Cálculo de deslocamento e velocidade angular

stock Float:GetXYInFrontOfPlayer(playerid, &Float:x, &Float:y, Float:distance)
{
    static Float:a;
    GetPlayerPos(playerid, x, y, a);

    if(IsPlayerInAnyVehicle(playerid))
        GetVehicleZAngle(GetPlayerVehicleID(playerid), a);
    else
        GetPlayerFacingAngle(playerid, a);

    x += (distance * floatsin(-a, degrees));
    y += (distance * floatcos(-a, degrees));
    return a;
}

stock BoostPlayer(playerid, Float:speed, bool:use_z = false)
{
    static
        Float:X, Float:Y, Float:Z,
        Float:x, Float:y, Float:z;

    GetPlayerPos(playerid, x, y, z);
    GetPlayerPos(playerid, X, Y, Z);
    GetXYInFrontOfPlayer(playerid, X, Y, speed);

    x = ((X < x) ? (x - X) : (X - x));
    y = ((Y < y) ? (y - Y) : (Y - y));

    if(use_z)
        z = ((Z < z) ? (z - Z) : (Z - z));
    else
        z = 0.0;

    return SetPlayerVelocity(playerid, x, y, z);
}