pass zoom level to canvas

pkgs/maps/tiles.fnl

@@ -59,7 +59,7 @@
       ]
      (table.concat  "\n"))))
 
-(fn canvas [elements]
+(fn canvas [elements zoom]
   (let [nodes {}
         lines {}]
     (each [_ e (ipairs elements)]
@@ -71,7 +71,7 @@
          e.id
          (icollect [_ nd (ipairs e.nodes)]
            (let [node (. nodes nd)
-                 (tx ty) (latlon->tile node.lat node.lon 17)]
+                 (tx ty) (latlon->tile node.lat node.lon zoom)]
              ;;(print e.tags.name e.id e.name node.lat node.lon)
              [ tx ty  ])))))
     lines))
@@ -111,7 +111,7 @@
         (let [data (with-open [i (io.open pathname :r)] (i:read "*a"))]
           (if (= data "")
               []
-              (canvas (. (json.decode data) :elements))))
+              (canvas (. (json.decode data) :elements) zoom)))
         (let [out (io.open pathname :w)]
           (cq:wrap (fn []
                      (print "getting " k)