change: move calclation functions to data processing, add: grid calculation

server/data_processing/area_processing.py

+from math import pi, cos
+
+EARTH = 6378.137  # Radius of the earth in kilometer
+METER = (1 / ((2 * pi / 360) * EARTH)) / 1000  # 1 meter in degree
+
+def calculate_corners(lat, lng, area_offset):
+    """Calculate corners of polygon based on a center coordinate
+
+    Arguments:
+    lat -- center latitude
+    lng -- center longitude
+    """
+    # From https://stackoverflow.com/questions/7477003/calculating-new-longitude-latitude-from-old-n-meters
+    # Formulas:
+    lat_pos = lat + (area_offset * METER)
+    lng_pos = lng + (area_offset * METER) / cos(lat * (pi / 180))
+
+    lat_neg = lat - (area_offset * METER)
+    lng_neg = lng - (area_offset * METER) / cos(lat * (pi / 180))
+
+    return [
+        (lat_neg, lng_pos), # top left
+        (lat_pos, lng_pos), # top right
+        (lat_pos, lng_neg), # bottom right
+        (lat_neg, lng_neg)  # bottom left
+    ]
+    '''return [(60.7798, 10.7062),  # NB: temporary hardcoded values
+            (60.7553, 10.7433),
+            (60.7718, 10.7975),
+            (60.7966, 10.7405)]'''
+
+def define_gridareas(lat, lng, area_offset, grid_size):
+    return_value = []
+    main_area = calculate_corners(lat, lng, area_offset)
+    area_size = (main_area[0][0] - main_area[2][0], main_area[0][1] - main_area[2][1])
+    dist_to_subcenter = (area_size[0]/(grid_size*2), area_size[1]/(grid_size*2))
+    subarea_offset = area_offset/grid_size
+    print(area_size)
+    print(dist_to_subcenter)
+    for y in range(grid_size-1):
+        relative_size_lng = y / grid_size
+        for x in range(grid_size-1):
+            relative_size_lat = x / grid_size
+            lat_pos = main_area[0][0] + relative_size_lat * area_size[0] - dist_to_subcenter[0]
+            lng_pos = main_area[0][1] + relative_size_lng * area_size[1] - dist_to_subcenter[1]
+            return_value.append(calculate_corners(lat_pos, lng_pos,subarea_offset))
+
+    return return_value
+
+print(calculate_corners(60,10,1500))
+print(define_gridareas(60,10,1500,4))
\ No newline at end of file

server/map/get_markers.py

 import json
-from math import pi, cos
-
 
 # get_markers requests all marker data or valid markers, converts the data to json, and writes
 # the data to the response object
@@ -91,37 +89,3 @@ def get_all_markers(self, cursor, valid: bool, waterBodyName):
 
     # Write marker data to response object
     self.wfile.write(marker_data.encode('utf-8'))
-
-
-EARTH = 6378.137  # Radius of the earth in kilometer
-METER = (1 / ((2 * pi / 360) * EARTH)) / 1000  # 1 meter in degree
-OFFSET = 20  # Offset in meters
-
-
-def calculate_corners(lat, lng):
-    """Calculate corners of polygon based on a center coordinate
-
-    Arguments:
-    lat -- center latitude
-    lng -- center longitude
-    """
-    # From https://stackoverflow.com/questions/7477003/calculating-new-longitude-latitude-from-old-n-meters
-    # Formulas:
-    '''
-    lat_pos = lat + (OFFSET * METER)
-    lng_pos = lng + (OFFSET * METER) / cos(lat * (pi / 180))
-
-    lat_neg = lat - (OFFSET * METER)
-    lng_neg = lng - (OFFSET * METER) / cos(lat * (pi / 180))
-
-    return [
-        (lat_neg, lng_pos),
-        (lat_pos, lng_pos),
-        (lat_pos, lng_neg),
-        (lat_neg, lng_neg)
-    ]    '''
-
-    return [(60.7798, 10.7062),  # NB: temporary hardcoded values
-            (60.7553, 10.7433),
-            (60.7718, 10.7975),
-            (60.7966, 10.7405)]