Difference between revisions of "AGIWiki/Defines"

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'''Defines''', in [[AGIWiki/AGI|AGI]] [[AGIWiki/Logic|logic]], allow you to provide a proper name for the [[AGIWiki/Variable|variables]], [[AGIWiki/Flag|flags]], [[AGIWiki/Animated object|objects]] and other data in the game. This significantly improves the readability of the code.
 
'''Defines''', in [[AGIWiki/AGI|AGI]] [[AGIWiki/Logic|logic]], allow you to provide a proper name for the [[AGIWiki/Variable|variables]], [[AGIWiki/Flag|flags]], [[AGIWiki/Animated object|objects]] and other data in the game. This significantly improves the readability of the code.
  
To create a define name, use the <source lang="cpp">#define</source> command. The name of the define is given, followed by the define value:
+
To create a define name, use the <syntaxhighlight lang="cpp">#define</source> command. The name of the define is given, followed by the define value:
<source lang="cpp">
+
<syntaxhighlight lang="cpp">
 
  #define ego o0
 
  #define ego o0
 
  #define roomDescription "This is a large hall with tall pillars down each side."
 
  #define roomDescription "This is a large hall with tall pillars down each side."
Line 10: Line 10:
  
 
Then the define name can be used in place of the define value:
 
Then the define name can be used in place of the define value:
<source lang="cpp">
+
<syntaxhighlight lang="cpp">
 
  draw(ego);
 
  draw(ego);
 
  print(roomDescription);
 
  print(roomDescription);
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Below is a typical [[AGIWiki/New room section|new room section]] of a logic file, without defines:
 
Below is a typical [[AGIWiki/New room section|new room section]] of a logic file, without defines:
<source lang="cpp">
+
<syntaxhighlight lang="cpp">
 
  if (f5)
 
  if (f5)
 
  {
 
  {
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</source>
 
</source>
 
The same code, using defines, might appear like the following:
 
The same code, using defines, might appear like the following:
<source lang="cpp">
+
<syntaxhighlight lang="cpp">
 
  #define new_room f5
 
  #define new_room f5
 
  #define room_no  v0
 
  #define room_no  v0

Revision as of 15:12, 25 October 2018

AGIWiki


Defines, in AGI logic, allow you to provide a proper name for the variables, flags, objects and other data in the game. This significantly improves the readability of the code.

To create a define name, use the <syntaxhighlight lang="cpp">#define</source> command. The name of the define is given, followed by the define value: <syntaxhighlight lang="cpp">

#define ego o0
#define roomDescription "This is a large hall with tall pillars down each side."

</source>

Then the define name can be used in place of the define value: <syntaxhighlight lang="cpp">

draw(ego);
print(roomDescription);

</source> Note: The rules for defines vary depending on the compiler. The following discussion applies to the AGI Studio compiler.

Define names can only be used in arguments of commands (including gotos and the v0 == 3 type syntax (some compilers may allow you to use them anywhere).

Defines must be defined in the file before they are used.

The define name can contain letters, numbers, and the characters '_' and '.'. Spaces are not allowed.

Example

Below is a typical new room section of a logic file, without defines: <syntaxhighlight lang="cpp">

if (f5)
{
  load.pic(v0);
  draw.pic(v0);
  discard.pic(v0);
  draw(o0);
  show.pic();
}

</source> The same code, using defines, might appear like the following: <syntaxhighlight lang="cpp">

#define new_room f5
#define room_no  v0
#define ego      o0
if (new_room)
{
   load.pic(room_no);
   draw.pic(room_no);
   discard.pic(room_no);
   draw(ego);
   show.pic();
}

</source> The AGI Studio compiler allows you to place the #define commands in a separate file and then use those defines in multiple logics without having to redefine them all again. See includes for more details.

See also

Sources