[OpenLayers-Users] What is the relationship between zoom level and longitude/latitude

[Adrian Popa]

Thank you all for your help,

I used zoomToExtent and it worked great...


Kenneth Skovhede, GEOGRAF A/S wrote:
> There is a function just for that:
> http://dev.openlayers.org/releases/OpenLayers-2.8/doc/apidocs/files/OpenLayers/Map-js.html#OpenLayers.Map.zoomToExtent 
>
>
> If you need the value, you can call this:
> http://dev.openlayers.org/releases/OpenLayers-2.8/doc/apidocs/files/OpenLayers/Map-js.html#OpenLayers.Map.getZoomForExtent 
>
>
> You can examine the code if you are interested in the inner workings 
> of calculating a zoom level from a rectangle.
>
> Regards, Kenneth Skovhede, GEOGRAF A/S
>
>
>
>
> Adrian Popa skrev:
>> Hello everybody.
>>
>> I'm trying to zoom to view an area for which I have the minimum and 
>> maximum longitude/latitude. Basically I would like to zoom in to see 
>> a rectangle with known coordinates. I already calculated the center 
>> of this rectangle - so that's not a problem - the map centers 
>> beautifully to that.
>>
>> The problem is: I have to find out which minimum zoom setting would 
>> allow my area to be fully visible - so I need to choose a zoom 
>> setting. There must be a relationship between the difference in 
>> longitude (or latitude) to a zoom level.
>>
>> I wonder if anyone knows this relationship - or should I determine it 
>> empirically.
>>
>> Thank you.
>>
>> By the way, my map is using spherical mercator projection, but my 
>> coordinates are in longitude/latitude (although there is no problem 
>> in converting them...).
>>
>>   
>