merged 3.3 and 3.5
This commit is contained in:
Jeena Paradies
parent
452f213c02
commit
467f4d729b
1 changed files with 209 additions and 623 deletions
832
report.lyx
832
report.lyx
|
|
@ -460,7 +460,7 @@ Due to the increasing importance of computer gaming, more focus should be
|
||||||
\end_layout
|
\end_layout
|
||||||
|
|
||||||
\begin_layout Standard
|
\begin_layout Standard
|
||||||
The reliable generic game server, hereafter known as GGS
|
The Reliable Generic Game Server, hereafter known as the GGS
|
||||||
\begin_inset ERT
|
\begin_inset ERT
|
||||||
status open
|
status open
|
||||||
|
|
||||||
|
|
@ -2391,11 +2391,11 @@ n between server and client.
|
||||||
The GGS protocol is described in more detail in section
|
The GGS protocol is described in more detail in section
|
||||||
\begin_inset CommandInset ref
|
\begin_inset CommandInset ref
|
||||||
LatexCommand ref
|
LatexCommand ref
|
||||||
reference "sub:The-structure-of"
|
reference "sub:The-protocol-parser"
|
||||||
|
|
||||||
\end_inset
|
\end_inset
|
||||||
|
|
||||||
|
.
|
||||||
\end_layout
|
\end_layout
|
||||||
|
|
||||||
\begin_layout Section
|
\begin_layout Section
|
||||||
|
|
@ -4283,624 +4283,6 @@ tt
|
||||||
.
|
.
|
||||||
\end_layout
|
\end_layout
|
||||||
|
|
||||||
\begin_layout Section
|
|
||||||
Communication with external systems and applications
|
|
||||||
\begin_inset CommandInset label
|
|
||||||
LatexCommand label
|
|
||||||
name "sec:Communication-with-external"
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Standard
|
|
||||||
A game launched on the GGS is run within a virtual machine.
|
|
||||||
For each programming language supported, there is a virtual machine that
|
|
||||||
interprets the game.
|
|
||||||
Furthermore an interface for communication between the GGS, the game and
|
|
||||||
the players playing the game must be present.
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Standard
|
|
||||||
The reason for the GGS requiring a communication channel between the game
|
|
||||||
VM and Erlang is in part because the GGS makes heavy use of callbacks.
|
|
||||||
Callbacks written in Erlang are registered to the VM for the interface
|
|
||||||
to work.
|
|
||||||
It is only with the help of the interface that the game developer can access
|
|
||||||
the game state and send messages between players.
|
|
||||||
The interface provides access to three objects called
|
|
||||||
\emph on
|
|
||||||
world
|
|
||||||
\emph default
|
|
||||||
,
|
|
||||||
\emph on
|
|
||||||
player
|
|
||||||
\emph default
|
|
||||||
and
|
|
||||||
\emph on
|
|
||||||
localstorage
|
|
||||||
\emph default
|
|
||||||
.
|
|
||||||
The game state is safely stored in a database and retrieved for manipulation
|
|
||||||
by a call for the world object.
|
|
||||||
Interaction with the players is done the same way using the player object
|
|
||||||
instead.
|
|
||||||
The localstorage is a convenient way to store global data and other data
|
|
||||||
separated from the game state.
|
|
||||||
In section
|
|
||||||
\begin_inset CommandInset ref
|
|
||||||
LatexCommand ref
|
|
||||||
reference "sub:Exposing-Erlang-functionality"
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
a concrete example of the implementation of the localstorage and world
|
|
||||||
objects is given.
|
|
||||||
\begin_inset Note Note
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
Unique id:s called gametokens are generated for hosted games so that they
|
|
||||||
are not mixed up.
|
|
||||||
-- good text, integrate more.
