ptr[2] = vec[2];
}
-// base_fdm_state is the internal state that is updated in integer
-// multiples of "dt". This leads to "jitter" with respect to the real
-// world time, so we introduce cur_fdm_state which is extrapolated by
-// the difference between sim time and real world time
-
FGInterface *cur_fdm_state = 0;
-FGInterface base_fdm_state;
// Constructor
FGInterface::FGInterface()
- : remainder(0)
{
_setup();
}
FGInterface::FGInterface( double dt )
- : remainder(0)
{
_setup();
}
// unbind(); // FIXME: should be called explicitly
}
-
int
FGInterface::_calc_multiloop (double dt)
{
+ // Since some time the simulation time increments we get here are
+ // already a multiple of the basic update freqency.
+ // So, there is no need to do our own multiloop rounding with all bad
+ // roundoff problems when we already have nearly accurate values.
+ // Only the speedup thing must be still handled here
int hz = fgGetInt("/sim/model-hz");
+ int multiloop = SGMiscd::roundToInt(dt*hz);
int speedup = fgGetInt("/sim/speed-up");
-
- dt += remainder;
- remainder = 0;
- double ml = dt * hz;
- // Avoid roundoff problems by adding the roundoff itself.
- // ... ok, two times the roundoff to have enough room.
- int multiloop = int(floor(ml * (1.0 + 2.0*DBL_EPSILON)));
- remainder = (ml - multiloop) / hz;
-
- // If we artificially inflate ml above by a tiny amount to get the
- // closest integer, then subtract the integer from the original
- // slightly smaller value, we can get a negative remainder.
- // Logically this should never happen, and we definitely don't want
- // to carry a negative remainder over to the next iteration, so
- // never let the remainder go below zero.
- //
- // Note: this fixes a problem where we run 1, 3, 1, 3, 1, 3... loops
- // of the FDM when in fact we want to run 2, 2, 2, 2, 2...
- if ( remainder < 0 ) { remainder = 0; }
-
- return (multiloop * speedup);
+ return multiloop * speedup;
}
set_inited( true );
-// stamp();
-// set_remainder( 0 );
+ ground_cache.set_cache_time_offset(globals->get_sim_time_sec());
// Set initial position
SG_LOG( SG_FLIGHT, SG_INFO, "...initializing position..." );
{
bound = true;
- // Time management (read-only)
-// fgTie("/fdm/time/delta_t", this,
-// &FGInterface::get_delta_t); // read-only
-// fgTie("/fdm/time/elapsed", this,
-// &FGInterface::get_elapsed); // read-only
-// fgTie("/fdm/time/remainder", this,
-// &FGInterface::get_remainder); // read-only
-// fgTie("/fdm/time/multi_loop", this,
-// &FGInterface::get_multi_loop); // read-only
-
// Aircraft position
fgTie("/position/latitude-deg", this,
&FGInterface::get_Latitude_deg,
{
bound = false;
- // fgUntie("/fdm/time/delta_t");
- // fgUntie("/fdm/time/elapsed");
- // fgUntie("/fdm/time/remainder");
- // fgUntie("/fdm/time/multi_loop");
fgUntie("/position/latitude-deg");
fgUntie("/position/longitude-deg");
fgUntie("/position/altitude-ft");
// FIXME: how to handle t - ref_time differences ???
SGVec3d cpos;
- double ref_time, radius;
+ double ref_time = 0, radius;
// Prepare the ground cache for that position.
if (!is_valid_m(&ref_time, cpos.data(), &radius)) {
- double startTime = globals->get_sim_time_sec();
+ double startTime = ref_time;
double endTime = startTime + 1;
bool ok = prepare_ground_cache_m(startTime, endTime, pos.data(), 10);
/// This is most likely the case when the given altitude is
return 0;
}
} else if (radius*radius <= distSqr(pos, cpos)) {
- double startTime = globals->get_sim_time_sec();
+ double startTime = ref_time;
double endTime = startTime + 1;
/// We reuse the old radius value, but only if it is at least 10 Meters ..