add gps

luci-app-gpoint-main/root/usr/share/gpoint/lib/geohash.lua

@@ -0,0 +1,147 @@
+-- Geohash
+-- (c) 2015 Ivan Ribeiro Rocha (ivan.ribeiro@gmail.com)
+-- (c) 2022 modified by Vladislav Kadulin (spanky@yandex.ru)
+
+local bit = require("bit32")
+
+geohash = {}
+
+local BITS = { 16, 8, 4, 2, 1 }
+local BASE32 = "0123456789bcdefghjkmnpqrstuvwxyz"
+
+local NEIGHBORS = { right  = { even = "bc01fg45238967deuvhjyznpkmstqrwx" },
+                    left   = { even =  "238967debc01fg45kmstqrwxuvhjyznp" },
+                    top    = { even =  "p0r21436x8zb9dcf5h7kjnmqesgutwvy" },
+                    bottom = { even = "14365h7k9dcfesgujnmqp0r2twvyx8zb" } }
+
+local BORDERS = { right  = { even = "bcfguvyz" },
+                  left   = { even = "0145hjnp" },
+                  top    = { even = "prxz" },
+                  bottom = { even = "028b" } }
+
+NEIGHBORS.bottom.odd = NEIGHBORS.left.even
+NEIGHBORS.top.odd    = NEIGHBORS.right.even
+NEIGHBORS.left.odd   = NEIGHBORS.bottom.even
+NEIGHBORS.right.odd  = NEIGHBORS.top.even
+
+BORDERS.bottom.odd   = BORDERS.left.even
+BORDERS.top.odd      = BORDERS.right.even
+BORDERS.left.odd     = BORDERS.bottom.even
+BORDERS.right.odd    = BORDERS.top.even
+
+function geohash.decode(hash)
+    local flip = true;
+    local coords = { latitude = { -90.0, 90.0 },
+                     longitude = { -180.0, 180.0 } }
+
+    for i = 1, #hash do
+        local c = hash:sub(i, i)
+        local cd = BASE32:find(c) - 1
+        for j = 1, 5 do
+            mask = BITS[j]
+            local tab = (flip and coords.longitude) or coords.latitude
+            local idx = (bit.band(cd, mask) > 0) and 1 or 2
+            tab[idx] = (tab[1] + tab[2]) / 2
+            flip = not flip
+        end
+    end
+
+    for k, _ in pairs(coords) do
+        coords[k][3] = (coords[k][1] + coords[k][2]) / 2
+    end
+
+    return { lat = coords.latitude, lon = coords.longitude }
+
+end
+
+function geohash.encode(latitude, longitude, precision)
+    local lat = { -90.0, 90.0 }
+    local lon = { -180.0, 180.0 }
+    local b, ch, flip = 0, 0, true
+    local res = "";
+
+    latitude  = tonumber(latitude)
+    longitude = tonumber(longitude)
+    precision = tonumber(precision)
+    local precision = precision or 12
+
+    while #res < precision do
+        local tab = flip and lon or lat
+        local grd = flip and longitude or latitude
+        
+        mid = (tab[1] + tab[2]) / 2
+
+        if grd > mid then
+            ch = bit.bor(ch, BITS[b + 1])
+            tab[1] = mid
+        else
+            tab[2] = mid
+        end
+
+        flip = not flip;
+
+        if b < 4 then
+            b = b + 1
+        else
+            res = res..BASE32:sub(ch + 1, ch + 1);
+            b, ch = 0, 0
+        end
+    end
+    return res
+end
+
+function geohash.calculate_distance(lat1, lon1, lat2, lon2)
+    local R = 6371000
+    local r1, r2 = math.rad(lat1), math.rad(lat2)
+    local dlat, dlon = math.rad((lat2-lat1)), math.rad((lon2-lon1))
+    local a = math.sin(dlat/2) * math.sin(dlat/2) +
+              math.cos(r1) * math.cos(r2) *
+              math.sin(dlon/2) * math.sin(dlon/2)
+    local c = 2 * math.atan2(math.sqrt(a), math.sqrt(1-a))
+    return R * c
+end
+
+function geohash.distance(hash1, hash2)
+    local t1, t2 = decode(hash1), decode(hash2)
+    return calculate_distance(coord(t1).lat, coord(t1).lon,
+                              coord(t2).lat, coord(t2).lon)
+end
+
+function geohash.neighbor(hash, dir)
+    hash = hash:lower()
+    local len = #hash
+    local last = hash:sub(len, len);
+    local flip = ((math.mod(len,2) == 0) and 'even') or 'odd'
+    local base = hash:sub(1, len - 1)
+    if BORDERS[dir][flip]:find(last) then
+        base = neighbor(base, dir)
+    end
+    local n = NEIGHBORS[dir][flip]:find(last)
+    return base..BASE32:sub(n, n)
+end
+
+function geohash.neighbors(hash)
+    local neighbors = { top = neighbor(hash, 'top'),
+                        bottom = neighbor(hash, 'bottom'),
+                        right = neighbor(hash, 'right'),
+                        left = neighbor(hash, 'left') }
+    neighbors.topleft = neighbor(neighbors.left, 'top');
+    neighbors.topright = neighbor(neighbors.right, 'top');
+    neighbors.bottomleft = neighbor(neighbors.left, 'bottom');
+    neighbors.bottomright = neighbor(neighbors.right, 'bottom');
+    return neighbors
+end
+
+function geohash.coord(t)
+    if type(t) == 'table' then
+        return { lat = t.lat[3], lon = t.lon[3] }
+    end
+    return coord(decode(t))
+end
+
+function geohash.coord_str(t)
+    local t = coord(t)
+    return string.format("lat: %s and lon: %s", tostring(t.lat), tostring(t.lon))
+end
+
+return geohash