I use 7.0 231 apprentice on linux. It's written that variables can be up to 5 characters long, but when I use about 5 custom variables with names longer than one character, some of them just dont work=scrubbing them make no difference. as soon as I change them to one character it turns ok.

what could cause such a nasty behaviour?

P

I'm sorry for the confusion. LSystem expression variables can only be one character long. The LSystem expression parser is very character driven and has this as a rather deep built in assumption. (There is an internal array 256 entries long to store all the variable values, for example)

I think you got the reference to 5 where it says there can be up to 5 userdefined variables. This is no longer the case now that we have multiparms to define user variables, you can now have considerably more. You are still limitted by the built in definitions of:
a, b, c, d, g, i, t, x, y, z, A, L, T, U, V, W.

- Jeff

Thanks for a reply.
Now I'm sorry because of my obvious misinterpretation. In l-sys html help in limitations to the rules section there stays:“Variables can have up to 5 parameters”.
I tried a simple example with multi character variable which worked so I continued to use them without concern.

Could you explain or point where to find info about “multiparms” for variables?
What does that mean we can use up to 5 parameters for a variable?

Is there any more in depth houdini specific l-system manual?
I went through many algorithmic botany papers, but I'd like to know more details about houdini l-sys implementation.

Thank you

Peter

anybody?

Is there any more in depth houdini specific l-system manual?

The best thing I know, is to get hold of an old version of Houdini 5.5 and get the PDF document. A whole chapter was about L-System. Some of this is/will be in the L-System help cards in the new version of Houdini.

Hello,

here you can find a chapter on L systems:

http://www.sidefx.com/community/download/extras/userGuide/houdini5.5_tutorial_guide.pdf [sidefx.com]

or:

http://sweb.cityu.edu.hk/sm4123/4123-5320/week7/l-sys_TUT_01.html [sweb.cityu.edu.hk]


bernard

Thanks,

I've read houdini manuals but they don't cover the problem.
Maybe it's not about l-system but general knowledge about attributes and parameters in houdini.

Peter

peliosis
Could you explain or point where to find info about “multiparms” for variables?

In the Values tab of the LSystem SOP's parameters, go to the button where there is a Number of Variables parameter. Click on the More button.

Ah that thing!

I used them before starting this thread. I olny hoped they can be more than one character long
There are not too much of them for a stubborn heavy l-system enforcer

Thanks a lot edward for answering this almost dead thread