copysign(1, denom);
- // return if paralell ??? FIXME what if paralell and in plane?
- // may be we are ok below than anyway??
- // if (SGMiscd::abs(denom) <= SGLimitsd::min())
- // return false;
-
- // Now \lambda would read
- // lambda = 1/denom*dot(b, d1crossd2);
- // To avoid an expensive division we multiply by |denom|
- double lambdaDenom = signDenom*dot(b, d1crossd2);
- if (lambdaDenom < 0)
- return false;
- // For line segment we would test against
- // if (1 < lambda)
- // return false;
- // with the original lambda. The multiplied test would read
- // if (absDenom < lambdaDenom)
- // return false;
-
- double absDenom = fabs(denom);
- double absDenomEps = absDenom*eps;
-
- SGVec3d bcrossr = cross(b, dir);
- // double mu1 = 1/denom*dot(d2, bcrossr);
- double mu1 = signDenom*dot(d2, bcrossr);
- if (mu1 < -absDenomEps)
- return false;
- // double mu2 = -1/denom*dot(d1, bcrossr);
- // if (mu2 < -eps)
- // return false;
- double mmu2 = signDenom*dot(d1, bcrossr);
- if (mmu2 > absDenomEps)
- return false;
-
- if (mu1 - mmu2 > absDenom + absDenomEps)
- return false;
-
- x = point;
- // if we have survived here it could only happen with denom == 0
- // that the point is already in plane. Then return the origin ...
- if (SGLimitsd::min() < absDenom)
- x += (lambdaDenom/absDenom)*dir;
-
- return true;
-}
-
-static inline bool
-fgdPointInTriangle( const SGVec3d& point, const SGVec3d tri[3] )
-{
- SGVec3d dif;
-
- // Some tolerance in meters we accept a point to be outside of the triangle
- // and still return that it is inside.
- SGDfloat min, max;
- // punt if outside bouding cube
- SG_MIN_MAX3 ( min, max, tri[0][0], tri[1][0], tri[2][0] );
- if( (point[0] < min) || (point[0] > max) )
- return false;
- dif[0] = max - min;
-
- SG_MIN_MAX3 ( min, max, tri[0][1], tri[1][1], tri[2][1] );
- if( (point[1] < min) || (point[1] > max) )
- return false;
- dif[1] = max - min;
-
- SG_MIN_MAX3 ( min, max, tri[0][2], tri[1][2], tri[2][2] );
- if( (point[2] < min) || (point[2] > max) )
- return false;
- dif[2] = max - min;
-
- // drop the smallest dimension so we only have to work in 2d.
- SGDfloat min_dim = SG_MIN3 (dif[0], dif[1], dif[2]);
- SGDfloat x1, y1, x2, y2, x3, y3, rx, ry;
- if ( fabs(min_dim-dif[0]) <= DBL_EPSILON ) {
- // x is the smallest dimension
- x1 = point[1];
- y1 = point[2];
- x2 = tri[0][1];
- y2 = tri[0][2];
- x3 = tri[1][1];
- y3 = tri[1][2];
- rx = tri[2][1];
- ry = tri[2][2];
- } else if ( fabs(min_dim-dif[1]) <= DBL_EPSILON ) {
- // y is the smallest dimension
- x1 = point[0];
- y1 = point[2];
- x2 = tri[0][0];
- y2 = tri[0][2];
- x3 = tri[1][0];
- y3 = tri[1][2];
- rx = tri[2][0];
- ry = tri[2][2];
- } else if ( fabs(min_dim-dif[2]) <= DBL_EPSILON ) {
- // z is the smallest dimension
- x1 = point[0];
- y1 = point[1];
- x2 = tri[0][0];
- y2 = tri[0][1];
- x3 = tri[1][0];
- y3 = tri[1][1];
- rx = tri[2][0];
- ry = tri[2][1];
- } else {
- // all dimensions are really small so lets call it close
- // enough and return a successful match
- return true;
- }
-
- // check if intersection point is on the same side of p1 <-> p2 as p3
- SGDfloat tmp = (y2 - y3);
- SGDfloat tmpn = (x2 - x3);
- int side1 = SG_SIGN (tmp * (rx - x3) + (y3 - ry) * tmpn);
- int side2 = SG_SIGN (tmp * (x1 - x3) + (y3 - y1) * tmpn);
- if ( side1 != side2 ) {
- // printf("failed side 1 check\n");
- return false;
- }
-
- // check if intersection point is on correct side of p2 <-> p3 as p1
- tmp = (y3 - ry);
- tmpn = (x3 - rx);
- side1 = SG_SIGN (tmp * (x2 - rx) + (ry - y2) * tmpn);
- side2 = SG_SIGN (tmp * (x1 - rx) + (ry - y1) * tmpn);
- if ( side1 != side2 ) {
- // printf("failed side 2 check\n");
- return false;
- }
-
- // check if intersection point is on correct side of p1 <-> p3 as p2
- tmp = (y2 - ry);
- tmpn = (x2 - rx);
- side1 = SG_SIGN (tmp * (x3 - rx) + (ry - y3) * tmpn);
- side2 = SG_SIGN (tmp * (x1 - rx) + (ry - y1) * tmpn);
- if ( side1 != side2 ) {
- // printf("failed side 3 check\n");
- return false;
- }
-
- return true;
-}
-
-// Test if the line given by the point on the line pt_on_line and the
-// line direction dir intersects the sphere sp.
