docs/notes

   1 Some implementation notes:
   2
   3 There is an included flash object (web-socket-js) that is used to
   4 emulate websocket support on browsers without websocket support
   5 (currently only Chrome has WebSocket support).
   6
   7 The performance on Chrome is great. It only takes about 150ms on my
   8 system to render a complete 800x600 hextile frame. Most updates are
   9 partial or use copyrect which is much faster.
  10
  11 When using the flash websocket emulator, packets event aren't always
  12 delivered in order. This may be a bug in the way I'm using the
  13 FABridge interface. Or a bug in FABridge itself, or just a browser
  14 event delivery issue. Anyways, to get around this problem, when the
  15 flash emulator is being used, the client issues the WebSocket GET
  16 request with the "seq_num" variable. This switches on in-band sequence
  17 numbering of the packets in the proxy, and the client has a queue of
  18 out-of-order packets (20 deep currently) that it uses to re-order.
  19 Gross!
  20
  21 The performance on firefox 3.5 is usable. It takes 2.3 seconds to
  22 render a 800x600 hextile frame on my system (the initial connect).
  23 Once the initial first update is done though, it's quite usable (as
  24 above, most updates are partial or copyrect). I haven't tested firefox
  25 3.7 yet, it might be a lot faster.
  26
  27 Opera sucks big time. The flash websocket emulator fails to deliver as
  28 many as 40% of packet events when used on Opera. It may or not be
  29 Opera's fault, but something goes badly wrong at the FABridge
  30 boundary.
  31
  32 Javascript doesn't have a bytearray type, so what you get out of
  33 a WebSocket object is just Javascript strings. I believe that
  34 Javascript has UTF-16 unicode strings and anything sent through the
  35 WebSocket gets converted to UTF-8 and vice-versa. So, one additional
  36 (and necessary) function of the proxy is base64 encoding/decoding what
  37 is sent to/from the browser. Another option that I want to explore is
  38 UTF-8 encoding in the proxy.