IsPlayerWheelie

stock GetVehicleRotation(vehicleid, &Float:x, &Float:y, &Float:z)
{
    new Float:quat_w, Float:quat_x, Float:quat_y, Float:quat_z;
    GetVehicleRotationQuat(vehicleid, quat_w, quat_x, quat_y, quat_z);
    x = atan2(2*((quat_x*quat_y)+(quat_w+quat_z)), (quat_w*quat_w)+(quat_x*quat_x)-(quat_y*quat_y)-(quat_z*quat_z));
    y = atan2(2*((quat_y*quat_z)+(quat_w*quat_x)), (quat_w*quat_w)-(quat_x*quat_x)-(quat_y*quat_y)+(quat_z*quat_z));
    z = asin(-2*((quat_x*quat_z)+(quat_w*quat_y)));
}

stock IsVehicleWheelie(vehicleid)
{
    new Float:rot[3];
    GetVehicleRotation(vehicleid, rot[0], rot[1], rot[2]);
    if((rot[1] >= 30.0 && rot[1] < 90.0) || (rot[1] <= -30.0 && rot[1] > -90.0)) return 1;
    return 0;
}

stock IsPlayerWheelie(playerid)
{
    if(!IsPlayerInAnyVehicle(playerid)) return 0;
    return IsVehicleWheelie(GetPlayerVehicleID(playerid));
}