How to determine the direction of an object to the player.

[SwirlyBitz]

I have a 3rd person game. The thing i want to do is if the object is on my left and right. The rigidbody Constraints lock the Z axis. If the object is on my front and back, The rigidbody constraints lock the X axis.

[Hellium]

I have already given you a link to help you find the solution…

http://docs.unity3d.com/Manual/UnderstandingVectorArithmetic.html

You can easily use the dot product to know where the object is located
considering your player :

Dot product

Let’s define the vector between the player and the object :

Vector3 vector = object.transform.position - player.transform.position ;

Then , you have the following :

float forwardDotProduct = Vector3.Dot( player.transform.forward, vector ) ;
float rightDotProduct = Vector3.Dot( player.transform.right, vector ) ;

if( forwardDotProduct > 0.70f )
{
    // The object is in front of the player
}
else if( forwardDotProduct > 0 )
{
    // The object is on the right OR on the left
    if( rightDotProduct  > 0 )
        // The object is on the right
    else
        // The object is on the left
}
else
{
    // The object is behind the player
}