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jasond
09-28-2006, 07:52 AM
This is my first expression and I'm having no luck at all. Syntax issues, most likely, but I can't be sure until I have a working solution to compare.

I need to flip up a bunch of notecards on a spiral spine. So, the card x position needs to change with the degree of p rotation. I'll keyframe the p rotation and it'd be nice if the x position just followed automatically.

I'd appreciate any help. Thanks!

Jason

Phil
09-28-2006, 09:39 AM
With Relativity, this is straightforward. You don't mention if you are running 9.0, but with Relativity apply this in the X channel :

P(SELF,t)

Ensure you enable the rotation in degrees button and then scale the X position with a multiplier to get your distance travelled correct. It should be straightforward.

stib
09-28-2006, 09:44 AM
One issue that you're going to run into is that you'll have to write an expression for each of the items, because you can't just do what you would in After Effects for example and write thisItem.Rotation.P

So Expressions might not be that useful for you there.

I think you might need to look at Relativity, if you're using 9. I'm just coming to grips with it myself, so I won't try to advise you on it.

My other tip is that if you right click a channel in the graph editor channel bin you can choose "append to expression" from the contextual menu. Saves a lot of peering at the tiny type trying to make sure you've spelled everything right.

[edit] looks like Phil beat me to the punch there. What he said

jasond
09-28-2006, 10:02 AM
Yes, running 9.0. I'll try it out.

DiedonD
09-28-2006, 10:03 AM
I would like to get into Expressions. Out of curiosuty. I cant find any useful sites to start from scratch. Anything changed a year later?

jasond
09-28-2006, 10:10 AM
This sort of help can make a body lazy.

Thanks again!

Jason

Phil
09-28-2006, 11:18 AM
Relativity rocks *hard* In all the other packages I have used, Relativity is almost always the single plugin that keeps me running back to LW. It's just fantastic. SE/DSFX (Surface Effectors) is the second. I just wish Prem was more.....active in the development of the SE/DSFX 2.0 plugin.

NewTek are supposed to be uploading the Relativity content, but sadly have not managed to find time to upload a ZIP file (!) If I had permission from NewTek, I could make it available in 5 minutes.... I don't, so I can't.

I promised to upload a summary page that condensed all the Relativity tricks and tips from the user group. To my discredit, I completely forgot. Feel free to nag me at phil ~at~ ldex (dot) terica {dot} net if I continue to fail during the weekend :D

zapper1998
09-28-2006, 01:29 PM
Relativity rocks *hard* In all the other packages I have used, Relativity is almost always the single plugin that keeps me running back to LW. It's just fantastic. SE/DSFX (Surface Effectors) is the second. I just wish Prem was more.....active in the development of the SE/DSFX 2.0 plugin.

NewTek are supposed to be uploading the Relativity content, but sadly have not managed to find time to upload a ZIP file (!) If I had permission from NewTek, I could make it available in 5 minutes.... I don't, so I can't.

I promised to upload a summary page that condensed all the Relativity tricks and tips from the user group. To my discredit, I completely forgot. Feel free to nag me at phil ~at~ ldex (dot) terica {dot} net if I continue to fail during the weekend :D


Ok we will do that

stib
09-28-2006, 07:41 PM
there's a relativity user group? Any details (feeble web search effort produced nothing on the first page so I gave up)

Phil
09-28-2006, 11:07 PM
There....was. http://groups.yahoo.com/group/relativitylist/ - it died really in 2005 when Prem stopped shipping builds of both Relativity 2 and SE/DSFX.

Sadly, the group is also members only and Prem has to approve the application to join. Since he's not really been around much, there have been no new sign-ups AFAIK.

I hoovered up all the interesting posts and content during OB so that they would be safe if the group were closed. I just need to pull it all together for public use. ;)

I have almost all of the Relativity tutorials and content available, except am uncertain about copyright status for Prem's own tutorials and content. He has never covered this in either of the replies to the various emails I sent asking about this matter, and other things. It's unclear just how much NewTek acquired and how aggressive they would be about defending any perceived copyright breach if I were to upload everything I have backed up.

*shrug* I'll upload what I feel comfortable uploading. Everything else waits on someone from NewTek, or Prem, showing me that there is nothing to worry about.