// check for collision course with frame body
// tandir is normal vector from planet to target pos or dir
static bool CheckSuicide(Ship *ship, const vector3d &tandir)
{
Body *body = ship->GetFrame()->GetBodyFor();
if (!body || !body->IsType(Object::TERRAINBODY)) return false;
double vel = ship->GetVelocity().Dot(tandir); // vel towards is negative
double dist = ship->GetPosition().Length() - MaxFeatureRad(body);
if (vel < -1.0 && vel*vel > 2.0*ship->GetAccelMin()*dist)
return true;
return false;
}
// check whether ship is at risk of colliding with frame body on current path
// return values:
//0 - no collision
//1 - below feature height
//2 - unsafe escape from effect radius
//3 - unsafe entry to effect radius
//4 - probable path intercept
static int CheckCollision(Ship *ship, const vector3d &pathdir, double pathdist, const vector3d &tpos, double endvel, double r)
{
// ship is in obstructor's frame anyway, so is tpos
if (pathdist < 100.0) return 0;
Body *body = ship->GetFrame()->GetBodyFor();
if (!body) return 0;
vector3d spos = ship->GetPosition();
double tlen = tpos.Length(), slen = spos.Length();
double fr = MaxFeatureRad(body);
// if target inside, check if direct entry is safe (30 degree)
if (tlen < r) {
double af = (tlen > fr) ? 0.5 * (1 - (tlen-fr) / (r-fr)) : 0.5;
if (pathdir.Dot(tpos) > -af*tlen)
if (slen < fr) return 1; else return 3;
else return 0;
}
// if ship inside, check for max feature height and direct escape (30 degree)
if (slen < r) {
if (slen < fr) return 1;
double af = (slen > fr) ? 0.5 * (1 - (slen-fr) / (r-fr)) : 0.5;
if (pathdir.Dot(spos) < af*slen) return 2; else return 0;
}
// now for the intercept calc
// find closest point to obstructor
double tanlen = -spos.Dot(pathdir);
if (tanlen < 0 || tanlen > pathdist) return 0; // closest point outside path
vector3d perpdir = (tanlen*pathdir + spos).Normalized();
double perpspeed = ship->GetVelocity().Dot(perpdir);
double parspeed = ship->GetVelocity().Dot(pathdir);
if (parspeed < 0) parspeed = 0; // shouldn't break any important case
if (perpspeed > 0) perpspeed = 0; // prevent attempts to speculatively fly through planets
// find time that ship will pass through that point
// get velocity as if accelerating from start or end, pick smallest
double ivelsqr = endvel*endvel + 2*ship->GetAccelFwd()*(pathdist-tanlen); // could put endvel in here
double fvelsqr = parspeed*parspeed + 2*ship->GetAccelFwd()*tanlen;
double tanspeed = sqrt(ivelsqr < fvelsqr ? ivelsqr : fvelsqr);
double time = tanlen / (0.5 * (parspeed + tanspeed)); // actually correct?
double dist = spos.Dot(perpdir) + perpspeed*time; // spos.perpdir should be positive
if (dist < r) return 4;
return 0;
}
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;
}
bool AICmdFlyTo::TimeStepUpdate()
{
double timestep = Pi::game->GetTimeStep();
vector3d targvel = GetVelInFrame(m_ship->GetFrame(), m_targframe, m_posoff);
vector3d relvel = m_ship->GetVelocity() - targvel;
vector3d targpos = GetPosInFrame(m_ship->GetFrame(), m_targframe, m_posoff);
bool safe = ParentSafetyAdjust(m_ship, m_targframe, m_posoff, targpos);
double endvel = safe ? 0.0 : m_endvel; // don't use endvel if safety-adjusted
vector3d relpos = targpos - m_ship->GetPosition();
vector3d reldir = relpos.NormalizedSafe();
double targdist = relpos.Length();
// sort out gear, launching
if (m_ship->GetFlightState() == Ship::FLYING) m_ship->SetWheelState(false);
else { LaunchShip(m_ship); return false; }
// frame switch stuff - clear children/collision state
if (m_frame != m_ship->GetFrame()) {
if (m_child) { delete m_child; m_child = 0; }
if (m_frame && m_tangent) return true; // regen tangent on frame switch
m_frame = m_ship->GetFrame();
