View Full Version : UserExpressions.lib missing file

Julius Caesar
08-13-2003, 03:08 AM
Hello all,
I am writing a custom expression in order to modify the Light Intensity of 90 lights using a null object as handle. I have found the math model and I would like to write the expression in a customized library. The Expression wizard says that there should be somewhere (in the same place of the configuration file) a file called UserExpressions.lib, but I don't find it anywhere. I have searche all Hard Disk unsuccessfully. In addition, in the file there should be some examples that could help me to write the generic functions I need for my implementation.
Anybody found that file somewhere on the HD? If yes, could this kind person post part of the file so I can inspire for my functions?
Thank you in advance and best regards

08-13-2003, 09:56 AM
Though I have never done expressions/lscripts/etc., Is it possible that UserExpressions.lib file is in the SDK and maybe you do not have the SDK installed? I know it is a separate option in the installer and maybe you hadn't selected it.

This is all just speculation on my part. I have the SDK installed at home and will try and remember to check when I get there.

Tom Speed
08-13-2003, 08:09 PM
From LScript 2.6 release notes:

Expressions UDFs are stored in the \NewTek\LScripts directory within their own directory
called "expressions". A default library of functions can be maintained within this
directory called "library.ls". This library of functions is automatically loaded into the
Expressions engine when LightWave is initialized, and its defined functions are consequently
available to any LightWave expression or Expressions UDFs that references them.

Additionally, individual Expressions UDFs can be stored in their own files in this same
directory. The name of the file containing the UDF must exactly match that of the function
name being referenced. The file may contain any number of other UDFs to support the main
function, but must contain at least a UDF whose name and argument count matches that being
referenced in the expression.

Have you checked where you're saving your expression library?


08-13-2003, 08:42 PM
Yup, just as I expected.....I was wrong. :D

The file does not exist on my machine, so everything I wrote is wrong. At least I mentioned that I didn't know what I was talking about and I was right about that!

Julius Caesar
08-14-2003, 05:34 PM
thank you for your post and for having checked your folders.
In the meantime I have tried to create a file using the info found on the help. Here a "prototype" of the file UserExpressions.lib:


I have put this file in the folder where Lightwave save the file *.cfg. I have restarted LW and I have found the function Dist in the function list of the expresion builder.
I will post a final file later...