Hello 3DRad community,

I am doing a project (originally using AircrafDemo_autobalance.3dr project)that makes a UAV flies automatically from point A to point B..Where it will:

Take off automatically
Check the locations  of the Target (x1,y1,z1) and the UAV (x2,y2,z2) via iOjectLocation
void Position_target ()
{
   iObjectLocation(OBJ_458,Ball);
}   

void Position_plane ()
{
   Vector3 Location_propeller;
   Vector3 Location_elevator;
   Vector3 Location_rudder;
   Vector3 Location_rightaileron;
   Vector3 Location_leftaileron;

   iObjectLocation(OBJ_0,Location_propeller);
   iObjectLocation(OBJ_18,Location_elevator);
   iObjectLocation(OBJ_40,Location_rudder);
   iObjectLocation(OBJ_62,Location_rightaileron);
   iObjectLocation(OBJ_84,Location_leftaileron);

   
   Location.x = (Location_propeller.x + Location_elevator.x + Location_rudder.x + Location_rightaileron.x + Location_leftaileron.x)/5;
   Location.y = (Location_propeller.y + Location_elevator.y + Location_rudder.y + Location_rightaileron.y + Location_leftaileron.y)/5;
   Location.z = (Location_propeller.z + Location_elevator.z + Location_rudder.z + Location_rightaileron.z + Location_leftaileron.z)/5;
}Get the length of the 2 vectors (from the origin ) using iVectorLength () or float = iFloatSqrt(x*x+y*y+z*z)
void length ()
{
   lengthUAV = iFloatSqrt(Location.x*Location.x + Location.y*Location.y + Location.z*Location.z);
   
   //lengthUAV = iVectorLength(Location);
   
   lengthTarget = iFloatSqrt(Ball.x*Ball.x + Ball.y*Ball.y + Ball.z*Ball.z);
   //lengthTarget = iVectorLength(Ball);
}Get the dot product between them using iVectorDot() or float = x1*x2+y1*y2+z1*z2
Get the theta in cos(theta) where theta = dotproduct/(lengthUAV*lengthTarget)
oid dot_product ()
{
   //[UAVx UAVy UAVz].[Targetx Targety Targetz]

   //dotproduct = Location.x*Ball.x + Location.y*Ball.y + Location.z*Ball.z;

  // iVectorLengthSet(nLocation,Location,1);
  // iVectorLengthSet(nBall,Ball,1);
   

   dotproduct = iVectorDot(Location,Ball);

   dot = dotproduct/(lengthUAV*lengthTarget);
   
   arc_cos (dot);

   
}Get theta via a_cos(theta) by using MathRad.dll
float arc_cos (float value)
{
   iDLLArraySet(0,value);
   iDLLCall(MathDLLHandle,"R_acos",0);
   angle = iDLLArrayGet(0);
   return angle;
}
Now the problem is I am getting a very big angle and the UAV is turning accordingly to the other side of the map, beyond the target.
I checked into it and found that the dot product (which is suppose to be from -1 to 1) is very huge no matter what option I choose (iVectorDot or the formula) which led me to this question:

what does iObjectLocation(OBJ_X,Vector3) really gives

PN: thanks to all who helped me in the previous post, also I am new to the 3DRad community, if I posted in the wrong thread, please kindly advice me

Regards,
Forat