# Calculating distance from center of a circle(e.g. archery board)

Discussion in 'Physics' started by sami1592, Dec 10, 2014.

1. ### sami1592

Joined:
Sep 18, 2013
Posts:
50
Suppose i have a 2d archery game(silly, i know). Player's job is to tap the moving circular archery board. Depending of the accuracy of the tap the player will get a score. More the center is the tap, the more is the score.
So, after determining if the tap is within the circle I have to calculate the tap accuracy(by accuracy i mean how close is the tap from the center of the circle)

So, how to calculate the distance from the center of the circle to a specific point? .

2. ### dterbeest

Joined:
Mar 23, 2012
Posts:
382
Vector2.Distance(center, le_random_point);
or
Vector3.Distance(center, le_random_point);

3. ### sami1592

Joined:
Sep 18, 2013
Posts:
50
tnx, i know that part. but how can i know my tap is in the circle or not?

4. ### MikeUpchat

Joined:
Sep 24, 2010
Posts:
873
But that was your question, how to calculate the distance Clearly if the distance is greater than the radius of your circle the tap is outside, if less it is inside.

NareshKhandla likes this.
5. ### cl9

Joined:
May 31, 2013
Posts:
417
You could do something such as worldPosition = camera.ScreenToWorldPoint(tapPosition) where tapPosition's z component is equal to the target's z component. Then you could get the distance between the target's center and the tap point using Vector3.Distance(tapPosition, targetPosition).