View Full Version : Expression Editor LW 9 Nodes

08-14-2006, 04:19 PM
I am trying to dig into LW 9's Expression Editor, but I think I'm missing something.

In a new scene, there is the default camera and light. The light is keyframed to move along the Y axis. In the Expression Editor, I have Light.Position.Y connected to the == (equals) connected to Camera.Position.Y. When Generate Expression is clicked, I see:

Unsufficient outputs from path token
Generation failed.

Anyone know what I'm doing wrong here?

08-14-2006, 05:01 PM
Easiest way to do this:

Bring up Graph Editor
Select the Light Channel
Click New in the Expression Tab
Clear the Value
Right Click on the Positiion.Y and select "Append to Expression"
it will paste [Light.Position.Y] into the Value
Now Select the Camera in the lower bin
Select the Position.Y in the upper Bin
Press Apply in the Expression area

viola - and virtually no typing

08-15-2006, 12:42 PM
Thanks for the reply, GregMalick. The "Apply To" part of the process was escaping me.

The node based Expression Editor gets two thumbs up (now that I know how to use it.)


08-15-2006, 03:55 PM
i thought the node based expression editor was considered abit of a dead loss and thats why we got relativity 2?

08-16-2006, 07:41 AM
I haven't really messed with expressions via the tab in the Graph Editor, nor am I familiar with Relativity 2. The node-based editor is the first tool I have used for expression building.

Figured it was a good way for me to get into expressions- my algebra isn't bad, but I am no programmer. Should I be spending some quality time with Relativity 2 instead of the node-based editor?


08-16-2006, 07:59 AM
Relativity 2 gives LW's expression editor a complete spanking in almost all respects. It's certainly *much* easier to use and I have never had a need (or desire) to use LW's expressions.

I've been using Relativity in almost every scene I have ever put together since I joined the beta testers for version 0.3.0 back in the mists of time. :)

There does seem to be a rounding error lurking in Rel2, though. No word from the author or NewTek on a fix, sadly. Invoking the bug seems to be related to rate of change in an angle being used to drive an expression (e.g. VH) and occurs when this approaches 0. I suspect it's fixable or at least slightly avoidable. I need to dig at the posted scene by the original reporter (it's bitten me before, I know that much).

08-16-2006, 01:29 PM
Cracked open Relativity; it's great. Thanks for steering me in the right direction.