default setting

This setting specifies the default value for a parameter or a user function.

Parameters

If the type of the parameter is included in the parameter block, the default setting specifies only the default value. In this case, it can also be an expression that evaluates to the default value when the formula is compiled. The expression can only use constant values, including predefined symbols, but not including the values of other parameters.

If the type of the parameter is not included in the parameter block, the default setting is either a bool, int, float, or complex value and specifies the type and the default value of the parameter. The type of the parameter is set to the type of this setting. Therefore, you must be careful when specifying the default value. Suppose you want a float parameter with the default value 4. In this case you have to use the value 4.0 instead of 4; otherwise the type of the parameter would be int. If the default setting is not specified, the parameter is treated as complex, with a default value of (0, 0).

For readability, it is recommended to explicitly specify the type of a parameter before the parameter block.

Plug-in parameters

For plug-in parameters, the default setting is a class name that specifies the default plug-in to use for this parameter. The default plug-in should of course be derived from the parameter class. The class name is looked up in the list of imported classes. If omitted, the default plug-in is the same as the base class for the parameter.

User functions

The default setting is a function value and specifies the default value of the user function. It is important to add parentheses () after the function name. If this setting is not specified, the default value of the user function is set to sin() for complex user functions, or mergenormal() for color user functions.

General

This setting can only occur inside parameter blocks and function blocks.

Examples:

default:
  param FloatParam1
    default = 3.0  ; type implicitly set to float
  endparam
  float param FloatParam2
    default = 3
  endparam
  complex param CenterParam
    default = #center + (2, 0)
  endparam
  color param ColorParam
    default = rgb(1, 0, 0)
  endparam
  complex func MyFunc1
    default = sqr()
  endfunc
  color func MyFunc2
    default = mergesoftlight()
  endfunc
  MyClass param MyClassParam
    default = MyDerivedClass
  endparam