Find the value on wheel for wheel of fortune

Question

I have an image of a wheel of fortune wheel and I am trying to make so that when it spins it displays the correct amount for what it was spun to. I have the following code: http://jsfiddle.net/maniator/rR67s/ Many times it is correct, and other time is is wrong. For example I spun this: And it alerted 300, which is wrong. How can I fix my algorithm so that it is correct 99% of the time (or 100% if it is possible)? HTML: ```

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``` Javascript: ``` var Wheel = (function () { var wheel = document.getElementById('wheel'), wheelValues = [5000, 600, 500, 300, 500, 800, 550, 400, 300, 900, 500, 300, 900, 0, 600, 400, 300, -2, 800, 350, 450, 700, 300, 600], spinTimeout = false, spinModifier = function () { return Math.random() * 10 + 20; }, modifier = spinModifier(), slowdownSpeed = 0.5, prefix = (function () { if (document.body.style.MozTransform !== undefined) { return "MozTran…

Accepted Answer

I think the problem is that the arrow in the starting position is in the middle of a zone, not at the start of it. So you have a starting offset of `(360 / wheelValues.length)/2`

```
var divider = 360 / wheelValues.length;
var offset=divider/2; //half division
var wheelValue = wheelValues[Math.floor(Math.ceil((dataRotation+offset) % 360) / divider)];
```

This seems to work: when the wheel stops either at the beginning (first half) or at the end (last half) of a zone the showed value is the expected one (just about a dozen tests done)

Find the value on wheel for wheel of fortune

Solution

Problem