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
|
|
||||||
\begin_inset ERT
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
|
|
||||||
\backslash
|
|
||||||
nomenclature{
|
|
||||||
\backslash
|
|
||||||
textbf{WebStorage}}{A new standard for letting websites store data on visitors'
|
|
||||||
computers}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Subsection
|
|
||||||
Exposing Erlang functionality to the GDL VM
|
|
||||||
\begin_inset CommandInset label
|
|
||||||
LatexCommand label
|
|
||||||
name "sub:Exposing-Erlang-functionality"
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Standard
|
|
||||||
This section contains a concrete example of how the localstorage and world
|
|
||||||
objects are exposed to a GDL VM.
|
|
||||||
The example comes from the GGS prototype, which uses JavaScript powered
|
|
||||||
by Google V8 as its GDL VM.
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Standard
|
|
||||||
The code given in
|
|
||||||
\begin_inset CommandInset ref
|
|
||||||
LatexCommand ref
|
|
||||||
reference "alg:exposing-erlang"
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
is specific to V8 and JavaScript, however implementations for different
|
|
||||||
GDLs, or different JavaScript VMs should be similar.
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Standard
|
|
||||||
In JavaScript is is common to use a top level object, called a global object,
|
|
||||||
to establish a global scope.
|
|
||||||
This allows declaration of global variables and functions.
|
|
||||||
To gain access to the global object in the GGS, the
|
|
||||||
\begin_inset ERT
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{
|
|
||||||
\backslash
|
|
||||||
tt erlv8
|
|
||||||
\backslash
|
|
||||||
_vm:global(..)}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
function on line 2 of the example is used.
|
|
||||||
Using the global object, declarations of the world and GGS object can be
|
|
||||||
placed in the global scope.
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Standard
|
|
||||||
\begin_inset ERT
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{
|
|
||||||
\backslash
|
|
||||||
tt Global:set
|
|
||||||
\backslash
|
|
||||||
_value(..)}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
is a call to the global object, declaring new objects in the global scope.
|
|
||||||
On line 4 the GGS object is declared.
|
|
||||||
By accessing
|
|
||||||
\begin_inset ERT
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{
|
|
||||||
\backslash
|
|
||||||
tt GGS.localStorage }
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
from within the GDL, access to the localstorage is provided, thus the localstor
|
|
||||||
age must be connected to the GGS object, this can be seen in line 5.
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Standard
|
|
||||||
Both the GGS and localstorage objects are dummy objects, which provide no
|
|
||||||
functionality, these two objects are simply placed in the GDL for the purpose
|
|
||||||
clearing up the code.
|
|
||||||
In order to perform an action using the GGS and localstorage objects, the
|
|
||||||
|
|
||||||
\begin_inset ERT
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{
|
|
||||||
\backslash
|
|
||||||
tt getItem} and {
|
|
||||||
\backslash
|
|
||||||
tt setItem}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
functions must be used.
|
|
||||||
These items are directly connected to the database module of the GGS, which
|
|
||||||
is discussed in more detail in
|
|
||||||
\begin_inset CommandInset ref
|
|
||||||
LatexCommand ref
|
|
||||||
reference "sub:The-database-module"
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
.
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Standard
|
|
||||||
Similarly the functions
|
|
||||||
\begin_inset ERT
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{
|
|
||||||
\backslash
|
|
||||||
tt sendCommand, sendCommandToAll} and {
|
|
||||||
\backslash
|
|
||||||
tt setTimeout}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
are directly connected to a piece of code in the GGS which performs the
|
|
||||||
desired action.
|
|
||||||
The
|
|
||||||
\begin_inset ERT
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{
|
|
||||||
\backslash
|
|
||||||
tt sendCommand}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
functions are used to send commands or text to participants of the table.
|
|
||||||
The
|
|
||||||
\begin_inset ERT
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{
|
|
||||||
\backslash
|
|
||||||
tt setTimeout}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
function introduces timeouts to the V8 engine, which are not available
|
|
||||||
per default.
