Equivalent of getBoundsZoomLevel() in gmaps api 3 [duplicate]

Question

In API v2, the map object had a handy method getBoundsZoomLevel(). I used it to get the zoom level which fits the bounds best, then manipulated this optimal zoom level somehow and finally set the desired zoom level.

I cannot find similar function in API v3. (What a continuous frustrating experience when moving from v2 to v3)

Do I really have to use map.fitBounds(), map.getZoom(), manipulate and setZoom() again? That's really stupid!

Parlin

take a look at #6049475 – Loopy

Thanks @Dr.Molle. It's a pitty you must write your own function for that, so in this case I prefered the stupid solution I presented above. But I will use your link for another problem, thanks!! – Parlin

+1 - I'm surprised you haven't received more up-votes. – Posterior

what are you missing from map.fitBounds()? so far that seems to do a pretty good job centering the map on the bounds, and going to a zoom level thats fitting for the map size and bounds size – Corregidor

Answer 1

Below is a function I have implemented:

/**
* Returns the zoom level at which the given rectangular region fits in the map view. 
* The zoom level is computed for the currently selected map type. 
* @param {google.maps.Map} map
* @param {google.maps.LatLngBounds} bounds 
* @return {Number} zoom level
**/
function getZoomByBounds( map, bounds ){
  var MAX_ZOOM = map.mapTypes.get( map.getMapTypeId() ).maxZoom || 21 ;
  var MIN_ZOOM = map.mapTypes.get( map.getMapTypeId() ).minZoom || 0 ;

  var ne= map.getProjection().fromLatLngToPoint( bounds.getNorthEast() );
  var sw= map.getProjection().fromLatLngToPoint( bounds.getSouthWest() ); 

  var worldCoordWidth = Math.abs(ne.x-sw.x);
  var worldCoordHeight = Math.abs(ne.y-sw.y);

  //Fit padding in pixels 
  var FIT_PAD = 40;

  for( var zoom = MAX_ZOOM; zoom >= MIN_ZOOM; --zoom ){ 
      if( worldCoordWidth*(1<<zoom)+2*FIT_PAD < $(map.getDiv()).width() && 
          worldCoordHeight*(1<<zoom)+2*FIT_PAD < $(map.getDiv()).height() )
          return zoom;
  }
  return 0;
}

Neper

Thank you! Your code produces the same values as the old v2 getZoomByBounds – Employee

One can use (map.getDiv()).style.width instead of $(map.getDiv()).width(), same as height also. – Hautemarne

@Hautemarne I think you mean .offsetWidth and .offsetHeight (the style attributes may not be set) – Milburt

@Milburt Yes buddy, because sometimes $(map.getDiv()).width() returns undefined so one can go with (map.getDiv()).style.width also. – Hautemarne

I wondered it wasn't working in first place, but then I figured out it needed a "projection_changed"-Event Listener. Now it works like a charm. Just mentioning it if anyone else has the same problem. – Meingolda

I have been looking for this for over 3 hours. I even wrote a checker that would check random bounds and this function works out of the 20,000 random checks I've done. Seems to always match what google says the bounded zoom will be. – Zolazoldi

How can I give it padding in only one direction? lets say padding from bottom of map – Reitareiter