View Full Version : Animated Lathe - used to work, not now!

09-28-2011, 12:19 PM
Hi all. After hours of messing around I'm admitting defeat and need help.

Basically, my animated lathe used to work but now it doesn't. The lathe itself is referenced to the rotation of another null using DPkit item info. I had it so that the lathe would follow the null rotation perfectly, ie, 360 = fully completed lathe. But for some reason it's stopped working and I'm only getting a partial lathe when the null hits 360. I've been through all the preferences, tried numerous bodges but can't get them to line up again. Can anyone else pick it apart - theres a free animated lathe in it for you :)!

Big thanks!

09-29-2011, 08:12 AM
Can anyone help me out here - tearing my hair out?! I've opened the scene where it's working and copied the settings and nodes to my scene where it isn't happy and it goes back to not working. Is there some king of co-ordinates setting in my scene I might have accidentally changed?

09-29-2011, 08:24 AM
hehe nice example of an issue due to colorspace. Set colorspace to linear and your issue is solved.

Your problem is that the value is being changed in the "gradient" node. If you leave that one out (and lose the lathe effect, but just for the idea), it works. So that suggests a coloring issue. Turn CS to linear and all works.

Not sure why it does that, have no more time to check it out but I suppose the color gets gamma'ed and you do not want that. Just find a nodal way that keeps it vectors and you'll be fine.

edit: ok the solution is easy. Dunno why you went the gradient way anyway, took me a bit to understand your plans :P

Solution is way easier, swap the gradient node with the Math-> vector -> scale node
Plug in vector and scalars you got and done whatever CS.

Makes more sense too. Your weightmap is now Scaling the Rotation vector (which changes) and feeds it back into the rotate node.

09-29-2011, 08:29 AM
Hu, what!?!!! Just flipped to Linear and everything is good. Thanks so much Hieron! I had no idea flicking this switch changes everything internally - could have a lot of implications if I use colour channels to do vector stuff.

Once again, THANK YOU!!!!!

09-29-2011, 08:30 AM
Np! :)

ps: it's a good thing that that switch does change things around internally. Usually :) Here the CS system gamma's the gradient colors usually and you wouldn't normally mind since when picking them, you are shown the correct value. But when you feed it a vector, you wrongly assume the vector is what gets put in, but it will be gamma'd as well. You could wonder if that is ever a good thing to do... I think NT just forgot to make that exception.

*quickly goes back to his own projects and issues :)*

09-29-2011, 08:32 AM
OK, so leaving "Picked Colors" to Linear seems a good way to go for the moment......

09-29-2011, 08:34 AM
No no no :P

You need to use the Scale node :P I added it later to my first reply. It makes more sense too.. If possible, just stay clear of mixing vectors and colors I guess. Here it is perfectly possible to stay scalar and vector.

Using CS is quite nice, so it would be sad to stick to linear for this reason alone.

09-29-2011, 08:37 AM
Yes, you're right... I was thinking short term just to get this bloomin' thing finished (I've wasted too much time on it already!)

PS, your solution worked like a charm and sorted out another issue I was having with flipped polys :thumbsup:

09-29-2011, 10:13 AM
:) No idea why it fixed those, but yay! :)