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Standard
|
|
||||||
\begin_inset Float algorithm
|
|
||||||
wide false
|
|
||||||
sideways false
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
\begin_inset ERT
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
|
|
||||||
\backslash
|
|
||||||
lstset{
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
language=Erlang,
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
backgroundcolor=
|
|
||||||
\backslash
|
|
||||||
color{white},
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
extendedchars=true,
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
basicstyle=
|
|
||||||
\backslash
|
|
||||||
footnotesize
|
|
||||||
\backslash
|
|
||||||
ttfamily,
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
showstringspaces=false,
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
showspaces=false,
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
numbers=left,
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
numberstyle=
|
|
||||||
\backslash
|
|
||||||
footnotesize,
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
numbersep=9pt,
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
tabsize=2,
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
breaklines=true,
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
showtabs=false,
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
captionpos=b
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
|
|
||||||
\backslash
|
|
||||||
begin{lstlisting}[language=Erlang]
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
% @doc Exposes some GGS functions to JavaScript
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
expose(GameVM, Table) ->
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
Global = erlv8_vm:global(GameVM),
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
Global:set_value("GGS", erlv8_object:new([
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{"localStorage", erlv8_object:new([
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{"setItem", fun(#erlv8_fun_invocation{}, [Key, Val])->
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
ggs_db:setItem(Table, local_storage, Key, Val)
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
end},
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{"getItem", fun(#erlv8_fun_invocation{}, [Key])->
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
ggs_db:getItem(Table, local_storage, Key)
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
end}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
% more functions ...
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
])},
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{"world", erlv8_object:new([
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{"setItem", fun(#erlv8_fun_invocation{}, [Key, Val])->
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
ggs_db:setItem(Table, world, Key, Val),
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
ggs_table:send_command_to_all(
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
Table, {"world_set", Key ++ "=" ++ Val}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
)
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
end},
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{"getItem", fun(#erlv8_fun_invocation{}, [Key])->
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
ggs_db:getItem(Table, world, Key),
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
end}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
% more functions ...
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
])},
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{"sendCommand", fun(#erlv8_fun_invocation{}, [Player, Command, Args])->
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
ggs_table:send_command(Table, Player, {Command, Args})
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
end},
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{"sendCommandToAll", fun(#erlv8_fun_invocation{}, [Command, Args])->
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
ggs_table:send_command_to_all(Table, {Command, Args})
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
end}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
{"setTimeout", fund(#erlv8_fun_invocation{}, [Time, Function])->
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
timer:apply_after(Time, ?MODULE, call_js, [GameVM, Function])
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
end}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
% more functions ...
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
])).
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
|
|
||||||
|
|
||||||
\backslash
|
|
||||||
end{lstlisting}
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
\begin_inset Caption
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
\begin_inset CommandInset label
|
|
||||||
LatexCommand label
|
|
||||||
name "alg:exposing-erlang"
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
An example of how Erlang functionality is exposed to a Javascript GDL
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Standard
|
|
||||||
\begin_inset Note Note
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
TODO: Go in to more detail about how the world, player and localstorage
|
|
||||||
objects are implemented.
|
|
||||||
Also discuss localstorage and how it derives from the webstorage standard
|
|
||||||
in detail.
|
|
||||||
This is a great point on how we try to follow standards.
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Standard
|
|
||||||
\begin_inset Note Note
|
|
||||||
status open
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
My idea here is that we describe the erlang-js (which failed, but nonetheless),
|
|
||||||
v8, UUID and other external communication.
|
|
||||||
We shouldn't describe sockets here though..
|
|
||||||
or..
|
|
||||||
maybe?
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
|
||||||
Also discuss how we allow GDLs to communicate with Erlang, this is
|
|
||||||
\begin_inset Quotes eld
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
external
|
|
||||||
\begin_inset Quotes erd
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
to three GDL.
|
|
||||||
Discuss the GGS world object (there is a reference to this section for
|
|
||||||
that purpose)
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\end_inset
|
|
||||||
|
|
||||||
|
|
||||||
\end_layout
|
|
||||||
|
|
||||||
\begin_layout Section
|
\begin_layout Section
|
||||||
The modular structure of the GGS prototype
|
The modular structure of the GGS prototype
|
||||||
\begin_inset CommandInset label
|
\begin_inset CommandInset label
|
||||||
|
|
@ -5784,8 +5166,212 @@ sendCommandToAll(command, args).
