Enums

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Enum is a user defined datatype in HPL3. It is used to assign names to the integral constants which makes a script easy to read and maintain. The keyword enum is used to declare an enumeration.

Declaring Enum Variable

The general syntax for declaring an enumeration is

enum enum_name
{
   enumeration list 
}

Where:

  • enum_name specifies the enumeration type name.
  • enumeration list is a comma-separated list of identifiers.

Each of the symbols in the enumeration list stands for an integer value, one greater than the symbol that precedes it. By default, the value of the first enumeration symbol is 0. For example:

enum WeekDay
{
   Day_Sun, // The value here is 0
   Day_Mon, // The value here is 1
   Day_Tue, // etc
   Day_Wed,
   Day_Thu,
   Day_Fri,
   Day_Sat
}

Using Enums

The following example demonstrates use of enum variable:
enum WeekDay
{
   Day_Sun, // The value here is 0
   Day_Mon, // The value here is 1
   Day_Tue, // etc
   Day_Wed,
   Day_Thu,
   Day_Fri,
   Day_Sat
}

//--------------------------------------------------

class cScrMap : iScrMap
{
	////////////////////////////
	// Run first time starting map
	void OnStart()
	{
		WeekDay currentDay = Day_Mon;
		cLux_AddDebugMessage("The current day is: " + currentDay);
	}

When the above code is run, the number 1 will be printed to the screen, because the internal value of Day_Mon is 1.

In HPL3

Enums are mostly required as a parameter for existing HPL3 functions. One of the most common function which uses an enum is Music_Play. For example:
Music_Play("MyMusicFile.ogg", 1.0f, false, eMusicPrio_BgAmb);

The last parameter, eMusicPrio_BgAmb, is a value of the enum eMusicPrio.