Parameter Files

To represent a node, you need its name and its type.

So the following example shows a valid parameter file:

minimal graph example

parameter	value	remarks
obj1.type	filereader	name: obj1; type: filereader

This results in the following graph structure:

minimal graph example visualization

Example file: minimal.wrp

Required parameters

As shown above, only one parameter per object is strictly required. This is the object type which has to be a valid type specified in the used class information file (see Module Metadata).

Slot connections

If there is more than one object, you can establish connections between them. Therefore you have to specify the target slot in the target list of the source slot and vice versa. As you can see, the slot connections are realized like double linked lists. Empty source/target lists can be omitted.

A simple configuration with two objects is shown in the following table.

connected graph example

parameter	value	remarks
obj1.type	filereader	first object
obj2.type	filewriter	second object
obj1.data	obj2.data	connection obj1.data->obj2.data
obj2.data	obj1.data	connetion obj2.data->obj1.data

This results in the graph structure shown in the image below.

connected graph example visualization

Example file: connected.wrp

Limitations

Output slots can have as many targets as wanted. This can be used to implement some kind of observer design pattern.

Input slots can have at maximum one target from which they get their data from. This is useful to be able to query data from this slot when needed.

A valid example with multiple connections is shown in the table below.

multiple connected graph example

parameter	value	remarks
fr.type	filereader	data source
fw1.type	filewriter	first target
fw2.type	filewriter	second target
fr.data	fw1.data;fw2.data	multiple targets of output slot
fw1.data	fr.data	each input slot has ...
fw2.data	fr.data	... only one target!

multiple connected graph example visualization

Example file: multicon.wrp

Parameters

Parameters (as shown in the object inspector) can be set or left unset. Unset parameters will be shown in gray and default to their value given in the class description.

Object inspector showing set and unset parameters

This is useful not to overload the parameter files and to be able to calculate default values (which do not have the same as in the class description) for unset parameters "on the fly" during object instatiation.