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jeric_synergy
12-08-2012, 02:43 PM
reposting because this question got buried down-thread....

Nodal: Moving _just_ two points nodally -probably dead easy, but....

OK, to make this illlusion work, it would be helpful to move JUST two points from different objects such that they match up in space.

See attached.109679

The current object already has the XY of its pivot point nodally fixed to the XY of a specific point on the other object, as you can see. To complete part of the illusion, the indicated points should match up too: I want to move the left point to coincide with the right, although the right is morphing.

But, I can't remember/suss out how one can specify a specific point via the nodal displacement system for displacement, while leaving the rest alone. RH has been at pains to get me to understand that it (the nodal displacement editor) not any one point, it's all the points simultaneously, but in this case I want it to be just two specific points moved to align with two other points on a different morphing object.

(A hacky work around would be to assign two bones w/weight maps to just those two points, and Move the bones nodally, which I DO know how to do, but that is one ugly solution.)

Click image for larger version. Name: InvidPoint.jpg Views: 14 Size: 545.2 KB ID: 109670

+++
To facilitate extra suggestions on how to address problems like the paper intersecting w/the bookcover when the cover bends shut, I'm attaching the scene in its current unfinished state.

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RebelHill
12-08-2012, 04:10 PM
The spot info is giving info about ALL spots. The input to the displacement destination node ofc also goes to ALL points... but you FILTER which points in the node editor in the same way as any other area of LW... image maps, weight maps, etc. So get your 2 points in their own WM, and use the WM node to filter your effect to apply to just that area (either via some opactiy input, or abusing a gradient, whatever.)

jeric_synergy
12-08-2012, 04:27 PM
Ahhhh, weight maps!!!! :foreheads

In this case, I believe I'll need two, one for each point I need to move, since I'm attempting to line them up with (semi)arbitrary other points.

LOL ;D, I know I must seem irredeemably thick on this, but perhaps another user w/more pride than I will benefit from my willingness to reveal my dimness. :beerchug:

jeric_synergy
12-09-2012, 02:06 PM
OK, taking another stab at this. Again, this is me sorta babbling out loud so readers can see where I'm going wrong in my conception of how nodal displacement works. :bangwall:
109694
I've got a w.map assigned the point I want to move, at 100%. (NONE of the rest of the points in the object are part of the w.map, perhaps this is causing me problems?)(EDIT: I added the rest of the points to the w.map at 0% just in case.)

Point 1 (P1) is the point I'm trying to move. P2 is where I'm trying to get it to move to.
109696 109697

Trying to use DPKit's MOVE node (could someone fill out Denis's explanation for dunderheads such as myself? It's 'waayyYYYYyy too terse for common folk. Or sub-common folk.), it seems I should generate a vector of (x2-x1,y2-y1, z2-z1) to use as an input into the MOVE node's "Move" input. I have P2, but how do I acquire the P1 SELF point coordinates to generate the vector? Here's my start at such a network:
109698

Here's the packaged scene:
109699

Thanks for any insights. :help:

adk
12-09-2012, 04:38 PM
In this case you're probably overthinking this a bit. Your weight maps affectively filter out all the unwanted points so you only need a very simple node network for this to work.


... EDIT - actually I'm underthinking what you re trying to achieve jeric_synergy. Please disregard all of the above. Let me see if I can nut this out.

jeric_synergy
12-09-2012, 05:06 PM
Thanks, adk. --If there were just a "RELOCATE" node, that would simply put a point at another point, I'd be done*. But I (over?)think it's DISPLACEMENT, not LOCATE-MENT, and hence requires a vector to displace the point in question to the destination point.

AND, of course, that point is both Moving and Morphing.


*that's why pinning an entire object to a point is easy: Nodal Motion is "Locate-ment". My fallback solution is single-point bones and Nodal Motion.

adk
12-09-2012, 06:38 PM
This is a very simplified version that has two boxes moving + rotating + being morphed (left had side of gif) & then sticking one point from one box to another point on the other box (right hand side of the box).
You effectively only need one weight map (100 %) of the point you're trying to relocate & the point index numbers of the points you're interested in "sticking". Easy enough to find in modeler.

Hopefully this works for you mate :thumbsup:

PS: This only uses DP Kit Point info node & displacements. Not sure what NodeItemMotion did in your scene as I think that's the old version of DP's node that I don't have here at work. So your scene does not load 100% for me.

dwburman
12-09-2012, 07:36 PM
something like this?

Constant>Integer - set to the point index number of the point you want to move.

... so what adk said :D

jeric_synergy
12-09-2012, 10:20 PM
PS: This only uses DP Kit Point info node & displacements. Not sure what NodeItemMotion did in your scene as I think that's the old version of DP's node that I don't have here at work. So your scene does not load 100% for me.
Thanks a ton ADK, I'll look at this tomorrow but it sounds like it should work.

