void AICmdFlyAround::Setup(Body *obstructor, double alt, double vel, int targmode, Body *target, Frame *targframe, const vector3d &posoff)
{
m_obstructor = obstructor; m_alt = alt; m_vel = vel;
m_targmode = targmode; m_target = target; m_targframe = targframe; m_posoff = posoff;
// generate suitable velocity if none provided
double minacc = (targmode == 3) ? 0 : m_ship->GetAccelMin();
double mass = obstructor->IsType(Object::TERRAINBODY) ? obstructor->GetMass() : 0;
if (vel < 1e-30) m_vel = sqrt(m_alt*0.8*minacc + mass*G/m_alt);
// check if altitude is within obstructor frame
if (alt > 0.9 * GetNonRotFrame(obstructor)->GetRadius()) {
m_ship->AIMessage(Ship::AIERROR_ORBIT_IMPOSSIBLE);
m_targmode = 1; m_target = 0; // force an exit
}
}
// Pursue ship, not body
AICmdFlyTo::AICmdFlyTo(Ship *ship, Ship *target, float hungriness) : AICommand (ship, CMD_FLYTO)
{
double dist = std::max(VICINITY_MIN, VICINITY_MUL*MaxEffectRad(target, ship));
m_targframe = GetNonRotFrame(target);
m_posoff = dist * m_ship->GetPositionRelTo(m_targframe).Normalized();
m_posoff += target->GetPosition();
m_endvel = 0; m_tangent = 0;
m_state = -1; m_frame = 0;
// check if we're already close enough
if (dist > m_ship->GetPositionRelTo(target).Length()) m_state = 5;
m_fuelEconomy = Clamp(hungriness, 0.0f, 1.0f);;
m_targetShip = target;
}
// Fly to "vicinity" of body
AICmdFlyTo::AICmdFlyTo(Ship *ship, Body *target) : AICommand (ship, CMD_FLYTO)
{
double dist = std::max(VICINITY_MIN, VICINITY_MUL*MaxEffectRad(target, ship));
if (target->IsType(Object::SPACESTATION) && static_cast<SpaceStation *>(target)->IsGroundStation()) {
matrix4x4d rot; target->GetRotMatrix(rot);
m_posoff = target->GetPosition() + dist * vector3d(rot[4], rot[5], rot[6]); // up vector for starport
m_targframe = target->GetFrame();
}
else {
m_targframe = GetNonRotFrame(target);
m_posoff = dist * m_ship->GetPositionRelTo(m_targframe).Normalized();
m_posoff += target->GetPosition();
}
m_endvel = 0; m_tangent = 0;
m_state = -1; m_frame = 0;
// check if we're already close enough
if (dist > m_ship->GetPositionRelTo(target).Length()) m_state = 5;
}
bool AICmdFlyAround::TimeStepUpdate()
{
if (m_targmode == 1 && !m_target) return true;
if (!ProcessChild()) return false;
// Not necessary unless it's a tier 1 AI
if (m_ship->GetFlightState() == Ship::FLYING) m_ship->SetWheelState(false);
else { LaunchShip(m_ship); return false; }
double timestep = Pi::game->GetTimeStep();
vector3d targpos = Targpos(); // target position in ship's frame
vector3d obspos = m_obstructor->GetPositionRelTo(m_ship);
double obsdist = obspos.Length();
vector3d obsdir = obspos / obsdist;
vector3d relpos = targpos - m_ship->GetPosition();
// if too far away, fly to tangent
if (obsdist > 1.1*m_alt)
{
double v;
Frame *obsframe = GetNonRotFrame(m_obstructor);
vector3d tangent = GenerateTangent(m_ship, obsframe, targpos, m_alt);
vector3d tpos_obs = GetPosInFrame(obsframe, m_ship->GetFrame(), targpos);
if (m_targmode != 1 && m_targmode != 2) v = m_vel;
else if (relpos.LengthSqr() < obsdist) v = 0.0;
else v = MaxVel((tpos_obs-tangent).Length(), tpos_obs.Length());
m_child = new AICmdFlyTo(m_ship, obsframe, tangent, v, true);
ProcessChild(); return false;
}
// limit m_vel by target proximity & distance covered per frame
double vel = (m_targmode != 1 && m_targmode != 2) ? m_vel
: MaxVel(relpos.Length(), targpos.Length());
// all calculations in ship's frame
vector3d fwddir = (obsdir.Cross(relpos).Cross(obsdir)).Normalized();
vector3d tanvel = vel * fwddir;
// frame body suicide check, response
if (CheckSuicide(m_ship, -obsdir)) {
m_ship->AIFaceDirection(m_ship->GetPosition()); // face away from planet
m_ship->AIMatchVel(vector3d(0.0)); return false;
}
// max feature avoidance check, response
if (obsdist < MaxFeatureRad(m_obstructor)) {
double ang = m_ship->AIFaceDirection(-obsdir);
m_ship->AIMatchVel(ang < 0.05 ? 1000.0 * -obsdir : 0.0);
return false;
}
// calculate target velocity
double alt = (tanvel * timestep + obspos).Length(); // unnecessary?
double ivel = calc_ivel(alt - m_alt, 0.0, m_ship->GetAccelMin());
vector3d finalvel = tanvel + ivel * obsdir;
m_ship->AIMatchVel(finalvel);
m_ship->AIFaceDirection(fwddir);
// vector3d newhead = GenerateTangent(m_ship, m_obstructor->GetFrame(), fwddir);
// newhead = GetPosInFrame(m_ship->GetFrame(), m_obstructor->GetFrame(), newhead);
// m_ship->AIFaceDirection(newhead-m_ship->GetPosition());
// termination condition for orbits
vector3d thrust = m_ship->GetThrusterState();
if (m_targmode >= 3 && thrust.LengthSqr() < 0.01) m_targmode++;
if (m_targmode == 5) { m_ship->SetThrusterState(vector3d(0.0)); return true; }
return false;
}
