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
830
report.lyx
830
report.lyx
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@ -460,7 +460,7 @@ Due to the increasing importance of computer gaming, more focus should be
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\end_layout
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\end_layout
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\begin_layout Standard
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\begin_layout Standard
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The reliable generic game server, hereafter known as GGS
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The Reliable Generic Game Server, hereafter known as the GGS
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\begin_inset ERT
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\begin_inset ERT
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status open
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status open
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@ -2391,11 +2391,11 @@ n between server and client.
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The GGS protocol is described in more detail in section
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The GGS protocol is described in more detail in section
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\begin_inset CommandInset ref
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\begin_inset CommandInset ref
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LatexCommand ref
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LatexCommand ref
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reference "sub:The-structure-of"
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reference "sub:The-protocol-parser"
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\end_inset
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\end_inset
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.
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\end_layout
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\end_layout
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\begin_layout Section
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\begin_layout Section
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@ -4283,624 +4283,6 @@ tt
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.
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.
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\end_layout
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\end_layout
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\begin_layout Section
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Communication with external systems and applications
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\begin_inset CommandInset label
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LatexCommand label
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name "sec:Communication-with-external"
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\end_inset
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\end_layout
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\begin_layout Standard
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A game launched on the GGS is run within a virtual machine.
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For each programming language supported, there is a virtual machine that
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interprets the game.
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Furthermore an interface for communication between the GGS, the game and
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the players playing the game must be present.
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\end_layout
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\begin_layout Standard
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The reason for the GGS requiring a communication channel between the game
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VM and Erlang is in part because the GGS makes heavy use of callbacks.
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Callbacks written in Erlang are registered to the VM for the interface
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to work.
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It is only with the help of the interface that the game developer can access
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the game state and send messages between players.
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The interface provides access to three objects called
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\emph on
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world
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\emph default
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,
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\emph on
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player
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\emph default
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and
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\emph on
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localstorage
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\emph default
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.
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The game state is safely stored in a database and retrieved for manipulation
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by a call for the world object.
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Interaction with the players is done the same way using the player object
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instead.
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The localstorage is a convenient way to store global data and other data
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separated from the game state.
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In section
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\begin_inset CommandInset ref
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LatexCommand ref
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reference "sub:Exposing-Erlang-functionality"
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\end_inset
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a concrete example of the implementation of the localstorage and world
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objects is given.
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\begin_inset Note Note
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status open
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\begin_layout Plain Layout
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Unique id:s called gametokens are generated for hosted games so that they
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are not mixed up.
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-- good text, integrate more.
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\end_layout
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\end_inset
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\begin_inset ERT
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status open
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\begin_layout Plain Layout
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\backslash
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nomenclature{
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\backslash
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textbf{WebStorage}}{A new standard for letting websites store data on visitors'
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computers}
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\end_layout
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\end_inset
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\end_layout
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\begin_layout Subsection
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Exposing Erlang functionality to the GDL VM
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\begin_inset CommandInset label
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LatexCommand label
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name "sub:Exposing-Erlang-functionality"
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\end_inset
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\end_layout
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\begin_layout Standard
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This section contains a concrete example of how the localstorage and world
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objects are exposed to a GDL VM.
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The example comes from the GGS prototype, which uses JavaScript powered
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by Google V8 as its GDL VM.
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\end_layout
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\begin_layout Standard
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The code given in
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\begin_inset CommandInset ref
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LatexCommand ref
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reference "alg:exposing-erlang"
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\end_inset
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is specific to V8 and JavaScript, however implementations for different
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GDLs, or different JavaScript VMs should be similar.
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\end_layout
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\begin_layout Standard
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In JavaScript is is common to use a top level object, called a global object,
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to establish a global scope.
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This allows declaration of global variables and functions.
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To gain access to the global object in the GGS, the
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\begin_inset ERT
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status open
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\begin_layout Plain Layout
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{
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\backslash
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tt erlv8
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\backslash
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_vm:global(..)}
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\end_layout
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\end_inset
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function on line 2 of the example is used.
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Using the global object, declarations of the world and GGS object can be
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placed in the global scope.
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\end_layout
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\begin_layout Standard
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\begin_inset ERT
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status open
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\begin_layout Plain Layout
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{
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\backslash
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tt Global:set
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\backslash
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_value(..)}
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\end_layout
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\end_inset
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is a call to the global object, declaring new objects in the global scope.
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On line 4 the GGS object is declared.
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By accessing
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\begin_inset ERT
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status open
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\begin_layout Plain Layout
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{
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\backslash
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tt GGS.localStorage }
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\end_layout
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\end_inset
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from within the GDL, access to the localstorage is provided, thus the localstor
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age must be connected to the GGS object, this can be seen in line 5.
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\end_layout
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\begin_layout Standard
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Both the GGS and localstorage objects are dummy objects, which provide no
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functionality, these two objects are simply placed in the GDL for the purpose
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clearing up the code.