-// Adapted from plib.
-static inline bool
-fgdIsectSphereInfLine(const SGVec3d& sphereCenter, double radius,
- const SGVec3d& pt_on_line, const SGVec3d& dir)
-{
- SGVec3d r = sphereCenter - pt_on_line;
- double projectedDistance = dot(r, dir);
+ SGVec3d r = sphere.getCenter() - ray.getOrigin();
+ double projectedDistance = dot(r, ray.getDirection());
double dist = dot(r, r) - projectedDistance * projectedDistance;
- return dist < radius*radius;
+ return dist < sphere.getRadius2();
}
template<typename T>
mGroundProperty.pivot = SGVec3d(0, 0, 0);
}
+ void setSceneryCenter(const SGVec3d& cntr)
+ {
+ mLocalToGlobal.makeTranslate(cntr.osg());
+ mGlobalToLocal.makeTranslate(-cntr.osg());
+ }
+
void updateCullMode(osg::StateSet* stateSet)
{
if (!stateSet)
// cats or wires
double rw = bs.radius() + mWireCacheRadius;
if (rw*rw < centerDist2 &&
- !fgdIsectSphereInfLine(cntr, bs.radius(), mCacheReference, mDown))
+ !intersectsInf(SGRayd(mCacheReference, mDown),
+ SGSphered(cntr, bs.radius())))
return false;
sphIsec = false;
}
// a bounding sphere in the node local system
SGVec3d boundCenter = (1.0/3)*(v[0] + v[1] + v[2]);
-#if 0
- double boundRadius = std::max(norm1(v[0] - boundCenter),
- norm1(v[1] - boundCenter));
- boundRadius = std::max(boundRadius, norm1(v[2] - boundCenter));
- // Ok, we take the 1-norm instead of the expensive 2 norm.
- // Therefore we need that scaling factor - roughly sqrt(3)
- boundRadius = 1.733*boundRadius;
-#else
double boundRadius = std::max(distSqr(v[0], boundCenter),
distSqr(v[1], boundCenter));
boundRadius = std::max(boundRadius, distSqr(v[2], boundCenter));
boundRadius = sqrt(boundRadius);
-#endif
+
+ SGRayd ray(mLocalCacheReference, mLocalDown);
// if we are not in the downward cylinder bail out
- if (!fgdIsectSphereInfLine(boundCenter, boundRadius + mCacheRadius,
- mLocalCacheReference, mLocalDown))
+ if (!intersectsInf(ray, SGSphered(boundCenter, boundRadius + mCacheRadius)))
return;
+ SGTriangled triangle(v);
// The normal and plane in the node local coordinate system
- SGVec3d n = normalize(cross(v[1] - v[0], v[2] - v[0]));
+ SGVec3d n = cross(triangle.getEdge(0), triangle.getEdge(1));
if (0 < dot(mLocalDown, n)) {
if (mBackfaceCulling) {
// Surface points downwards, ignore for altitude computations.
return;
} else {
- n = -n;
- std::swap(v[1], v[2]);
+ triangle.flip();
}
}
// Only check if the triangle is in the cache sphere if the plane
// containing the triangle is near enough
- if (sphIsec && fabs(dot(n, v[0] - mLocalCacheReference)) < mCacheRadius) {
- // Check if the sphere around the vehicle intersects the sphere
- // around that triangle. If so, put that triangle into the cache.
