maplib.py 文件源码

def init_grid(self):
        grid_all = []
        lats = self.init_lats()
        c = 2 * pi / (3 ** 0.5 * self.r_sight * self.safety) * self.earth_R

        even_lng = True

        strip_amount = int(ceil(c))
        grid_all.append((0, strip_amount, even_lng))
        ind_lat = 2

        while ind_lat < len(lats):
            amount = int(ceil(c * cos(lats[ind_lat])))
            if amount < strip_amount - (sin(lats[ind_lat]*2)*self.param_shift+self.param_stretch):
                ind_lat -= 1
                strip_amount = int(ceil(c * cos(lats[ind_lat])))
            else:
                even_lng = not even_lng

            if ind_lat + 1 < len(lats):
                lat = lats[ind_lat + 1] * 180 / pi
                grid_all.append((lat, strip_amount, even_lng))
            ind_lat += 3

        grid_all.append((90.0, 1, True))  # pole

        return grid_all