1

Hi guys
any one know, how this MoveTowards() function works ? whats the maths behind this function ?

I was trying to create a function to move my character from current position to a target position in X,Y plane, Let me tell you i am not good in maths. And than i found this function which does the same thing cheers. but i would love to know the maths behind this function.
So, Please help me understand whats happening in this MoveTowards() function.

thanks

4

This is the actual code behind the function :wink:

// Vector3.MoveTowards
public static Vector3 MoveTowards(Vector3 current, Vector3 target, float maxDistanceDelta)
{
    Vector3 a = target - current;
    float magnitude = a.magnitude;
    if (magnitude <= maxDistanceDelta || magnitude == 0f)
    {
        return target;
    }
    return current + a / magnitude * maxDistanceDelta;
}

Just in case you didn’t ment Vector3.MoveTowards, here’s Mathf.MoveTowards:

// Mathf.MoveTowards
public static float MoveTowards(float current, float target, float maxDelta)
{
    if (Mathf.Abs(target - current) <= maxDelta)
    {
        return target;
    }
    return current + Mathf.Sign(target - current) * maxDelta;
}
2

The basic calculation is:

newPos = startPos + (endPos - startPos).normalized * maxDist;

If you want it to go no further than the endPos, you will need to clamp the distance you use.

3

It figures out the direction you are moving towards, and adds direction * maxDistanceDelta. If the remaining distance is less than maxDistanceDelta, then it simply returns the target.

if (remainingDistance <= maxDistanceDelta)
    return target;
else 
    return current + directionToTarget * maxDistanceDelta;

That’s pretty much how it works.