|
||||||
are not mixed up.
|
are not mixed up.
|
||||||
\end_layout
|
\end_layout
|
||||||
|
|
||||||
|
\begin_layout Standard
|
||||||
|
A game launched on the GGS is run within a virtual machine.
|
||||||
|
For each programming language supported, there is a virtual machine that
|
||||||
|
interprets the game.
|
||||||
|
Furthermore an interface for communication between the GGS, the game and
|
||||||
|
the players playing the game must be present.
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\begin_layout Standard
|
||||||
|
\begin_inset Note Note
|
||||||
|
status open
|
||||||
|
|
||||||
|
\begin_layout Plain Layout
|
||||||
|
Unique id:s called gametokens are generated for hosted games so that they
|
||||||
|
are not mixed up.
|
||||||
|
-- good text, integrate more.
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\end_inset
|
||||||
|
|
||||||
|
|
||||||
|
\begin_inset ERT
|
||||||
|
status open
|
||||||
|
|
||||||
|
\begin_layout Plain Layout
|
||||||
|
|
||||||
|
|
||||||
|
\backslash
|
||||||
|
nomenclature{
|
||||||
|
\backslash
|
||||||
|
textbf{WebStorage}}{A new standard for letting websites store data on visitors'
|
||||||
|
computers}
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\end_inset
|
||||||
|
|
||||||
|
|
||||||
|
\end_layout
|
||||||
|
|
||||||
\begin_layout Subsection
|
\begin_layout Subsection
|
||||||
Exposing Erlang functionality to the GDL VM
|
Exposing Erlang functionality to the GDL VM
|
||||||
|
\begin_inset CommandInset label
|
||||||
|
LatexCommand label
|
||||||
|
name "sub:Exposing-Erlang-functionality"
|
||||||
|
|
||||||
|
\end_inset
|
||||||
|
|
||||||
|
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\begin_layout Standard
|
||||||
|
This section contains a concrete example of how the localstorage and world
|
||||||
|
objects are exposed to a GDL VM.
|
||||||
|
The example comes from the GGS prototype, which uses JavaScript powered
|
||||||
|
by Google V8 as its GDL VM.
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\begin_layout Standard
|
||||||
|
The code given in
|
||||||
|
\begin_inset CommandInset ref
|
||||||
|
LatexCommand ref
|
||||||
|
reference "alg:exposing-erlang"
|
||||||
|
|
||||||
|
\end_inset
|
||||||
|
|
||||||
|
is specific to V8 and JavaScript, however implementations for different
|
||||||
|
GDLs, or different VMs should be similar.
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\begin_layout Standard
|
||||||
|
In JavaScript is is common to use a top level object, called a global object,
|
||||||
|
to establish a global scope.
|
||||||
|
This allows the declaration of global variables and functions.
|
||||||
|
To gain access to the global object in the GGS, the
|
||||||
|
\begin_inset ERT
|
||||||
|
status open
|
||||||
|
|
||||||
|
\begin_layout Plain Layout
|
||||||
|
|
||||||
|
{
|
||||||
|
\backslash
|
||||||
|
tt erlv8
|
||||||
|
\backslash
|
||||||
|
_vm:global(..)}
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\end_inset
|
||||||
|
|
||||||
|
function on line 2 of the example is used.
|
||||||
|
Using the global object, declarations of the world and GGS object can be
|
||||||
|
placed in the global scope.