m_reldir = reldir; // for +vel termination condition
}
#ifdef DEBUG_AUTOPILOT
if (m_ship->IsType(Object::PLAYER))
printf("Autopilot dist = %.1f, speed = %.1f, zthrust = %.2f, term = %.3f, state = %i\n",
targdist, relvel.Length(), m_ship->GetThrusterState().z, reldir.Dot(m_reldir), m_state);
#endif
Body *body = m_frame->GetBodyFor();
double erad = MaxEffectRad(body, m_ship);
if (!m_tangent || !(body == m_targframe->GetBodyFor()))
{
// process path collisions with frame body
int coll = CheckCollision(m_ship, reldir, targdist, targpos, endvel, erad);
if (coll == 0) { // no collision
if (m_child) { delete m_child; m_child = 0; m_state = -1; }
}
else if (coll == 1) { // below feature height, target not below
double ang = m_ship->AIFaceDirection(m_ship->GetPosition());
m_ship->AIMatchVel(ang < 0.05 ? 1000.0 * m_ship->GetPosition().Normalized() : 0.0);
m_state = -3; return false;
}
else { // same thing for 2/3/4
if (!m_child) m_child =
new AICmdFlyAround(m_ship, body, erad, 0.0, m_targframe, m_posoff);
ProcessChild(); m_state = -5; return false;
}
}
// if dangerously close to local body, pretend target isn't moving
if (body) {
double localdist = m_ship->GetPosition().Length();
if (targdist > localdist && localdist < 1.5*MaxFeatureRad(body))
relvel += targvel;
}
// regenerate state to flipmode if we're off course
bool overshoot = CheckOvershoot(m_ship, reldir, targdist, relvel, endvel);
if (m_tangent && m_state == -4 && !overshoot) return true; // bail out
if (m_state < 0) m_state = GetFlipMode(m_ship, relpos, relvel);
// linear thrust
double ang, maxdecel = GetMaxDecel(m_ship, reldir, m_state, &ang);
maxdecel -= GetGravityAtPos(m_targframe, m_posoff);
if(maxdecel <= 0) { m_ship->AIMessage(Ship::AIERROR_GRAV_TOO_HIGH); return true; }
bool cap = m_ship->AIMatchPosVel2(reldir, targdist, relvel, endvel, maxdecel);
// path overshoot check, response
if (m_state < 3 && overshoot) {
double ispeed = calc_ivel(targdist, endvel, maxdecel);
m_ship->AIFaceDirection(ispeed*reldir - relvel);
m_state = -4; return false;
}
// flip check - if facing forward and not accelerating at maximum
if (m_state == 1 && ang > 0.99 && !cap) m_state = 2;
// termination conditions
if (m_state == 3) m_state++; // finished last adjustment, hopefully
else if (endvel > 0.0) { if (reldir.Dot(m_reldir) < 0.9) m_state = 4; }
else if (targdist < 0.5*m_ship->GetAccelMin()*timestep*timestep) m_state = 3;
// set heading according to current state
if (m_state < 2) { // this shit still needed? yeah, sort of
vector3d newrelpos = targpos - m_ship->AIGetNextFramePos();
if ((newrelpos + reldir*100.0).Dot(relpos) <= 0.0)
m_ship->AIFaceDirection(reldir); // last frames turning workaround
else m_ship->AIFaceDirection(newrelpos);
}
else if (m_state == 2) m_ship->AIFaceDirection(-reldir); // hmm. -relvel instead?
else m_ship->AIMatchAngVelObjSpace(vector3d(0.0));
if (m_state == 4) return true;
return false;
}
bool AICmdFlyTo::TimeStepUpdate()
{
double timestep = Pi::game->GetTimeStep();
vector3d targvel = GetVelInFrame(m_ship->GetFrame(), m_targframe, m_posoff);
vector3d relvel = m_ship->GetVelocity() - targvel;
vector3d targpos = GetPosInFrame(m_ship->GetFrame(), m_targframe, m_posoff);
// only if pursuing a ship -- repeat actions from contructor again, since the position of the ship changed
if(m_targetShip != 0) {
m_targframe = m_targetShip->GetFrame();
m_posoff = m_ship->GetPositionRelTo(m_targframe);
m_posoff += m_targetShip->GetPosition();
targpos = m_targetShip->GetPositionRelTo(m_ship->GetFrame());
targpos.x += VICINITY_MIN/2; // avoid collisions, set target a bit away
targvel = m_targetShip->GetVelocityRelTo(m_ship->GetFrame()); // todo: check general frame!