- double r2 = boundRadius + mCacheRadius;
- if (distSqr(boundCenter, mLocalCacheReference) < r2*r2) {
- FGGroundCache::Triangle t;
- for (unsigned i = 0; i < 3; ++i)
- t.vertices[i].osg() = v[i].osg()*mLocalToGlobal;
- t.boundCenter.osg() = boundCenter.osg()*mLocalToGlobal;
- t.boundRadius = boundRadius;
-
- SGVec3d tmp;
- tmp.osg() = osg::Matrixd::transform3x3(n.osg(), mLocalToGlobal);
- t.plane = SGVec4d(tmp[0], tmp[1], tmp[2], -dot(tmp, t.vertices[0]));
- t.velocity = mGroundProperty.vel;
- t.rotation = mGroundProperty.rot;
- t.rotation_pivot = mGroundProperty.pivot - mGroundCache->cache_center;
- t.type = mGroundProperty.type;
- t.material = mGroundProperty.material;
- mGroundCache->triangles.push_back(t);
+ if (sphIsec) {
+ double d = dot(n, v[0] - mLocalCacheReference);
+ if (d*d < mCacheRadius*dot(n, n)) {
+ // Check if the sphere around the vehicle intersects the sphere
+ // around that triangle. If so, put that triangle into the cache.
+ double r2 = boundRadius + mCacheRadius;
+ if (distSqr(boundCenter, mLocalCacheReference) < r2*r2) {
+ FGGroundCache::Triangle t;
+ t.triangle.setBaseVertex(SGVec3d(v[0].osg()*mLocalToGlobal));
+ t.triangle.setEdge(0, SGVec3d(osg::Matrixd::transform3x3(triangle.getEdge(0).osg(), mLocalToGlobal)));
+ t.triangle.setEdge(1, SGVec3d(osg::Matrixd::transform3x3(triangle.getEdge(1).osg(), mLocalToGlobal)));
+
+ t.sphere.setCenter(SGVec3d(boundCenter.osg()*mLocalToGlobal));
+ t.sphere.setRadius(boundRadius);
+
+ t.velocity = mGroundProperty.vel;
+ t.rotation = mGroundProperty.rot;
+ t.rotation_pivot = mGroundProperty.pivot;
+ t.type = mGroundProperty.type;
+ t.material = mGroundProperty.material;
+ mGroundCache->triangles.push_back(t);
+ }
}
}
// In case the cache is empty, we still provide agl computations.
// But then we use the old way of having a fixed elevation value for
// the whole lifetime of this cache.
- SGVec4d plane = SGVec4d(n[0], n[1], n[2], -dot(n, v[0]));
SGVec3d isectpoint;
-
- if (fgdRayTriangle(isectpoint, mLocalCacheReference, mLocalDown, v)) {
+ if (intersects(isectpoint, triangle, ray, 1e-4)) {
mGroundCache->found_ground = true;
isectpoint.osg() = isectpoint.osg()*mLocalToGlobal;
- isectpoint += mGroundCache->cache_center;
double this_radius = length(isectpoint);
if (mGroundCache->ground_radius < this_radius) {
mGroundCache->ground_radius = this_radius;
wire.ends[1] = gv2;
wire.velocity = mGroundProperty.vel;
wire.rotation = mGroundProperty.rot;
- wire.rotation_pivot = mGroundProperty.pivot - mGroundCache->cache_center;
+ wire.rotation_pivot = mGroundProperty.pivot;
wire.wire_id = mGroundProperty.wire_id;
mGroundCache->wires.push_back(wire);
}
cat.velocity = mGroundProperty.vel;
cat.rotation = mGroundProperty.rot;
- cat.rotation_pivot = mGroundProperty.pivot - mGroundCache->cache_center;
+ cat.rotation_pivot = mGroundProperty.pivot;
mGroundCache->catapults.push_back(cat);
}
FGGroundCache::FGGroundCache()
{
- cache_center = SGVec3d(0, 0, 0);
ground_radius = 0.0;
cache_ref_time = 0.0;
wire_id = 0;
inline void
FGGroundCache::velocityTransformTriangle(double dt,
- FGGroundCache::Triangle& dst,
+ SGTriangled& dst, SGSphered& sdst,
