Class Reference

The classes/objects of the HALion Script language are structured in the following class hierarchy.

HALion Script Class Hierarchy

• AudioFile
• Element
  • Bus
  • Effect
  • Instance
  • Layer
    • Program
  • MidiModule
  • ModulationMatrixRow
  • Slot
  • Zone
• Event
• LoadProgress
• ParameterDefinition

Classes deeper down inherit the data fields and methods of classes higher up in the class hierarchy. For example, the classes Bus, Instance, Layer, Effect, and so on, inherit all data fields and methods of the Element class. Subclasses add functionality to their parent class by providing more data fields and methods.

Addressing Objects

The Lua Script MIDI module itself can be addressed with this. Further objects can be addressed with this.parent, this.program or with the get/find functions.

After addressing an object, you can read its fields through dot-notation. In the following example, the name and the type of different objects are printed with .name and .type

Example 1

-- print the name and type of different objects
print(this.name, this.type)
print(this.parent.name, this.parent.type)
print(this.program.name, this.program.type)
print(this.program:getChild().name, this.program:getChild().type)

For more information on the available fields, see the description of the classes in the Class Reference.

Calling Methods

To operate on an element in the Program Tree, you must first adress its object and then call the desired method. The basic syntax is as follows:

Example 2

zone = this.parent:getZone() -- get the object of the first Zone after the script module
zone:setName("MyZone") -- setName operates on the Zone object

Using type() on Objects

For the HALion Script language the type() function of Lua has been extended to return the type of an object.

Example 3

-- print the name of all zones in the program
elements = this.program:findChildren(true)
for i, element in ipairs(elements) do
	if type(element) == "Zone" then
		print(element.name)
	end
end