How to map deviceorientation to MozOrientation values

I have previously created a labyrinth game which works with Firefox's MozOrientation. I am now looking into getting it working with WebKit also...

But Webkit uses the w3c's DeviceOrientation. The values appear to be totally different, but someone must have some algorithm to get it from one to the other? Or am I missing something simple?

The labyrinth game with github link http://playground.marmaladeontoast.co.uk/labyrinth/

MozOrientation https://developer.mozilla.org/en/Detecting_device_orientation

DeviceOrientation http://dev.w3.org/geo/api/spec-source-orientation.html

Some sample values I have obtained:

Chrome

alpha = null      开发者_如何转开发                              
beta = -178 
gamma = 4.57    

Firefox

x = 0.035999998450279236
y = -0.02800000086426735
z = 1

Any help would be greatly appreciated :)

I've been playing around with this a bit. The source below 'maps' both alternatives to an understandable degrees range for x/gamma and y/beta.

The MozOrientation.z value is completely different from the deviceorientation.alpha value. The first returns the vertical orientation, the latter returns a sort of compass value. These values are therefor not interchangable / convertible.

function displayOrientation(orientData){

    var x = Math.round(orientData.x);
    var y = Math.round(orientData.y);
    var z = orientData.z;

    document.getElementById('x').value = x;
    document.getElementById('y').value = y;
    document.getElementById('z').value = z;
}

window.addEventListener("MozOrientation", function(orientData){

    var obj = {};
    obj.x = orientData.x * 90;
    obj.y = orientData.y * 90;
    obj.z = orientData.z;

    displayOrientation(obj);

}, true);

window.addEventListener("deviceorientation", function(orientData) {

    var obj = {};
    obj.x = orientData.gamma;
    obj.y = orientData.beta;
    obj.z = orientData.alpha;

    displayOrientation(obj);

}, true);

It seems the current desktop Safari (5.0.3) doesn't support this event at all. The beta value in desktop Chrome 9 is exactly 180 less than it is in mobile Safari. The x & y values in Firefox and mobile Safari should be approximately the same.

I hope that this codes clarify everything. Although the values this code returns can't be matched directly with the values of beta and gamma:

Mozilla returns the sin of the angle so, to get the angle...

X: Math.asin(eventInfo.x)*180/Math.PI
Y: Math.asin(eventInfo.y)*180/Math.PI
Z: Math.asin(eventInfo.z)*180/Math.PI

Webkit returns the acceleration in each axe. Then, to get the angle... (The sing changes is just to unify returned values)

X: Math.asin(clean(eventInfo.accelerationIncludingGravity.x/GRAVITY))*180/Math.PI
Y: Math.asin(clean(-eventInfo.accelerationIncludingGravity.y/GRAVITY))*180/Math.PI
Z: Math.asin(clean(-eventInfo.accelerationIncludingGravity.z/GRAVITY))*180/Math.PI

Being clean: (Because sometimes, the data returned, even without accelerating the phone, it's more than 9.8)

function clean(data)
{
    if(data<-1.0)
    {
        return -1.0; 
    }
    else
    {if(data>1.0)
    {
       return 1.0;
    }else
    {
        return data;
    }}
}

The meaning of each axe is: X-> inclination of the mobile to its right or left. Will be + if you tilt the mobile to its right (clockwise), keeping the buttons of volume up. Y-> Tells if the mobile is up -if the lock/on-off button is up- (angle +) or down (angle -). It tells the inclination of the mobile relative to the floor. (angle of Y vector with plane X-Z) Z-> Tells if the mobile screen is facing up (angle +) or upside down (angle -). It's the angle of the Z vector on the plane Y-X

Hope this is worthy for you!

Anyway, I'm working on some GWT classes to make working with this easier :) It's not difficult but I do not have so much time. I'll tell you

You should be able to calculate one according to the other. The problem I see is that Mozilla doesn't tell what means the data it returns. I'm working now with three mobile devices: ipad, iphone4 and nokia n900. When I work with iOS and safari and I get the accelerationIncludingGravity, I get values from -9.8 to 9.8. Those are values of the gravity that affect each axe. Then using trigonometry, I can calculate the angle in each axe. If I get orientation in the iphone4, I can get directly the angle in each axe.

The problem comes with nokia n900, whose browser is based in Mozilla. That browser only returns data from -1 to 1. Documentation says that it's the tilt of each axe. In what unities? Cosine? Or just angle/180? I guess that it's the cosine as when I put it in horizontal, it returns 0, and when I put it in vertical, it gets 1. And upside down, returns -1. Moreover, If you tilt it in aprox 60degrees, it returns 1/2.

As far I've seen, when using a Macbook laptop with Firefox, the data x,y and z is get as the cosine.

Mozilla Firefox now fully supports the W3C DeviceOrientation Events API. You should not use MozOrientation in your web applications any more.