Getting Started

From COD Modding & Mapping Wiki
Revision as of 02:35, 24 October 2008 by Novemberdobby (talk | contribs)
Jump to navigation Jump to search

Getting Started

This section will include several things you need to know before you start scripting.

All scripts are contained within simple text files that contain no formatting, so programs such as Word are not to be used. The file format used for scripts within the Call of Duty series is 'GSC' (.gsc). It is recommended you use a simple but effective editor for programming, such programs include Crimson Editor, Programmers Notepad and Editplus.

A few things you need to know before reading any further are a few common words used within scripting.

Variables: variables are data storage locations which are assigned a name. For example...

 integerthing = 1; //by the way, comments like this can be made using //, and are ignored by the game.
 floatthing = 0.5; 
 stringthing = "Text and symbols 1234567890";
 booleanthing = true; //another thing, almost every line must have a ; at the end or the script won't work. More on that later.

The variables are declared on the left, and assigned a value such as an integer (whole number), a float (a number containing a decimal), a string (text and symbols) or a boolean (true/false).

Entities: These are objects that are used in maps, and can be referenced in the script. Entities include players, dropped guns, objectives, script_models, etc.

They can be referenced using their their targetname or classname that has been set within the map.

Functions: an action or procedure that can be called or threaded and can return a value. For example...

 funcMove()
 {
   self moveY(320, 3);
 }

The main function in the above code is funcMove(), and it will perform the actions inside the curly braces when it runs. There is also another function, moveY, which is a built-in function inside COD4, and moves an entity on the Y axis.

Arguements: These are key piece of information that are passed along to functions, and can be any type of object (entity, string, boolean etc). The function that was passed the arguments can then reference them.

For example, if a function is shown as

 function(arg1, arg2)

The function is asking for two arguements to be sent to the function. An example of this in use...

 someotherstuff()
 {
   ent function(320, 5);
   thing function(320, 5);
 }

 function(distance, time)
 {
   ent moveZ(distance, time);
 }

As you can see, function() is called on both 'ent' and 'thing', and the two arguments '320' and '5' are passed to the new function as 'distance' and 'time'. Then moveZ is called on the entities.

Calling/Threading: these are used with functions. Functions can be threaded or called sequentially.

If a function is threaded, then that function is performed while the script continues, whereas if a function is called sequentially, the script waits until the function is completed before it continues. Examples...

 function(); //the script will stop at this line and carry out function() before going down to...
 thread function(); //this will start function() and carry on to execute 'ent moveZ'
 ent moveZ(350, 5);

Self: If you call a function on an entity e.g 'unnamedent thread dostuff()', then within the function dostuff(), you can refer to unnamedent as 'self'.

For example...

 something()
 {
  ent = getent("ent","targetname");
  ent function();
 }

 function()
 {
  self moveZ(150, 5);
 }