some notes about tiles

README

@@ -79,9 +79,6 @@ elapsed time: what should it actually show? moving time, I guess
 
 should we rename bearing as course in nmea?
 
-perhaps we need a server-side component for route planning
-
-
 7) think about how to use nfc tags or something for profiles so that
 it can recognise when it's attached to bicycle or motorbike
 
@@ -110,40 +107,30 @@ cover more than 1/16th the length of the tile"
 
 d) render ways according to their type (road/cycleway/path/etc)
 
-e) label the ways
-
-f) async tile fetching
-
-we don't want everything to stop when it's time to fetch a new
-row of tiles, what are our options? lua-http is built on cqueues
-which is async enough to make my head hurt, but we also need
-to make it coexist with the gtk event loop
-
-assumptions:
-1) gtk stuff has to happen in the main thread (whatever that is...)
-so we can't control it from cqueues because that has its own
-threading stuff
-2) there will be lots of fds from lua-http, do we really want the
-housekeeping of making GLib.io_add_watch for each of them? it looks
-like adding a glib source from lgi is not currently practical
-https://github.com/lgi-devs/lgi/issues/111
-
-3) if we put http calls inside cq:wrap, that make them background
-provided that we call (cq:step 0)
-periodically. we could do that in a glib idle function, perhaps.
-
-- The tile fetcher would need to know where to write the data when
-  eventually it comes back
-- need some say to not fetch the same tile 18 times if there's more than
-  one request for it while a previous request is in progress
-
-
----- 
 
 https://git.syndicate-lang.org/tonyg/squeak-phone/raw/commit/474960ddc665ed445a1f5afb0164fe39057720f9/devices/pine64-pinephone/modem-docs/80545ST10798A_LM940_QMI_Command_Reference_Guide_r3.pdf
 
 ----
 
+... sod, forgot to push latest changes from noetbook
+
+we need to extend to multiple tiles'-worth of map
+
+* get tile for curent lat/long and request overpass data for enough
+  surrounding tiles to fill the screen
+
+* I think a way is served with all its nodes whether or not they're in
+the bbox, so we can just store the ids of ways we've seen and skip
+them if the come up again
+
+* render all the polylines into the widget (some day also the labels etc)
+
+* to get it centred on the cyclist, take the tile fractional part *
+  256, and translate the canvas up and left by that amount
 
 
 
+and offset
+by 
+
+