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In order to perform an action using the GGS and localstorage objects, the
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\begin_inset ERT
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status open
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\begin_layout Plain Layout
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{
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\backslash
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tt getItem} and {
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\backslash
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tt setItem}
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\end_layout
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\end_inset
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functions must be used.
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These items are directly connected to the database module of the GGS, which
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is discussed in more detail in
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\begin_inset CommandInset ref
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LatexCommand ref
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reference "sub:The-database-module"
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\end_inset
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.
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\end_layout
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\begin_layout Standard
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Similarly the functions
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\begin_inset ERT
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status open
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\begin_layout Plain Layout
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{
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\backslash
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tt sendCommand, sendCommandToAll} and {
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\backslash
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tt setTimeout}
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\end_layout
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\end_inset
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are directly connected to a piece of code in the GGS which performs the
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desired action.
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The
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\begin_inset ERT
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status open
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\begin_layout Plain Layout
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{
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\backslash
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tt sendCommand}
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\end_layout
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\end_inset
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functions are used to send commands or text to participants of the table.
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The
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\begin_inset ERT
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status open
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\begin_layout Plain Layout
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{
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\backslash
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tt setTimeout}
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\end_layout
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\end_inset
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function introduces timeouts to the V8 engine, which are not available
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per default.
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\end_layout
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\begin_layout Standard
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\begin_inset Float algorithm
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wide false
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sideways false
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status open
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\begin_layout Plain Layout
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\begin_inset ERT
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status open
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\begin_layout Plain Layout
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\backslash
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lstset{
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\end_layout
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\begin_layout Plain Layout
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language=Erlang,
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\end_layout
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\begin_layout Plain Layout
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backgroundcolor=
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\backslash
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color{white},
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\end_layout
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\begin_layout Plain Layout
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extendedchars=true,
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\end_layout
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\begin_layout Plain Layout
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basicstyle=
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\backslash
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footnotesize
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\backslash
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ttfamily,
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\end_layout
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\begin_layout Plain Layout
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showstringspaces=false,
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\end_layout
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\begin_layout Plain Layout
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showspaces=false,
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\end_layout
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\begin_layout Plain Layout
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numbers=left,
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\end_layout
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\begin_layout Plain Layout
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numberstyle=
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\backslash
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footnotesize,
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\end_layout
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\begin_layout Plain Layout
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numbersep=9pt,
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\end_layout
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\begin_layout Plain Layout
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tabsize=2,
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\end_layout
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\begin_layout Plain Layout
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breaklines=true,
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\end_layout
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\begin_layout Plain Layout
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showtabs=false,
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\end_layout
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\begin_layout Plain Layout
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captionpos=b
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\end_layout
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\begin_layout Plain Layout
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}
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\end_layout
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\begin_layout Plain Layout
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\backslash
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begin{lstlisting}[language=Erlang]
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\end_layout
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\begin_layout Plain Layout
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% @doc Exposes some GGS functions to JavaScript
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\end_layout
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\begin_layout Plain Layout
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expose(GameVM, Table) ->
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\end_layout
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\begin_layout Plain Layout
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Global = erlv8_vm:global(GameVM),
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\end_layout
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\begin_layout Plain Layout
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Global:set_value("GGS", erlv8_object:new([
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\end_layout
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\begin_layout Plain Layout
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{"localStorage", erlv8_object:new([
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\end_layout
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\begin_layout Plain Layout
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{"setItem", fun(#erlv8_fun_invocation{}, [Key, Val])->
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\end_layout
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\begin_layout Plain Layout
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ggs_db:setItem(Table, local_storage, Key, Val)
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\end_layout
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\begin_layout Plain Layout
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end},
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\end_layout
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\begin_layout Plain Layout
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{"getItem", fun(#erlv8_fun_invocation{}, [Key])->
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\end_layout
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\begin_layout Plain Layout
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ggs_db:getItem(Table, local_storage, Key)
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\end_layout
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\begin_layout Plain Layout
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end}
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\end_layout
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\begin_layout Plain Layout
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% more functions ...
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\end_layout
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\begin_layout Plain Layout
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])},
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\end_layout
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\begin_layout Plain Layout
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{"world", erlv8_object:new([
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\end_layout
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\begin_layout Plain Layout
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{"setItem", fun(#erlv8_fun_invocation{}, [Key, Val])->
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\end_layout
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\begin_layout Plain Layout
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ggs_db:setItem(Table, world, Key, Val),
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\end_layout
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\begin_layout Plain Layout
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ggs_table:send_command_to_all(
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\end_layout
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\begin_layout Plain Layout
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Table, {"world_set", Key ++ "=" ++ Val}
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\end_layout
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\begin_layout Plain Layout
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)
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\end_layout
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\begin_layout Plain Layout
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end},
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\end_layout
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\begin_layout Plain Layout
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|
||||||
{"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