#summary Protocol for frontend/engine interaction.
#labels Documentation

= Introduction =

The frontend interacts with the engine in two separate occasions:
  * map preview generation;
  * game setup and statistics messages.

Messages are always in form of a string of bytes, and the first byte contains the message size (hence the maximum length is 255-1).

= Map Preview =
Frontend needs to generate a preview of the map that is going to be used in game; there is no handshaking.

Files on which this protocol is implemented: MapConfigViewController.m
== Protocol ==
|| *Frontend*      || *Engine*          || *Format*                  ||
|| UUID            ||                   || {{{eseed{ ... }}}}        ||
|| Template Filter ||                   || {{{e$template_filter N}}} ||
|| Map Type        ||                   || {{{e$mapgen N}}}          ||
|| Maze Value      ||                   || {{{e$maze N}}}            ||
||                 || 128x32 byte array || {{{0YSD3 ... FSAD0}}}     ||

=== UUID ===
The UUID is a 32 bytes array composed of ASCII characters; groups of letters should be separated by '-'.

Example: _eseed {AERTB-62FASDSAD-NNIASDSADASD-12P}_

=== Template Filter ===
_N_ selects the type of map that is going to be generated. This command is ignored when MapGen is not 0, but it must be set anyways.

|| *Value* || *Filter Selected* ||
|| 0       || None          ||
|| 1       || Large         ||
|| 2       || Medium        ||
|| 3       || Small         ||
|| 4       || Cavern        ||
|| 5       || Wacky         ||

Example: _e$template_filter 0_

=== Map Type ===
_N_ is a boolean variable (0/1) that selects standard map generation or maze map generation.

|| *Value* || *Map Type*   ||
|| 0       || Standard Map ||
|| 1       || Maze Map     ||

Example: _e$mapgen 1_

=== Maze Value ===
_N_ selects the type of maze selected, similarly to Template Filter

|| *Value* || *Filter Selected*       ||
|| 0       || Small Tunnels           ||
|| 1       || Medium Tunnels          ||
|| 2       || Large Tunnels           ||
|| 3       || Small Floating Islands  ||
|| 4       || Medium Floating Islands ||
|| 5       || Large Floating Islands  ||

Example: _e$mazesize 4_

= In-Game =