ó Š*Pc@s˜ddlmZmZmZmZddlmZddlmZddl m Z m Z m Z m Z mZe dZde Zdefd„ƒYZdS( iÿÿÿÿ(t GEOSGeometryt LinearRingtPolygontPoint(tGoogleMapException(txrange(tpitsintlogtexptatang€f@t GoogleZoomcBs\eZdZddd„Zd„Zd„Zd„Zd„Zd„Zd „Z d „Z RS( s GoogleZoom is a utility for performing operations related to the zoom levels on Google Maps. This class is inspired by the OpenStreetMap Mapnik tile generation routine `generate_tiles.py`, and the article "How Big Is the World" (Hack #16) in "Google Maps Hacks" by Rich Gibson and Schuyler Erle. `generate_tiles.py` may be found at: http://trac.openstreetmap.org/browser/applications/rendering/mapnik/generate_tiles.py "Google Maps Hacks" may be found at http://safari.oreilly.com/0596101619 iicCs˜||_||_g|_g|_g|_|}x^t|ƒD]P}|jj|dƒ|jj|dtƒ|jj|dƒ|d9}q@WdS(s#Initializes the Google Zoom object.g€v@iN(t _tilesizet_nzoomt_degppt_radppt_npixRtappendR(tselftnum_zoomttilesizetzti((s<../Django//lib/python/django/contrib/gis/maps/google/zoom.pyt__init__s     cCs|jS(s"Returns the number of zoom levels.(R (R((s<../Django//lib/python/django/contrib/gis/maps/google/zoom.pyt__len__3scCs7t|tƒr!|j\}}n |\}}||fS(s:Unpacks longitude, latitude from GEOS Points and 2-tuples.(t isinstanceRtcoords(Rtlonlattlontlat((s<../Django//lib/python/django/contrib/gis/maps/google/zoom.pyt get_lon_lat7s c Csž|j|ƒ\}}|j|}t|||j|ƒ}tttt|ƒdƒdƒ}t|dtd|d|ƒd|j |ƒ}||fS(sHConverts a longitude, latitude coordinate pair for the given zoom level.g§èH.ÿï¿g§èH.ÿï?gà?igð¿( RRtroundRtmintmaxRtDTORRR( RRtzoomRRtnpixtpx_xtfactpx_y((s<../Django//lib/python/django/contrib/gis/maps/google/zoom.pytlonlat_to_pixel?s  "5cCsŠt|ƒdkr!tdƒ‚n|j|}|d||j|}tdtt|d|d|j|ƒƒdt}||fS(sGConverts a pixel to a longitude, latitude pair at the given zoom level.is+Pixel should be a sequence of two elements.iigð¿gà?( tlent TypeErrorRRtRTODR R RR(RtpxR#R$RR((s<../Django//lib/python/django/contrib/gis/maps/google/zoom.pytpixel_to_lonlatVs  9cCs­|jd}|j||ƒ}|j|d||d|f|ƒ}|j|d||d|f|ƒ}tt||d|df||d|df|ƒddƒS(só Returns a Polygon corresponding to the region represented by a fictional Google Tile for the given longitude/latitude pair and zoom level. This tile is used to determine the size of a tile at the given point. iiitsridiæ(R R(R-RR(RRR#tdeltaR,tlltur((s<../Django//lib/python/django/contrib/gis/maps/google/zoom.pyttilegs  ((c CsÜt|tƒ s|jdkr.tdƒ‚n|j}|j|jƒ\}}|j}xvt|j ƒD]e}|j|j ||ƒjƒ\}}||ksª||krh|dkrÅt dƒ‚n|dSqhW|j dS(s6Returns the optimal Zoom level for the given geometry.iæs8get_zoom() expects a GEOS Geometry with an SRID of 4326.is>Geometry width and height should not exceed that of the Earth.i( RRR.R*tenvelopetget_width_heighttextenttcentroidRR R2R( Rtgeomtenvtenv_wtenv_htcenterRttile_wttile_h((s<../Django//lib/python/django/contrib/gis/maps/google/zoom.pytget_zoom|s  $  cCs_t|d ƒ}t|d|dƒ}t|dƒ}|j|ƒ}|j|ƒ}||fS(sD Returns the width and height for the given extent. iii(Rtdistance(RR5R0tulR1theighttwidth((s<../Django//lib/python/django/contrib/gis/maps/google/zoom.pyR4–s ( t__name__t __module__t__doc__RRRR(R-R2R>R4(((s<../Django//lib/python/django/contrib/gis/maps/google/zoom.pyR s       N(tdjango.contrib.gis.geosRRRRt#django.contrib.gis.maps.google.gmapRtdjango.utils.six.movesRtmathRRRR R R"R+tobjectR (((s<../Django//lib/python/django/contrib/gis/maps/google/zoom.pyts "(