[OpenLayers-Users] Finding the closest feature

[Christopher Schmidt]

On Thu, Oct 08, 2009 at 10:56:55AM -0400, Jesse Bushkar wrote:
> I have a question about finding the nearest feature from any given point.  I
> have a map with several featues, and I have a point somewhere on that map
> that represents my location.  Is there a function I can call that will look
> at the existing features in the layer and output the marker?  I'm
> envisioning something like this:
> 
> var nearPoint = findClosest(myLoc);
> var dist = myLoc.distanceTo(nearPoint);
> alert(dist);
> 
> I guess the way to perform that fake findClosest function is what I'm
> looking for.  I'd rather not have to measure individual features, because
> these features are being dynamically added, removed, and modified on a map
> at any given time.  SO, to simply shuffle through all features at the time
> of the function call would be GREAT!

var min = 1000000000000000;
var minFeat = null;
for (var i = 0; i < layer.features; i++) {
    var dist = Math.sqrt(
        Math.pow(myLoc.geometry.x - layer.features[i].geometry.x, 2) + 
        Math.pow(myLoc.geometry.y - layer.features[i].geometry.y, 2))
    if (dist < min) {
        minFeat = layer.features[i]; 
        min = dist;
    }
}
return minFeat;

> Thanks in advance for any help.

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-- 
Christopher Schmidt
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