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Domains for Elements

With the domains for elements $Domains$, all possible values are specified, which an element may take, no matter whether this value is explicitly specified or is given by a variable. So the $Domains$ specify all values, that can be taken by elements. The minimum and maximum values are determined with it. The presentation of the multimedia device may be adapted/scaled to these values. If for example, a film should be displayed on a 100 cm (centimeters) wide screen display and the dimension of the horizontal direction is given as from -5 m (meters) to +5 m, then points at the horizontal value -5 m in the Fib object will be displayed at 0 cm on the screen and +5 m will be displayed at 100 cm (0 m at 50 cm, etc.).

For the display the domains of the top most root-element are crucial. Contained root-elements can also specify the domains, but these are ignored when the Fib object is display. Therefore, the top most root-element must specify all domains relevant for the displaying the Fib object.

The in $Domains$ contained domains are inherited by the in the current root-element contained root-elements. Contained root-elements may also overwrite all inherited domains. The input variables $InVar_i$ are root-element specific (they are not valid in any contained root-elements), their domains are therefore not inherited, because this is neither reasonable nor desirable.

When a domain for an element of the Fib object is not given or inherited, it has as its domain its default domain. If there is no default domain for a particular element, its default domain is $integerB(16)$.

Another special feature arises, when the database objects inherit domains. Even for root-elements of database objects, it is useful to adopt domains for some elements. This is usfull for example for the dimensions of a database object, which should eventually be adopted to the displayed multimedia object. If for example a database object is a general triangle, wher its size and key points are set by input parameters, the dimensions for this database object can not be determined in a reasonable manner. For this reason, the inheritance of domains for a database object will be treated as if the database object is a sub-root-object in the root-element, in which the main-Fib-object uses the database object. Thus the database object inherits the domains, which are also valid for the external subobject element, for which it is used.

Thus in the top most root-element of a Fib object (such as a database object), domains can be omitted if they are determined by the calling/using Fib objects or mechanism. For these Fib objects the corresponding value domains $DomainsValues$ should be given for the missing domains in their top most root-element, in order to be able to store the objects.


next up previous contents index
Next: Domains for values Up: Domains Previous: Domains   Contents   Index
Betti Österholz 2013-02-13