// diffvel is required change in velocity in object space
// returns true if this can be done in a single timestep
bool Ship::AIChangeVelBy(const vector3d &diffvel)
{
// counter external forces
vector3d extf = GetExternalForce() * (Pi::game->GetTimeStep() / GetMass());
vector3d diffvel2 = diffvel - extf * GetOrient();
vector3d maxThrust = GetMaxThrust(diffvel2);
vector3d maxFrameAccel = maxThrust * (Pi::game->GetTimeStep() / GetMass());
vector3d thrust(diffvel2.x / maxFrameAccel.x,
diffvel2.y / maxFrameAccel.y,
diffvel2.z / maxFrameAccel.z);
SetThrusterState(thrust); // use clamping
if (thrust.x*thrust.x > 1.0 || thrust.y*thrust.y > 1.0 || thrust.z*thrust.z > 1.0) return false;
return true;
}
// Change object-space velocity in direction of param
vector3d Ship::AIChangeVelDir(const vector3d &reqdiffvel)
{
// get max thrust in desired direction after external force compensation
vector3d maxthrust = GetMaxThrust(reqdiffvel);
maxthrust += GetExternalForce() * GetOrient();
vector3d maxFA = maxthrust * (Pi::game->GetTimeStep() / GetMass());
maxFA.x = fabs(maxFA.x); maxFA.y = fabs(maxFA.y); maxFA.z = fabs(maxFA.z);
// crunch diffvel by relative thruster power to get acceleration in right direction
vector3d diffvel = reqdiffvel;
if (fabs(diffvel.x) > maxFA.x) diffvel *= maxFA.x / fabs(diffvel.x);
if (fabs(diffvel.y) > maxFA.y) diffvel *= maxFA.y / fabs(diffvel.y);
if (fabs(diffvel.z) > maxFA.z) diffvel *= maxFA.z / fabs(diffvel.z);
AIChangeVelBy(diffvel); // should always return true because it's already capped?
return GetOrient() * (reqdiffvel - diffvel); // should be remaining diffvel to correct
}
// diffvel is required change in velocity in object space
// returns true if this can be done in a single timestep
bool Ship::AIChangeVelBy(const vector3d &diffvel)
{
// counter external forces unless we're in an orbital station rotating frame
matrix4x4d rot; GetRotMatrix(rot);
vector3d diffvel2 = GetExternalForce() * Pi::GetTimeStep() / GetMass();
if (GetFrame()->IsStationRotFrame()) diffvel2 = diffvel;
else diffvel2 = diffvel - diffvel2 * rot;
vector3d maxThrust = GetMaxThrust(diffvel2);
vector3d maxFrameAccel = maxThrust * Pi::GetTimeStep() / GetMass();
vector3d thrust(diffvel2.x / maxFrameAccel.x,
diffvel2.y / maxFrameAccel.y,
diffvel2.z / maxFrameAccel.z);
SetThrusterState(thrust); // use clamping
if (thrust.x*thrust.x > 1.0 || thrust.y*thrust.y > 1.0 || thrust.z*thrust.z > 1.0) return false;
return true;
}
