Account for partial tiles in conversions to and from geographical coordinates

git-svn-id: file:///svnroot/wifihood/trunk/wifiscanner@13 c51dfc6a-5949-4919-9c8e-f207a149c383

diff --git a/wifiview b/wifiview
index 4a6bbe8..f8cd667 100755 (executable)
--- a/wifiview
+++ b/wifiview
@@ -42,29 +42,35 @@ class mapWidget ( gtk.Image , WifihoodConfig ) :
 
     # Maximum width should be 800, but actually gets reduced
     self.win_x , self.win_y = 800 , 480
+    self.tile_size = 256
 
     p = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, True, 8, self.win_x, self.win_y)
     self.set_from_pixbuf(p)
 
     self.read()
-    self.reftile_x , self.reftile_y = self.lon2tilex( self.lon , self.zoom ) , self.lat2tiley( self.lat , self.zoom )
-    # Half the size of a tile
-    self.refpix_x , self.refpix_y = 128 , 128
+    self.reftile_x , self.refpix_x = self.lon2tilex( self.lon , self.zoom )
+    self.reftile_y , self.refpix_y = self.lat2tiley( self.lat , self.zoom )
 
     self.composeMap()
 
   def lon2tilex ( self , lon , zoom ) :
-    return int( ( lon + 180 ) / 360 * 2 ** zoom )
+    number = math.modf( ( lon + 180 ) / 360 * 2 ** zoom )
+    return int( number[1] ) , int( self.tile_size * number[0] )
 
   def lat2tiley ( self , lat , zoom ) :
     lat = lat * math.pi / 180
-    return int( ( 1 - math.log( math.tan( lat ) + 1 / math.cos( lat ) ) / math.pi ) / 2 * 2 ** zoom )
-
-  def tilex2lon ( self , tilex , zoom ) :
-    return tilex / 2.0 ** zoom * 360.0 - 180.0
-
-  def tiley2lat ( self , tiley , zoom ) :
-    tiley = math.pi * ( 1 - 2 * tiley / 2.0 ** zoom )
+    number = math.modf( ( 1 - math.log( math.tan( lat ) + 1 / math.cos( lat ) ) / math.pi ) / 2 * 2 ** zoom )
+    return int( number[1] ) , int( self.tile_size * number[0] )
+
+  def tilex2lon ( self , ( tilex , pixx ) , zoom ) :
+    tilex = float(tilex)
+    pixx = float(pixx)
+    return ( tilex + pixx/self.tile_size ) / 2.0 ** zoom * 360.0 - 180.0
+
+  def tiley2lat ( self , ( tiley , pixy ) , zoom ) :
+    tiley = float(tiley)
+    pixy = float(pixy)
+    tiley = math.pi * ( 1 - 2 * ( tiley + pixy/self.tile_size ) / 2.0 ** zoom )
     return math.degrees( math.atan( math.sinh( tiley ) ) )
 
   def composeMap( self ) :
@@ -80,7 +86,7 @@ class mapWidget ( gtk.Image , WifihoodConfig ) :
       for j in range(-3,4) :
         file = self.tilename( i , j , self.zoom )
         if file is None :
-          pixbuf = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, False, 8, 256, 256 )
+          pixbuf = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, False, 8, self.tile_size, self.tile_size )
           pixbuf.fill( 0x00000000 )
         else :
           try :
@@ -94,30 +100,30 @@ class mapWidget ( gtk.Image , WifihoodConfig ) :
               pixbuf = gtk.gdk.pixbuf_new_from_file( file )
             except :
               print "Total failure for tile for %s,%s" % ( self.reftile_x + i , self.reftile_y + j )
-              pixbuf = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, False, 8, 256, 256 )
+              pixbuf = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, False, 8, self.tile_size, self.tile_size )
 
-        dest_x = 256 * i + center_x
-        dest_y = 256 * j + center_y
+        dest_x = self.tile_size * i + center_x
+        dest_y = self.tile_size * j + center_y
 
         init_x = 0
-        size_x = 256
+        size_x = self.tile_size
         if dest_x < 0 :
            init_x = abs(dest_x)
-           size_x = 256 + dest_x
+           size_x = self.tile_size + dest_x
            dest_x = 0
-        if dest_x + 256 > self.win_x :
+        if dest_x + self.tile_size > self.win_x :
            size_x = self.win_x - dest_x
 
         init_y = 0
-        size_y = 256
+        size_y = self.tile_size
         if dest_y < 0 :
            init_y = abs(dest_y)
-           size_y = 256 + dest_y
+           size_y = self.tile_size + dest_y
            dest_y = 0
-        if dest_y + 256 > self.win_y :
+        if dest_y + self.tile_size > self.win_y :
            size_y = self.win_y - dest_y
 
-        if ( size_x > 0 and size_y > 0 ) and ( init_x < 256 and init_y < 256 ) :
+        if ( size_x > 0 and size_y > 0 ) and ( init_x < self.tile_size and init_y < self.tile_size ) :
             pixbuf.copy_area( init_x, init_y, size_x, size_y, self.get_pixbuf(), dest_x , dest_y )
         del(pixbuf)
 
@@ -154,23 +160,23 @@ class mapWidget ( gtk.Image , WifihoodConfig ) :
   def Shift( self , dx , dy ) :
     self.hide()
 
-    tile_x , tile_y = ( self.refpix_x - dx ) / 256 , ( self.refpix_y - dy ) / 256
+    tile_x , tile_y = ( self.refpix_x - dx ) / self.tile_size , ( self.refpix_y - dy ) / self.tile_size
     self.reftile_x += tile_x
     self.reftile_y += tile_y
 
-    self.refpix_x -= dx + 256 * tile_x
-    self.refpix_y -= dy + 256 * tile_y
+    self.refpix_x -= dx + self.tile_size * tile_x
+    self.refpix_y -= dy + self.tile_size * tile_y
 
     self.composeMap()
     self.show()
 
   def SetZoom( self , zoom ) :
     self.hide()
-    lat = self.tiley2lat( self.reftile_y , self.zoom )
-    lon = self.tilex2lon( self.reftile_x , self.zoom )
-    self.reftile_x , self.reftile_y = self.lon2tilex( lon , zoom ) , self.lat2tiley( lat , zoom )
+    lat = self.tiley2lat( ( self.reftile_y , self.refpix_y ) , self.zoom )
+    lon = self.tilex2lon( ( self.reftile_x , self.refpix_x ) , self.zoom )
+    self.reftile_x , self.refpix_x = self.lon2tilex( lon , zoom )
+    self.reftile_y , self.refpix_y = self.lat2tiley( lat , zoom )
     self.zoom = zoom
-    self.refpix_x , self.refpix_y = 128 , 128
     self.composeMap()
     self.show()