const FGGroundCache::Triangle& src)
{
- dst = src;
+ dst = src.triangle;
+ sdst = src.sphere;
- if (fabs(dt*dot(src.velocity, src.velocity)) < SGLimitsd::epsilon())
+ if (dt*dt*dot(src.velocity, src.velocity) < SGLimitsd::epsilon())
return;
- for (int i = 0; i < 3; ++i) {
- SGVec3d pivotoff = src.vertices[i] - src.rotation_pivot;
- dst.vertices[i] += dt*(src.velocity + cross(src.rotation, pivotoff));
- }
-
- // Transform the plane equation
- SGVec3d pivotoff, vel;
- sgdSubVec3(pivotoff.sg(), dst.plane.sg(), src.rotation_pivot.sg());
- vel = src.velocity + cross(src.rotation, pivotoff);
- dst.plane[3] += dt*sgdScalarProductVec3(dst.plane.sg(), vel.sg());
-
- dst.boundCenter += dt*src.velocity;
+ SGVec3d baseVert = dst.getBaseVertex();
+ SGVec3d pivotoff = baseVert - src.rotation_pivot;
+ baseVert += dt*(src.velocity + cross(src.rotation, pivotoff));
+ dst.setBaseVertex(baseVert);
+ dst.setEdge(0, dst.getEdge(0) + dt*cross(src.rotation, dst.getEdge(0)));
+ dst.setEdge(1, dst.getEdge(1) + dt*cross(src.rotation, dst.getEdge(1)));
}
+
bool
FGGroundCache::prepare_ground_cache(double ref_time, const SGVec3d& pt,
double rad)
SGQuatd hlToEc = SGQuatd::fromLonLat(SGGeod::fromCart(pt));
down = hlToEc.rotate(SGVec3d(0, 0, 1));
- // Decide where we put the scenery center.
- SGVec3d old_cntr = globals->get_scenery()->get_center();
- SGVec3d cntr(pt);
- // Only move the cache center if it is unacceptable far away.
- if (40*40 < distSqr(old_cntr, cntr))
- globals->get_scenery()->set_center(cntr);
- else
- cntr = old_cntr;
-
- // The center of the cache.
- cache_center = cntr;
-
// Prepare sphere around the aircraft.
- SGVec3d ptoff = pt - cache_center;
double cacheRadius = rad;
// Prepare bigger sphere around the aircraft.
double wireCacheRadius = max_wire_dist < rad ? rad : max_wire_dist;
// Walk the scene graph and extract solid ground triangles and carrier data.
- GroundCacheFillVisitor gcfv(this, down, ptoff, cacheRadius, wireCacheRadius);
+ GroundCacheFillVisitor gcfv(this, down, pt, cacheRadius, wireCacheRadius);
+ gcfv.setSceneryCenter(globals->get_scenery()->get_center());
globals->get_scenery()->get_scene_graph()->accept(gcfv);
// some stats
SG_LOG(SG_FLIGHT, SG_WARN, "prepare_ground_cache(): trying to build cache "
"without any scenery below the aircraft" );
- if (cntr != old_cntr)
- globals->get_scenery()->set_center(old_cntr);
-
return found_ground;
}
rvel[1] = catapults[i].velocity + cross(catapults[i].rotation, pivotoff);
SGVec3d thisEnd[2];
- thisEnd[0] = cache_center + catapults[i].start + t*rvel[0];
- thisEnd[1] = cache_center + catapults[i].end + t*rvel[1];
-
- sgdLineSegment3 ls;
- sgdCopyVec3(ls.a, thisEnd[0].sg());
- sgdCopyVec3(ls.b, thisEnd[1].sg());
- double this_dist = sgdDistSquaredToLineSegmentVec3( ls, dpt.sg() );
+ thisEnd[0] = catapults[i].start + t*rvel[0];
+ thisEnd[1] = catapults[i].end + t*rvel[1];
+ double this_dist = distSqr(SGLineSegmentd(thisEnd[0], thisEnd[1]), dpt);
if (this_dist < dist) {
SG_LOG(SG_FLIGHT,SG_INFO, "Found catapult "
<< this_dist << " meters away");
t -= cache_ref_time;
// The double valued point we start to search for intersection.
