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jimiclaybrooks
09-23-2017, 08:31 PM
Hey, can someone tell me what I did wrong with this spline path for my fish? 137990 As you can see from this image, the fish flips upside down. Since I'm new to the spline tool, I don't understand what this is, and I haven't been able to rectify it. Clearly, there are some things that I need to be careful of. Thanks

Sensei
09-23-2017, 08:43 PM
Take a look at where are pointing red, green, and blue arrows.
On screen-shot that you made green arrow is pointing up.
Where it's pointing on just previous key?

jeric_synergy
09-24-2017, 12:00 AM
It's a simple fix, if I can remember it.... for one thing, try disabling BANK in the Motion Path.... gah, I know I had the same problem b4, and it's simple, but not exactly intuitive.

If you can upload your scene, that's the best way to get a good answer.

++++
OK, built a test scene and remembered: if you are using the RIBBON display, you can see where the kinks occur. To git rid of them you rotate the elements (usually nulls) that make up the Spline. Basically you want them to point to the next element in the chain. You can do this by hand, but that sucks and what if you move something? Better is, make every link/null in the chain TARGET the next link in the chain.

It's a bit of a PITA for any significant number of nulls :( -- I can't remember if there's a script to do this for you.

Also, turning off BANK only works in short segments, I don't remember why.

jimiclaybrooks
09-24-2017, 05:08 AM
So when I used shift spline transform, each null was controllable in all of the channels. I could ever rotate a null and move the parented nulls that were down the chain if I wanted to. In this case, correct me if I'm wrong, I can't do that, or can I?
Seems like this is better and worse, if that's possible. I'll keep fiddling with it to see what I can do. Thanks for the help.

lertola2
09-24-2017, 06:59 AM
So when I used shift spline transform, each null was controllable in all of the channels. I could ever rotate a null and move the parented nulls that were down the chain if I wanted to. In this case, correct me if I'm wrong, I can't do that, or can I?
Seems like this is better and worse, if that's possible. I'll keep fiddling with it to see what I can do. Thanks for the help.

You can do all that with spline control but you have to get the nulls pointing in the correct direction. In this screen shot all the nulls in the spline are not rotated. Surprisingly to me splines often work fine in this condition. But this one has a kink in it:

137994

But you can easily rotate all the nulls in the spline correctly by setting the rotation options for all the nulls to Spline Control in the Motions Options panel:

137996

Set the Heading and Pitch to Spline Control. If you want the spline to stay as upright as possible leave the Bank on Key Frames. Or put the Bank on Spline Control also if you want the ribbon to twist along the spline. Next press Return to set a key frame for all the nulls in the spline. Then set their motion options back to Key Frames in the Motion Options panel. Now you should have a spline without kinks and you have full control to move and rotate your nulls. (Ignore the attachment below)

jeric_synergy
09-24-2017, 08:40 AM
But you can easily rotate all the nulls in the spline correctly by setting the rotation options for all the nulls to Spline Control in the Motions Options panel:

137996

Set the Heading and Pitch to Spline Control. If you want the spline to stay as upright as possible leave the Bank on Key Frames. Or put the Bank on Spline Control also if you want the ribbon to twist along the spline. Next press Return to set a key frame for all the nulls in the spline. Then set their motion options back to Key Frames in the Motion Options panel. Now you should have a spline without kinks and you have full control to move and rotate your nulls. (Ignore the attachment below)

Rats: that's what I forgot: you use SC to align the nulls by referencing themselves. Much faster, although I think mine allows you to animate the nulls w/o kinks appearing.

jimiclaybrooks
09-24-2017, 08:58 AM
Thanks guys, I'll attend to that as soon as I get back from the tennis court. (Gotta git my workout) I also have this issue with the same scene.137997 137998 I went to my old standard, LW Tips & Tricks, and it had a tip on doing the spotlight on the water, but with the recommended settings this is what I got. What I want is the refracted light in the picture with the whale, with the nice swirls of light on the fish and the ocean floor, (when I put it in). Can someone tell me what settings are used to get this kind of lighting? I can increase the light, but the refraction of the light rays is what I can't get. And the spot looks too much like a spot, and not enuf like the sun shining on the water. Thanks
BTW, my semi-educated guess would be to somehow break up the light before it hits the waterplane, because I don't see that happening with the waterplane itself. Am I wrong?

MonroePoteet
09-25-2017, 08:43 AM
The general technique for these type of light rays is to use Volumetric Light on a Spotlight with a Projected Image for a still, or a sequence for an animation. The Projected Image sequence can be generated using LW's built-in procedurals (not very good without a lot of work), or the Caustics Generator available here:

http://www.unrealtexture.com/Unreal/Downloads/3DEditing/UnrealEd/Tools/CausticsGenerator_v1.4/

Attached is a very simple sample scene demonstrating the technique using a sequence from Caustics Generator, but note that the image sequence used in the .MOV is not attached for size restriction reasons.

138012
138013

As well, user dmind uploaded a very nice underwater scene years ago:

http://forums.newtek.com/showthread.php?126907-Underwater-Scene

mTp

jimiclaybrooks
09-25-2017, 06:08 PM
Thank you so much for your help Monroe, this is great stuff!! I'll have some time tonite to look at this and take it apart.