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erikals
10-24-2015, 10:24 AM
after a lot of testing, this is the best way to create a corrective morph in LightWave

this method is better than >
-softfx edit (creates deformation problems)
-sculpt apps (just use modeler instead)
-muscle bulge (no go, as lack of proper paint / weight paint in layout)

...and, the method is so... well... simple.

so there you go, if you ever struggled with it, this is the way.


https://www.youtube.com/watch?v=313H-xNh8y8

jwiede
10-25-2015, 05:19 AM
The geometry being modified in the example really hasn't been deformed by bones much at all, and there is still a clear visual correlation between the undeformed geometry and what needs to change in the deformed case, which makes creating the corrective morph much, much easier. The example shown isn't really much of a "problem case" w.r.t. creating corrective morphs, all told.

The real problem cases for corrective morphs occur when the geometry in question is strongly deformed by bones (typically rotation and transformation), such that it isn't visually obvious what needs to change in the undeformed geometry in order to fix the problem in the deformed geometry. With this approach, those problem cases will require time consuming trial-and-error just to visually identify which elements of the undeformed geometry need to be adjusted, plus determination of which axes of rotation and transformation yield correction in the deformed geometry, before the user can even actually start making the corrective adjustments to the undeformed geometry.

For such problem cases, the demonstrated approach is less efficient than some of the others available in LW (for above-cited reasons).

erikals
10-25-2015, 09:15 AM
unfortunately no superior way to do this in LightWave

stiff paper
10-25-2015, 10:07 AM
Doesn't the Mike Blackbourn method still work?

http://www.3dluvr.com/content/article/118

erikals
10-25-2015, 10:13 AM
it can, if all deformation settings (muscle bulge etc) on bones are inactive and as long as bones use weightmaps

so, no, not quite.

hrgiger
10-25-2015, 10:41 AM
Well if you have corrective morphs, you wouldnt have to rely on weight maps, at least for good deformations. And muscle bulge and joint compensation rarely satisfies. So the Blackbourn method is the best solution ive seen. Trying to guess a corrective morph on an undeformed mesh would be quite painful in any realistic scenario. Best hope they have already addressed this natively in lightwave.

Greenlaw
10-25-2015, 11:58 AM
I agree. The method in the above video is what I had to use in my music video a while back and it was pretty painful. This was before I knew about the SoftFX method.

I'm puzzled about the morph target in the 'Not Working' video--couldn't you just select the corrective points you want to keep, invert your selection and then clear the morph map of the deformation you didn't want? Not a critique, just asking--I wasn't sure if I was missing something in the video.

Anyway, the 'rest' pose in frame 0 really should not have any deformation coming from the rig to begin with. The way to solve this problem is to correct the rest pose first. If the deformation you currently have at frame 0 is what you really want, try using Save Tranformed and make that version your base pose. You'll need to re-rest the bones after swapping the geometry of course. After that, the SoftFX method should work as expected. (Trust me, it's a whole lot faster and easier than jumping back and forth between a posed mesh on Layout an un-posed mesh in Modeler.)

G.

erikals
10-25-2015, 05:52 PM
I'm puzzled about the morph target in the 'Not Working' video--couldn't you just select the corrective points you want to keep, invert your selection and then clear the morph map of the deformation you didn't want? Not a critique, just asking--I wasn't sure if I was missing something in the video.
nope, tried that, and tried just about everything. doesn't work.
not saying SoftFX Edit can't work in some circumstances, as the inaccuracy though not zero, is somewhat low,
but it for sure didn't work on the Alien scene... unfortunately. tried everything.


Well if you have corrective morphs, you wouldnt have to rely on weight maps, at least for good deformations. And muscle bulge and joint compensation rarely satisfies.
sorry, i wasn't talking about weightmaps for the rig, but to use them only in order to be able to export the morph correctly.
muscle bulge and joint compensation was just an example on what kind of deformations that needs to be turned off before exporting the endomorph.


Trying to guess a corrective morph on an undeformed mesh would be quite painful in any realistic scenario
the only method that solves this with 100% accuracy is the method i posted above.


a compressed scene, if someone wants to give it a go >
http://www.erikalstad.com/cgtemp/Alien_Emi.zip

jwiede
10-25-2015, 08:27 PM
the only method that solves this with 100% accuracy is the method i posted above.

Unless I've missed something (entirely possible), what you posted (change in Modeler, check in Layout) is pretty much the "brute force" / "standard" method for creating corrective morphs in LW. It was the pain of that method that led people to seek out alternatives like the SoftFx and other more efficient techniques (but all of which also have substantial limitations).

hrgiger
10-26-2015, 03:00 AM
Unless I've missed something (entirely possible), what you posted (change in Modeler, check in Layout) is pretty much the "brute force" / "standard" method for creating corrective morphs in LW. It was the pain of that method that led people to seek out alternatives like the SoftFx and other more efficient techniques (but all of which also have substantial limitations).

