AirspaceIntersectionVector
AirspaceCircle::intersects(const GeoPoint& start, const GeoVector &vec) const
{
const GeoPoint end = vec.end_point(start);
AirspaceIntersectSort sorter(start, end, *this);
const fixed f_radius = m_task_projection->fproject_range(m_center, m_radius);
const FlatPoint f_center = m_task_projection->fproject(m_center);
const FlatPoint f_start = m_task_projection->fproject(start);
const FlatPoint f_end = m_task_projection->fproject(end);
const FlatLine line(f_start, f_end);
if (inside(start))
sorter.add(fixed_zero, start);
FlatPoint f_p1, f_p2;
if (line.intersect_circle(f_radius, f_center, f_p1, f_p2)) {
const fixed mag = line.mag_sq();
if (positive(mag)) {
fixed inv_mag = -fixed_one;
const fixed t1 = FlatLine(f_start, f_p1).dot(line);
const fixed t2 = (f_p1 == f_p2) ?
-fixed_one : FlatLine(f_start, f_p2).dot(line);
const bool in_range = (t1 < mag) || (t2 < mag);
// if at least one point is within range, capture both points
if ((t1 >= fixed_zero) && in_range) {
if (negative(inv_mag))
inv_mag = fixed_one / mag;
sorter.add(t1 * inv_mag, m_task_projection->funproject(f_p1));
}
if ((t2 >= fixed_zero) && in_range) {
if (negative(inv_mag))
inv_mag = fixed_one / mag;
sorter.add(t2 * inv_mag, m_task_projection->funproject(f_p2));
}
}
}
return sorter.all();
}
void
Airspaces::visit_intersecting(const GeoPoint &loc,
const GeoVector &vec,
AirspaceIntersectionVisitor& visitor) const
{
FlatRay ray(task_projection.project(loc),
task_projection.project(vec.end_point(loc)));
GeoPoint c = vec.mid_point(loc);
Airspace bb_target(c, task_projection);
int mrange = task_projection.project_range(c, vec.Distance / 2);
IntersectingAirspaceVisitorAdapter adapter(loc, vec, ray, visitor);
airspace_tree.visit_within_range(bb_target, -mrange, adapter);
#ifdef INSTRUMENT_TASK
n_queries++;
#endif
}
AirspaceIntersectionVector
AirspacePolygon::intersects(const GeoPoint& start,
const GeoVector &vec) const
{
const GeoPoint end = vec.end_point(start);
const FlatRay ray(m_task_projection->project(start),
m_task_projection->project(end));
AirspaceIntersectSort sorter(start, end, *this);
for (SearchPointVector::const_iterator it= m_border.begin();
it+1 != m_border.end(); ++it) {
const FlatRay r_seg(it->get_flatLocation(),
(it+1)->get_flatLocation());
const fixed t = ray.intersects(r_seg);
if (t>=fixed_zero) {
sorter.add(t, m_task_projection->unproject(ray.parametric(t)));
}
}
return sorter.all();
}