relvel = m_ship->GetVelocity() - targvel;
}
bool safe = ParentSafetyAdjust(m_ship, m_targframe, m_posoff, targpos);
double endvel = safe ? 0.0 : m_endvel; // don't use endvel if safety-adjusted
vector3d relpos = targpos - m_ship->GetPosition();
vector3d reldir = relpos.NormalizedSafe();
double targdist = relpos.Length();
double haveFuelToReachThisVelSafely;
m_fuelEconomy = Clamp(m_fuelEconomy, 0.0f, 1.0f);
haveFuelToReachThisVelSafely = m_ship->GetVelocityReachedWithFuelUsed(1.0/(6-3*m_fuelEconomy) * m_ship->GetFuel());
// sort out gear, launching
if (m_ship->GetFlightState() == Ship::FLYING) m_ship->SetWheelState(false);
else { LaunchShip(m_ship); return false; }
// frame switch stuff - clear children/collision state
if (m_frame != m_ship->GetFrame()) {
if (m_child) { delete m_child; m_child = 0; }
if (m_frame && m_tangent) return true; // regen tangent on frame switch
m_frame = m_ship->GetFrame();
m_reldir = reldir; // for +vel termination condition
}
#ifdef DEBUG_AUTOPILOT
if (m_ship->IsType(Object::PLAYER))
printf("Autopilot dist = %.1f, speed = %.1f, zthrust = %.2f, term = %.3f, crit = %.3f, fuel = %.3f, exhaust = %.0f, safeVel = %.0f, state = %i\n",
targdist, relvel.Length(), m_ship->GetThrusterState().z, reldir.Dot(m_reldir),
relvel.Dot(reldir)/(relvel.Length()+1e-7), m_ship->GetFuel(),
m_ship->GetEffectiveExhaustVelocity() , haveFuelToReachThisVelSafely, m_state);
#endif
Body *body = m_frame->GetBodyFor();
double erad = MaxEffectRad(body, m_ship);
if (m_targetShip == 0 && (!m_tangent || !(body == m_targframe->GetBodyFor())))
{
// process path collisions with frame body
int coll = CheckCollision(m_ship, reldir, targdist, targpos, endvel, erad);
if (coll == 0) { // no collision
if (m_child) { delete m_child; m_child = 0; m_state = -1; }
}
else if (coll == 1) { // below feature height, target not below
double ang = m_ship->AIFaceDirection(m_ship->GetPosition());
m_ship->AIMatchVel(ang < 0.05 ? 1000.0 * m_ship->GetPosition().Normalized() : vector3d(0.0));
m_state = -3; return false;
}
else { // same thing for 2/3/4
if (!m_child) m_child =
new AICmdFlyAround(m_ship, body, erad, 0.0, m_targframe, m_posoff, m_fuelEconomy);
ProcessChild(); m_state = -5; return false;
}
}
// if dangerously close to local body, pretend target isn't moving
if (body) {
double localdist = m_ship->GetPosition().Length();
if (targdist > localdist && localdist < 1.5*MaxFeatureRad(body))
relvel += targvel;
}
// regenerate state to flipmode if we're off course
bool overshoot = CheckOvershoot(m_ship, reldir, targdist, relvel, endvel);
if (m_tangent && m_state == -4 && !overshoot) return true; // bail out
if (m_state < 0) m_state = GetFlipMode(m_ship, relpos, relvel);
// linear thrust
double ang, maxdecel = GetMaxDecel(m_ship, reldir, m_state, &ang);
maxdecel -= GetGravityAtPos(m_targframe, m_posoff);
if(maxdecel <= 0) { m_ship->AIMessage(Ship::AIERROR_GRAV_TOO_HIGH); return true; }
bool cap = m_ship->AIMatchPosVel2(reldir, targdist, relvel, endvel, maxdecel);
// path overshoot check, response
if (m_state < 3 && overshoot) {
double ispeed = calc_ivel(targdist, endvel, maxdecel);
m_ship->AIFaceDirection(ispeed*reldir - relvel);
m_state = -4; return false;
}
// turn thrusters off when in acceleration phase and low on fuel
double angleCos = relvel.Dot(reldir)/(relvel.Length()+1e-7);
if(m_state == 1 && relvel.Length() > haveFuelToReachThisVelSafely &&
// match direction precisely if close, if more than a day far, save the fuel and do not be so strict about the direction
(angleCos > 0.9999 || (angleCos > 0.995 && targdist/(haveFuelToReachThisVelSafely+1e-7) > 86400))
) {
m_ship->SetThrusterState(vector3d(0.0));
} else if(m_state == 1 && relvel.Length() > 1.1*haveFuelToReachThisVelSafely) {
// match direction without increasing speed .. saves fuel in deceleration phase
vector3d v;
matrix4x4d m;
m_ship->GetRotMatrix(m);
v = targvel + relvel.NormalizedSafe()*haveFuelToReachThisVelSafely;
m_ship->AIMatchVel(v);
}
// flip check - if facing forward and not accelerating at maximum
if (m_state == 1 && ang > 0.99 && !cap) m_state = 2;
// termination conditions
if (m_state == 3) m_state++; // finished last adjustment, hopefully
else if (endvel > 0.0) { if (reldir.Dot(m_reldir) < 0.9) m_state = 4; }
else if (targdist < 0.5*m_ship->GetAccelMin()*timestep*timestep) m_state = 3;
// set heading according to current state
if (m_state < 2) { // this shit still needed? yeah, sort of
vector3d newrelpos = targpos - m_ship->AIGetNextFramePos();
if ((newrelpos + reldir*100.0).Dot(relpos) <= 0.0)
m_ship->AIFaceDirection(reldir); // last frames turning workaround
else m_ship->AIFaceDirection(newrelpos);
}
else if (m_state == 2) m_ship->AIFaceDirection(-reldir); // hmm. -relvel instead?
else m_ship->AIMatchAngVelObjSpace(vector3d(0.0));
if (m_state == 4) return true;
return false;
}
