Parameter-related classes and functions

The concept of parameter in the JeVois framework embodies wrappers around a single value of any type, with associated documentation (description), default values, possible specification of valid values, accessor functions to obtain or change the value, and optional callback functions that are triggered when the value is changed. Parameters are intended to be used in objects that inherit from Component. The goal of parameters is to expose parameters of a given vision algorithm in such a way that any piece of code that is using that algorithm will automatically inherit and expose these parameters.

How to explore this documentation module:

• Start with a bit of general philosophy about components and parameters: Component
• Then understand how one may specify valid values for parameters: Specification of sets of valid values, e.g., that some Parameter may take
• Then have a look at how one may define the name, type, description, default value, category, and optionally valid values for a parameter: ParameterDef<T>
• Then you are ready for Parameter

The other classes in this documentation module are mainly for support of the above ones.

Convenience macro to define a Parameter type

JEVOIS_DECLARE_PARAMETER(ParamName, ParamType, ...)

ParamName is the name chosen for the parameter. A new class type will be created with that name, so it must be syntactically correct as a class name. ParamType is the type of the parameter value. The remaining arguments are passed to the constructor of jevois::ParameterDef<T> with T=ParamType.

Convenience macro to define a Parameter type, with callback

JEVOIS_DECLARE_PARAMETER_WITH_CALLBACK(ParamName, ParamType, ...)

ParamName is the name chosen for the parameter. A new class type will be created with that name, so it must be syntactically correct as a class name. ParamType is the type of the parameter value. The remaining arguments are passed to the constructor of jevois::ParameterDef<T> with T=ParamType.

In this version with callback, a pure virtual method is included in the new class that is defined, with the following signature:

virtual void onParamChange(ParamName const & param, ParamType const & newval) = 0;

The host class (typically, a Component) that inherits from Parameter<ParamName> must implement an override of this function. A compile-time error will be issued if that override has not been implemented.

Collaboration diagram for Parameter-related classes and functions:

Classes
class	jevois::ParameterSummary
	ParameterSummary provides a summary about a parameter. More...
class	jevois::ParameterBase
	Base class for Parameter. More...
class	jevois::ParameterCore< T >
	A changeable parameter for a Component, core class. More...
class	jevois::Parameter< Param, Tail ... >
	A set of Parameters attached to a component. More...
class	jevois::DynamicParameter< T >
	Dynamic parameter added to a component at runtime. More...
struct	jevois::ParameterCategory
	A category to which multiple ParameterDef definitions can belong. More...
class	jevois::ParameterDefBase
	Base class for a Parameter definition. More...
class	jevois::ParameterDef< T >
	A Parameter Definition. More...
class	jevois::ParameterRegistry
	A simple registry of all parameters associated with a Component. More...

Modules
	String conversions for Parameter
	Specification of sets of valid values, e.g., that some Parameter may take