elektraLite CP100xt Manual Part One - Manual (Page 69)

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First, before hashing, the fixture type name is converted to upper case, and blanks are stripped. This
means that if you add a new fixture type to the library whose name differs from an existing type only
in the case of the letters, or in the presence or absence of blanks, it will be considered to be the same
type, and will overwrite the previous one.
Second, it is theoretically possible for the CP-100 to reject a particular fixture type name, and require
that the user choose a different one. This happens when two names differ, but happen by accident to
produce the same hash value. Since there are over 65000 possible values, this is very unlikely, but
then again there was the Titanic!!! So, if it does happen, simply change the name of the fixture
slightly, and try again. (It isn’t sufficient to change the case of a letter.)
Another consideration is what happens if fixture data (a fixture.dat
file) is imported from a CP-100
that doesn’t have the same fixture library (the stdlib.txt and userlib.txt files), and the former
contains fixture types that are unknown. In this case, all the CP-100 sees is some fixtures that have
numeric type codes that it doesn’t understand. It has no way of knowing what the actual names of
these undefined fixture types were, since the hashing algorithm can’t produce the name from the
number.
In this case, the CP-100 shows the unrecognized fixture type in the form
'unknown xxxx ', where
xxxx is the unknown fixture type code in hexadecimal notation. It is encoded in apostrophes to
make it impossible to enter such a fixture name in the library file. When selected for display, this
fixture appears to have one
Dim feature but any existing feature values in cues are maintained, unless
the cue is edited and stored again.
Last, it maybe desirable to rename a fixture type. Perhaps an error was made in naming a fixture type,
or perhaps a new version was released and one wishes to append
V1 to the first version’s name.
However, changing the name of a type will render any fixture data referring to that type unusable,
since fixtures are bound to their types by name. This situation is dealt with by including the old type
name in the library equated to the new one:
type old-string
is new-string
This tells the CP-100 to convert any fixtures whose type matches old-string to new-string. No other
parameters or feature definitions may follow. When the CP-100 finds an entry of this sort in its
stdlib.txt
or userlib.txt file, it treats any fixtures whose hash value matches the old name as being
of the same type as the new name. It doesn’t, however, alter the hash value stored in those old
fixtures. (Note that
type and is must be on two separate lines.)