void MoveSpline::computeParabolicElevation(float& el) const
{
    if (time_passed > effect_start_time)
    {
        float t_passedf = MSToSec(time_passed - effect_start_time);
        float t_durationf = MSToSec(Duration() - effect_start_time); //client use not modified duration here

        // -a*x*x + bx + c:
        //(dur * v3->z_acceleration * dt)/2 - (v3->z_acceleration * dt * dt)/2 + Z;
        el += (t_durationf - t_passedf) * 0.5f * vertical_acceleration * t_passedf;
    }
}

void MoveSpline::Initialize(const MoveSplineInitArgs& args)
{
    splineflags = args.flags;
    facing = args.facing;
    m_Id = args.splineId;
    point_Idx_offset = args.path_Idx_offset;
    initialOrientation = args.initialOrientation;

    onTransport = false;
    time_passed = 0;
    vertical_acceleration = 0.f;
    effect_start_time = 0;

    // Check if its a stop spline
    if (args.flags.done)
    {
        spline.clear();
        return;
    }

    init_spline(args);

    // init parabolic / animation
    // spline initialized, duration known and i able to compute parabolic acceleration
    if (args.flags & (MoveSplineFlag::Parabolic | MoveSplineFlag::Animation))
    {
        effect_start_time = Duration() * args.time_perc;
        if (args.flags.parabolic && effect_start_time < Duration())
        {
            float f_duration = MSToSec(Duration() - effect_start_time);
            vertical_acceleration = args.parabolic_amplitude * 8.f / (f_duration * f_duration);
        }
    }
}

void MoveSpline::Initialize(MoveSplineInitArgs const& args)
{
    splineflags = args.flags;
    facing = args.facing;
    m_Id = args.splineId;
    point_Idx_offset = args.path_Idx_offset;
    initialOrientation = args.initialOrientation;

    time_passed = 0;
    vertical_acceleration = 0.f;
    effect_start_time = 0;
    splineIsFacingOnly = args.path.size() == 2 && args.facing.type != MONSTER_MOVE_NORMAL && ((args.path[1] - args.path[0]).length() < 0.1f);

    // Check if its a stop spline
    if (args.flags.done)
    {
        spline.clear();
        return;
    }

    init_spline(args);

    // init parabolic / animation
    // spline initialized, duration known and i able to compute parabolic acceleration
    if (args.flags & (MoveSplineFlag::Parabolic | MoveSplineFlag::Animation | MoveSplineFlag::Unknown6))
    {
        effect_start_time = Duration() * args.time_perc;
        if (args.flags.parabolic && effect_start_time < Duration())
        {
            float f_duration = MSToSec(Duration() - effect_start_time);
            vertical_acceleration = args.parabolic_amplitude * 8.f / (f_duration * f_duration);
        }
    }
}

void MoveSpline::Initialize(const MoveSplineInitArgs& args)
{
    splineflags = args.flags;
    facing = args.facing;
    m_Id = args.splineId;
    point_Idx_offset = args.path_Idx_offset;
    initialOrientation = args.initialOrientation;
    transportGuid = args.transportGuid;
    transportSeat = args.transportSeat;
    transportPos = args.transportPos;

    time_passed = 0;
    vertical_acceleration = 0.f;
    effect_start_time = 0;

    init_spline(args);

    // init parabolic / animation
    // spline initialized, duration known and i able to compute parabolic acceleration
    if (args.flags & (MoveSplineFlag::Trajectory | MoveSplineFlag::Animation))
    {
        effect_start_time = Duration() * args.time_perc;
        if (args.flags.parabolic && effect_start_time < Duration())
        {
            float f_duration = MSToSec(Duration() - effect_start_time);
            vertical_acceleration = args.parabolic_amplitude * 8.f / (f_duration * f_duration);
        }
    }
}

void MoveSpline::computeFallElevation(float& el) const
{
    float z_now = spline.getPoint(spline.first()).z - Movement::computeFallElevation(MSToSec(time_passed));
    float final_z = FinalDestination().z;
    if (z_now < final_z)
        el = final_z;
    else
        el = z_now;
}

void MoveSpline::computeFallElevation(float& el) const
{
    float z_now = spline.getPoint(spline.first()).z - Movement::computeFallElevation(MSToSec(time_passed), false);
    float final_z = FinalDestination().z;
    el = std::max(z_now, final_z);
}