Google Maps InfoBubble pixelOffset (Moving from default position above marker)

Question

I am trying to implement a custom infoBubble that has the box opening to the side of a marker rather than the default position of on top. This has turned out to be harder than e

Answer 1

It seems as though the infoBubble library itself defaults to positioning the bubble above the marker it is bound to. Take a look at the sample file they included in the library: http://code.google.com/p/google-maps-utility-library-v3/source/browse/trunk/infobubble/examples/example.html . Specifically notice from line 99 to line 122 and the use of the two infobubbles. The first one is bound to the marker, however the second one is a stand-alone and thus if you see line 106, you can define a position to it. Now, based on this understanding I've created an example for you in this fiddle http://jsfiddle.net/pDFc3/. The infoBubble is positioned to the right of the marker.

It's strange, because the infoBubble js library has a function for setPosition ( http://code.google.com/p/google-maps-utility-library-v3/source/browse/trunk/infobubble/src/infobubble.js?r=206 ) see Line 1027. But for some reason after I wait for the DOM to load and try to change the position by going infoBubble.setPosition(newLatLng); I doesn't work. On the contrary, declaring infoBubble.getPosition(); after the DOM loads gives me the current position of the marker the infoBubble is bound to. So setPosition() may have a bug in the js library, because I believe it is still being worked on (I could be wrong maybe it's just buggy).

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I've fixed my jsFiddle to solve your issue for when zooming in and out, and positioning the infoBubble accordingly ( http://jsfiddle.net/pDFc3/ ). Let me explain the logic first. Firstly, the maximum zoom level on Google Maps for road map type is 21 - this value is inconsistent for satellite imagery but the maximum zoom the user can go to is 21. From 21, each time you zoom out the differences between two points can be kept consistent "on screen" based on the following logic:

consitent_screen_dist = initial_dist * (2 ^ (21 - zoomlevel))

In our case, the reasonable value for initial distance was 0.00003 degrees (between marker and infoBubble). So, based on this logic I added the following piece to find the initial longitudinal distance between marker and infoBubble:

var newlong = marker.getPosition().lng() + (0.00003 * Math.pow(2, (21 - map.getZoom())));

Likewise, to ensure the distance stays consistent on each zoom level change we simply declare a new longitude as we listen for a change in the zoom level:

    google.maps.event.addListener(map, "zoom_changed", function() {
        newlong = marker.getPosition().lng() + (0.00003 * Math.pow(2, (21 - map.getZoom())));
        infoBubble.setPosition(new google.maps.LatLng(marker.getPosition().lat(), newlong));                
    });

Keep in mind you can make this code much more efficient by declaring variables for marker.getPosition and other values that are called through methods. So that the method calls aren't repeated and slow your code down.