ScriptCraft

A Minecraft mod that lets you build using Javascript.

(Update 2013/01/04 - I've created a Bukkit Plugin as this makes installing the mod much easier - assuming you're running a CraftBukkit server - which I recommend. See Bukkit Support for details).

Description

The ScriptCraft mod lets you enter javascript commands at the in-game prompt. To bring up the in-game prompt press the / key then type js followed by any javascript statement. E.g. /js 1+1 will print 2. ScriptCraft uses Rhino (The built-in javascript interpreter that comes with current versions of Java).

As of Dec 27 2012, the ScriptCraft mod includes just a few built-in objects and functions to make building easier.

• echo( message ) - displays a message on the player's screen. e.g. /js echo( 1 + 3 ) or /js echo ("Hello World")
• getMousePos() - A function which returns the current position of the cross-hairs (if a block is targeted)
• getPlayerPos() - A function which returns the current position of the player.
• putBlock( x, y, z, blockId, metaData ) - A function which lets you place a block anywhere (if no coordinates are given the block the player is currently looking at is replaced).
• getBlock( x, y, z ) - returns the blockId and metadata at the given location (if no coordinates are given the cross-hair location is used)
• putSign( String[] texts, x, y, z, blockId, metaData ) - A function which lets you place a sign.

The above primitives can be used to create buildings which would otherwise be time-consuming to create manually. It is highly recommended using the attached drone javascript plugin which provides a fluent API for building. The Javascript Drone class provides a much richer API which can be used to construct buildings. See the attached cottage.js file for an example of you can use the sample Drone plugin to create new buildings in Minecraft.

Functions in MCP version of Scriptcraft (no longer supported).

• help() - Brings up a short help message.
• load('path-to-script.js') - lets you load and execute any javascript source file. In the context of script files, the __script variable will refer to the current script filename and __folder refers to the directory in which the current script resides. In the MCP (Minecraft Coder Pack) version of ScriptCraft, calling load() with no parameters will bring up a File Chooser dialog. This feature was removed from the multi-player bukkit version of ScriptCraft.

Prerequisites

(Minecraft Coder Pack Only - Bukkit users go here )

You will need to install Rhino (A javascript implementation for java) if it is not already installed. Type...

java org.mozilla.javascript.tools.shell.Main 

... at a command prompt to see if Rhino is already installed. If Rhino is installed you should see the following...

js> 

If Rhino is not already installed you can download it, unzip it and copy the js.jar file to ...

• Macintosh - /System/Library/Java/Extensions/
• Windows - C:\jdk\jre\lib\ext (assuming the Java Dev Kit has been installed in c:\jdk)
• Linux (Ubuntu) - /usr/lib/jvm/java-6-openjdk-i386/jre/lib/ext/ or /usr/lib/jvm/java-7-oracle/jre/lib/ext/ for Oracle Java

You will also need to install the Minecraft Coder Pack (CraftBukkit Users - please skip this section and go here instead) and be comfortable installing a Minecraft Mod. You can get the Minecraft Coder Pack here...

http://mcp.ocean-labs.de/index.php/Main_Page

... You will need to follow MCP's instructions to decompile your minecraft.jar file.

Installing

(Minecraft Coder Pack only - Bukkit users go here. )

Once you've installed Minecraft Coder Pack (MCP) and Rhino...

1. Copy the CommandScript.java file to the src/minecraft/net/minecraft/src/ located in the directory where you installed MCP.

2. Create a new directory called ScriptCraft on your C:\ drive (Windows) or your home directory (Linux/Max), and copy all of the .js files provided.

3. If you are on a Windows computer ...

   1. Launch Notepad (or your favourite text editor) and open file src/minecraft/net/minecraft/src/ServerCommandManager.java
   2. Insert a new line after this.registerCommand(new CommandTime());
   3. type this.registerCommand(new CommandScript());
   4. Save the file and close the editor.

4. If you are on a Linux or Mac OS X computer...

   1. Copy ServerCommandManager.patch to the directory where you installed MCP.
   2. Open a terminal window and cd to the directory where you installed MCP.
   3. enter the following command patch src/minecraft/net/minecraft/src/ServerCommandManager.java ServerCommandManager.patch

5. Open a Command Prompt (windows) or Terminal (Linux/Mac), go to the MCP directory and run recompile.bat (windows) or ./recompile.sh (Linux/Mac)

6. Run reobfuscate.bat (windows) or ./reobfuscate.sh (Linux/Mac).

7. Follow MCP's instructions for copying the obfuscated files and rebuilding the minecraft.jar file that is in %appdata%/minecraft/bin (windows), ~/Library/Application Support/Minecraft/bin (Mac) or ~/.minecraft/bin (Linux).

Getting Started

(Minecraft Coder pack version only - Bukkit users go here ) Once you've installed the mod, launch Minecraft and type /js load() and load the cottage.js file. Once the cottage.js file is loaded you can create a new cottage by typing /js cottage(). Take a look over the cottage.js file to see how the Drone module can be used to easily create buildings. You can even create a whole row of cottages using the following in-game command...

/js load("./cottage"); // path may vary on your machine
/js d = new Drone(); for (i=0; i < 20;i++){ cottage(d).right(10);}

The above code loads the example blueprint for a cottage and uses a for loop to create multiple cottages from the blueprint. Keep a Minecraft Block reference handy - there's one here ...

http://www.minecraftinfo.com/idlist.htm

Further Reading

You can find more information about ScriptCraft on my blog.