The NodeItemMotion was Moving the LEFT pages so that that object pivots on a point on the RIGHT pages object. Basically, between the displacement AND the nodeItemMotion, TWO points on the Left pages correspond continuously to two points on the RIGHT pages, giving the illusion that there is something with a bit of area connecting the two.

I guess it's time to update my DPKit.

Thanks again, REALLY appreciated.

Clarification: there would actually be TWO points that would be moved to correspond to two different points on the target object.

jeric_synergy
12-10-2012, 02:15 PM
This is a very simplified version that has two boxes moving + rotating + being morphed (left had side of gif)
ADK, thanks again for solving this.

I simplified your network to the following:
109734
While it would SEEM that one should be able to replace the SUBTRACT and SCALE nodes with the SUBTRACT SCALED node (I know...), in fact that does not work in this case. (Perhaps if the w.map were prepped differently?)

For user convenience I renamed the nodes to functional descriptions (an action I have severe misgivings with, since it can make it impossible to reverse engineer a node network) and attach it here.

109735

adk
12-10-2012, 02:36 PM
No problem, glad it worked for you. I should have mentioned that I needed to split & recombine the vectors as doing what you have above did not seem to work for some reason? I kept getting weird displacements. Also, I plugged in another transform vector down stream & you'd think that only the filtered points would be affected (as that's what's effectively being output by the flow) but for some reason all points were taken into consideration ? That's some weird logic there somewhere & I'm not sure if it's a bug or just a lack of understanding on my behalf - would not be the first time :)

jeric_synergy
12-10-2012, 02:48 PM
Hmmm, I'll have to look at it again: I just swapped it in and it seemed to work, but perhaps I wasn't seeing some subtleties.

YEAH: when one uses a SUBTRACT SCALED node instead of SUBTRACT and SCALED, although it should be functionally identical instead ALL the points move, so I'm not sure what the logic is, and I just can't take another spell on the dunce chair.

I'll go back to my particular scene and see how it works out.

NOW, of course, I have a problem: I actually want to move TWO points (not just one), and I don't think this methodology will work, since the Destination Point is essentially static.

So, a more generalized statement of the problem is

"How does one connect N points on moving & morphing Object1 to N points on moving & morphing Object2?"

adk
12-10-2012, 03:43 PM
Two points stuck respectively to another two is no problem & it doesn't matter if one / any / all are static or moving / morphing I imagine. Subtract seems to work as expected for me now as well ? Weird - must have been a hiccup somewhere.
Here's the scene that demonstrates this.

jeric_synergy
12-10-2012, 06:39 PM
AHHHhhhhh, with the proviso that it's one Weight Map per displaced point. Brilliant! Lovely solution! :bowdown:

BTW, as others have said, when you use the IKB move tool, the nodal point displacement displays in REAL TIME, unlike the normal Move/Keyframe paradigm. That's very nice indeed.

jeric_synergy
12-11-2012, 01:23 AM
Never could get it quite right, then tried removing the NodeItemMotion. Bingo, dammit.

The function of the node item motion was to pin the pivot point of left side of the book to a point on the right side. Unfortunately this seems to mess with the displacement network.

It might be possible to compensate for this effect and add/subtract that compensation of the Items motion into the displacement of the point, but that seems a little involved for a hobbiest project. To complete a full "book-rig" though I think it would be necessary.

adk
12-11-2012, 03:00 PM
Never could get it quite right, then tried removing the NodeItemMotion. Bingo, dammit.

The function of the node item motion was to pin the pivot point of left side of the book to a point on the right side. Unfortunately this seems to mess with the displacement network.

It might be possible to compensate for this effect and add/subtract that compensation of the Items motion into the displacement of the point, but that seems a little involved for a hobbiest project. To complete a full "book-rig" though I think it would be necessary.

If I get a chance today I'll have a look at your scene & try to see if I can figure anything out. Any chance you can post a grab of what's happening with the motion nodes. So that I can replicate it here. Or update your DP Kit & repost the scene - then it should load fine ;)

adk
12-11-2012, 07:04 PM
I managed to open your scene in an old version of 9.6 that has the old DP Kit so I think I got most of it right in terms of what you want.

With the same node idea for displacement of the points & a slightly tweaked setup for nodal motion I got this to work, sort of :)
F9 renders correctly while F10 has a bug ??? Not sure if this is my shorfall with regard to displacement order, world / object co-ordintates or an actual issue ?
Maybe someone can chime in & have a peek. This is a stripped down version of your scene & uses latest DP Kit jeric_synergy.

PS: Maybe there's something borked with this scene. I'm trying to strip the LHS page from all motions / deformations etc & shift click on the envelope button does not remove them as it normallly does ?