- SGVec3d pt = dpt - cache_center;
+ SGVec3d pt = dpt;
// shift the start of our ray by maxaltoff upwards
- SGVec3d raystart = pt - max_altoff*down;
+ SGRayd ray(pt - max_altoff*down, down);
// Initialize to something sensible
double current_radius = 0.0;
size_t sz = triangles.size();
for (size_t i = 0; i < sz; ++i) {
- Triangle triangle;
- velocityTransformTriangle(t, triangle, triangles[i]);
- if (!fgdIsectSphereInfLine(triangle.boundCenter, triangle.boundRadius, pt, down))
+ SGSphered sphere;
+ SGTriangled triangle;
+ velocityTransformTriangle(t, triangle, sphere, triangles[i]);
+ if (!intersectsInf(ray, sphere))
continue;
// Check for intersection.
SGVec3d isecpoint;
- if (fgdRayTriangle(isecpoint, raystart, down, triangle.vertices)) {
+ if (intersects(isecpoint, triangle, ray, 1e-4)) {
// Compute the vector from pt to the intersection point ...
SGVec3d off = isecpoint - pt;
// ... and check if it is too high or not
- // Transform to the wgs system
- isecpoint += cache_center;
+
// compute the radius, good enough approximation to take the geocentric radius
double radius = dot(isecpoint, isecpoint);
if (current_radius < radius) {
// Save the new potential intersection point.
contact = isecpoint;
// The first three values in the vector are the plane normal.
- sgdCopyVec3( normal.sg(), triangle.plane.sg() );
+ normal = triangle.getNormal();
// The velocity wrt earth.
- SGVec3d pivotoff = pt - triangle.rotation_pivot;
- vel = triangle.velocity + cross(triangle.rotation, pivotoff);
+ SGVec3d pivotoff = pt - triangles[i].rotation_pivot;
+ vel = triangles[i].velocity + cross(triangles[i].rotation, pivotoff);
// Save the ground type.
- *type = triangle.type;
+ *type = triangles[i].type;
*agl = dot(down, contact - dpt);
if (material)
- *material = triangle.material;
+ *material = triangles[i].material;
}
}
}
// Build the two triangles spanning the area where the hook has moved
// during the past step.
- SGVec4d plane[2];
- SGVec3d tri[2][3];
- sgdMakePlane( plane[0].sg(), pt[0].sg(), pt[1].sg(), pt[2].sg() );
- tri[0][0] = pt[0];
- tri[0][1] = pt[1];
- tri[0][2] = pt[2];
- sgdMakePlane( plane[1].sg(), pt[0].sg(), pt[2].sg(), pt[3].sg() );
- tri[1][0] = pt[0];
- tri[1][1] = pt[2];
- tri[1][2] = pt[3];
+ SGTriangled triangle[2];
+ triangle[0].set(pt[0], pt[1], pt[2]);
+ triangle[1].set(pt[0], pt[2], pt[3]);
// Intersect the wire lines with each of these triangles.
// You have caught a wire if they intersect.
le[k] = wires[i].ends[k];
SGVec3d pivotoff = le[k] - wires[i].rotation_pivot;
SGVec3d vel = wires[i].velocity + cross(wires[i].rotation, pivotoff);
- le[k] += t*vel + cache_center;
+ le[k] += t*vel;
}
+ SGLineSegmentd lineSegment(le[0], le[1]);
for (int k=0; k<2; ++k) {
- SGVec3d isecpoint;
- double isecval = sgdIsectLinesegPlane(isecpoint.sg(), le[0].sg(),
- le[1].sg(), plane[k].sg());
- if ( 0.0 <= isecval && isecval <= 1.0 &&
- fgdPointInTriangle( isecpoint, tri[k] ) ) {
+ if (intersects(triangle[k], lineSegment)) {
SG_LOG(SG_FLIGHT,SG_INFO, "Caught wire");
// Store the wire id.
wire_id = wires[i].wire_id;
for (size_t k = 0; k < 2; ++k) {
SGVec3d pivotoff = end[k] - wires[i].rotation_pivot;
vel[k] = wires[i].velocity + cross(wires[i].rotation, pivotoff);
- end[k] = cache_center + wires[i].ends[k] + t*vel[k];
+ end[k] = wires[i].ends[k] + t*vel[k];
}
return true;
}