📡 implementing HTTP source handling for TileSource

package.json

@@ -1,12 +1,16 @@
 {
-  "name": "termap",
+  "name": "mapscii",
   "version": "0.1.0",
   "description": "Terminal Map Viewer",
-  "main": "termap.coffee",
+  "main": "main.js",
   "scripts": {
     "start": "node main",
     "test": "echo \"Error: no test specified\" && exit 1"
   },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/rastapasta/mapscii.git"
+  },
   "keywords": [
     "map",
     "console",
@@ -14,7 +18,6 @@
     "ascii",
     "osm",
     "vectortile",
-    "render",
     "mbtiles"
   ],
   "author": "Michael Straßburger <codepoet@cpan.org>",
@@ -29,6 +32,8 @@
     "mbtiles": "^0.9.0",
     "pbf": "^3.0.0",
     "rbush": "^2.0.1",
+    "request": "^2.76.0",
+    "request-promise": "^4.1.1",
     "sphericalmercator": "^1.0.5",
     "term-mouse": "^0.1.1",
     "vector-tile": "^1.3.0",

src/Renderer.coffee

@@ -178,22 +178,6 @@ module.exports = class Renderer
   featuresAt: (x, y) ->
     @labelBuffer.featuresAt x, y
 
-  _getBBox: (center, zoom) ->
-    [x, y] = utils.ll2xy center.lon, center.lat
-    meterPerPixel = utils.metersPerPixel zoom, center.lat
-
-    width = @width * meterPerPixel
-    height = @height * meterPerPixel
-
-    west = x - width*.5
-    east = x + width*.5
-    south = y + height*.5
-    north = y - height*.5
-
-    box = mercator
-    .inverse([west+1, south])
-    .concat mercator.inverse([east-1, north])
-
   _tilesInBBox: (bbox, zoom) ->
     tiles = {}
     [tiles.minX, tiles.minY] = utils.ll2tile bbox[0], bbox[1], Math.floor zoom

src/Termap.coffee

@@ -8,7 +8,6 @@
 keypress = require 'keypress'
 TermMouse = require 'term-mouse'
 Promise = require 'bluebird'
-mercator = new (require('sphericalmercator'))()
 
 Renderer = require './Renderer'
 TileSource = require './TileSource'
@@ -19,7 +18,8 @@ module.exports = class Termap
     input: process.stdin
     output: process.stdout
 
-    source: __dirname+"/../mbtiles/regensburg.mbtiles"
+    source: "http://nachbar.io/data/osm2vectortiles/"
+    #source: __dirname+"/../mbtiles/regensburg.mbtiles"
     styleFile: __dirname+"/../styles/bright.json"
     zoomStep: 0.2
 

src/TileSource.coffee

@@ -10,6 +10,9 @@
 Promise = require 'bluebird'
 MBTiles = require 'mbtiles'
 
+request = require 'request'
+rp = require 'request-promise'
+
 Tile = require './Tile'
 
 module.exports = class TileSource
@@ -17,15 +20,20 @@ module.exports = class TileSource
   modes:
     MBTiles: 1
     VectorTile: 2
+    HTTP: 3
 
   mode: null
 
   mbtiles: null
 
-  init: (source) ->
+  init: (@source) ->
-    if source.endsWith ".mbtiles"
+    if @source.startsWith "http"
+      @mode = @modes.HTTP
+
+    else if @source.endsWith ".mbtiles"
       @mode = @modes.MBTiles
       @loadMBtils source
+
     else
       throw new Error "source type isn't supported yet"
 
@@ -44,13 +52,23 @@ module.exports = class TileSource
     if cached = @cache[[z,x,y].join("-")]
       return Promise.resolve cached
 
-    if @mode is @modes.MBTiles
+    switch @mode
-      @_getMBTile z, x, y
+      when @modes.MBTiles then @_getMBTile z, x, y
+      when @modes.HTTP then @_getHTTP z, x, y
+
+  _getHTTP: (z, x, y) ->
+    rp
+      uri: @source+[z,x,y].join("/")+".pbf"
+      encoding: null
+    .then (buffer) =>
+      @_createTile z, x, y, buffer
 
   _getMBTile: (z, x, y) ->
     new Promise (resolve, reject) =>
-      @mbtiles.getTile z, x, y, (err, tileData) =>
+      @mbtiles.getTile z, x, y, (err, buffer) =>
         return reject err if err
+        resolve @_createTile z, x, y, buffer
 
+  _createTile: (z, x, y, buffer) ->
     tile = @cache[[z,x,y].join("-")] = new Tile()
-        resolve tile.load tileData
+    tile.load buffer

src/utils.coffee

@@ -4,6 +4,7 @@
 
   methods used all around
 ###
+mercator = new (require('sphericalmercator'))()
 
 constants =
   RADIUS: 6378137
@@ -42,6 +43,22 @@ utils =
     lon: x/Math.pow(2, zoom)*360-180
     lat: 180/Math.PI*Math.atan(0.5*(Math.exp(n)-Math.exp(-n)))
 
+  geoBBox: (center, zoom, width, height) ->
+    [x, y] = utils.ll2xy center.lon, center.lat
+    meterPerPixel = utils.metersPerPixel zoom, center.lat
+
+    width *= meterPerPixel
+    height *= meterPerPixel
+
+    west = x - width*.5
+    east = x + width*.5
+    south = y + height*.5
+    north = y - height*.5
+
+    box = mercator
+    .inverse([west+1, south])
+    .concat mercator.inverse([east-1, north])
+
   metersPerPixel: (zoom, lat = 0) ->
     (Math.cos(lat * Math.PI/180) * 2 * Math.PI * constants.RADIUS) / (256 * Math.pow(2, zoom))
 
@@ -70,4 +87,5 @@ utils =
   digits: (number, digits) ->
     Math.floor(number*Math.pow(10, digits))/Math.pow(10, digits)
 
+
 module.exports = utils