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\begin_layout Standard
|
||||||
|
\begin_inset ERT
|
||||||
|
status open
|
||||||
|
|
||||||
|
\begin_layout Plain Layout
|
||||||
|
|
||||||
|
{
|
||||||
|
\backslash
|
||||||
|
tt Global:set
|
||||||
|
\backslash
|
||||||
|
_value(..)}
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\end_inset
|
||||||
|
|
||||||
|
is a call to the global object, declaring new objects in the global scope.
|
||||||
|
On line 4 the GGS object is declared.
|
||||||
|
By accessing
|
||||||
|
\begin_inset ERT
|
||||||
|
status open
|
||||||
|
|
||||||
|
\begin_layout Plain Layout
|
||||||
|
|
||||||
|
{
|
||||||
|
\backslash
|
||||||
|
tt GGS.localStorage }
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\end_inset
|
||||||
|
|
||||||
|
from within the GDL, access to the localstorage is provided, thus the localstor
|
||||||
|
age must be connected to the GGS object, this can be seen in line 5.
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\begin_layout Standard
|
||||||
|
Both the GGS and localstorage objects are dummy objects, which provide no
|
||||||
|
functionality, these two objects are simply placed in the GDL for the purpose
|
||||||
|
clearing up the code.
|
||||||
|
In order to perform an action using the GGS and localstorage objects, the
|
||||||
|
|
||||||
|
\begin_inset ERT
|
||||||
|
status open
|
||||||
|
|
||||||
|
\begin_layout Plain Layout
|
||||||
|
|
||||||
|
{
|
||||||
|
\backslash
|
||||||
|
tt getItem} and {
|
||||||
|
\backslash
|
||||||
|
tt setItem}
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\end_inset
|
||||||
|
|
||||||
|
functions must be used.
|
||||||
|
These items are directly connected to the database module of the GGS, which
|
||||||
|
is discussed in more detail in
|
||||||
|
\begin_inset CommandInset ref
|
||||||
|
LatexCommand ref
|
||||||
|
reference "sub:The-database-module"
|
||||||
|
|
||||||
|
\end_inset
|
||||||
|
|
||||||
|
.
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\begin_layout Standard
|
||||||
|
Similarly the functions
|
||||||
|
\begin_inset ERT
|
||||||
|
status open
|
||||||
|
|
||||||
|
\begin_layout Plain Layout
|
||||||
|
|
||||||
|
{
|
||||||
|
\backslash
|
||||||
|
tt sendCommand, sendCommandToAll} and {
|
||||||
|
\backslash
|
||||||
|
tt setTimeout}
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\end_inset
|
||||||
|
|
||||||
|
are directly connected to a piece of code in the GGS which performs the
|
||||||
|
desired action.
|
||||||
|
The
|
||||||
|
\begin_inset ERT
|
||||||
|
status open
|
||||||
|
|
||||||
|
\begin_layout Plain Layout
|
||||||
|
|
||||||
|
{
|
||||||
|
\backslash
|
||||||
|
tt sendCommand}
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\end_inset
|
||||||
|
|
||||||
|
functions are used to send commands or text to participants of the table.
|
||||||
|
The
|
||||||
|
\begin_inset ERT
|
||||||
|
status open
|
||||||
|
|
||||||
|
\begin_layout Plain Layout
|
||||||
|
|
||||||
|
{
|
||||||
|
\backslash
|
||||||
|
tt setTimeout}
|
||||||
|
\end_layout
|
||||||
|
|
||||||
|
\end_inset
|
||||||
|
|
||||||
|
function introduces timeouts to the V8 engine, which are not available
|
||||||
|
per default.
|
||||||
\end_layout
|
\end_layout
|
||||||
|
|
||||||
\begin_layout Standard
|
\begin_layout Standard
|
||||||
|
|
@ -5806,7 +5392,7 @@ Prior to this section, the Erlang syntax has to be briefly explained.
|
||||||
\begin_inset Float algorithm
|
\begin_inset Float algorithm
|
||||||
wide false
|
wide false
|
||||||
sideways false
|
sideways false
|
||||||
status collapsed
|
status open
|
||||||
|
|
||||||
\begin_layout Plain Layout
|
\begin_layout Plain Layout
|
||||||
\begin_inset ERT
|
\begin_inset ERT
|
||||||
|
|
|
||||||
Loading…
Add table
Add a link
Reference in a new issue