Exactly. You're changing the undeformed mesh in modeler, then to check to see how it affects the deformed mesh in Layout. It's pretty much the epitome of what is wrong with the Layout/modeler split.

erikals
10-26-2015, 03:08 AM
Exactly. You're changing the undeformed mesh in modeler, then to check to see how it affects the deformed mesh in Layout. It's pretty much the epitome of what is wrong with the Layout/modeler split.
true, though the most accurate Corrective Morph method.
a fix vital, hope we see it in LW2016

Greenlaw
10-26-2015, 08:23 AM
I still think all you need to do is kill the morph displacement for the region outside of the elbow. If you get any 'ridging' along the boundary where the displacement was cleared, just run Smoothing in that region to create a falloff.

Sorry, I can't check on that here though. For some weird reason, the mesh in the scene is invisible on my system. The visibility is enabled in Scene Editor and when I select is and launch Modeler, it's clearly there--but I just can't see it in Layout. Anybody have an idea why this is happening here? I can see other meshes in other scenes, just not this one. It's really strange. Anyway, I should have that scene around here already somewhere. Will check on it when I have time.

You might also look into the old Mesh Edit tool from 3D Cel. It only runs in x32 bit Layout though. There might be some other limitations too. I've only ever used it for editing meshes for camera mapping. (I use SoftFX for that nowadays.)

G.

Edit: Actually, now that I've had my coffee, I can tell you that the Mesh Edit tool will give you the same results. The issue is that the whole mesh is being deformed by the rig when you bend the elbow, not just the elbow region. The only way to correct this is the create the rig so that this isn't happening or you can simply clear the unwanted additional morph displacement as described above. Either should be way easier than trying to correct the bad deformation from a completely different pose.

Greenlaw
10-26-2015, 08:46 AM
Also, I can already tell you that editing a corrective morph in Modeler gets highly impractical for certain regions of the body. In Happy Box, I was getting some serious pinching in the character's inner thighs and butt region because of the way they're sitting on the couch, and I essentially used the method you proposed to fix this. Because the twisting was so extreme, it took me forever to get the morph to even close to being 'correct'. I'm not 100% sure because that was done so long ago but for later scenes, I think I wound up modeling the lower body in that pose and freezing the animation below the waste.

It wasn't until 'B2' that I found out about the SoftFX trick and the method was much easier and far more accurate for fixing the characters for that project. I don't think my rig is excessively deforming other parts of the body though, and if it is, I'm sure I just cleared what I didn't want deformed. (Sorry for the slight uncertainty. I guess that was a while ago too.) I've used the same method for fixing creatures in a couple of films since then.

G.

Greenlaw
10-26-2015, 09:11 AM
You know, even though I can't see the mesh, I did notice that the IK is changing the pose from it's 'rest' state at Frame 0--that's probably what's causing the additional deformation you're seeing in your morph target. Try it again with IK disabled (you don't need ik just to bend the elbow.)

I suspect you'll get the results you were expecting. You can re-enable IK after your done saving the morph and clearing SoftFX. (Don't forget to kill the keyframe you created in the elbow.)

G.

erikals
10-27-2015, 05:40 PM
Greenlaw, been busy, thanks for input http://forums.cgsociety.org/images/smilies/arteest.gif http://erikalstad.com/backup/misc.php_files/smile.gif

we're on the same page in several cases, though i can't find SoftFX method to export nicely, tested it a lot, but i shall try to test some more.
....ooor, wait and see if LW2016 fixed it...

Greenlaw
10-27-2015, 06:05 PM
Yes, regardless of method, making corrective morphs in LW really should be easier. A lot easier. :)

G.

tyrot
10-27-2015, 07:46 PM
greenlaw i might have overlooked it .. where is that SOFT FX trick ? any video ?

Greenlaw
10-27-2015, 11:38 PM
Mike Green did an excellent tutorial on the method like 10 years ago. Erikals revived it here: Layout Smart Skinning by Mike Green (http://forums.newtek.com/showthread.php?141813-Layout-Smart-Skinning-by-Mike-Green&highlight=dodgy+softfx+corrective+morph+tutorial)

In a nutshell, you scan your mesh with SoftFX and use EditFX to 'sculpt' your mesh. Not need to save the .mdd, just scanning it with SoftFX is enough to activate the edit tool. For corrective morphs, you pose your character and use the tool to fix any deformation issues you see, then go to the setup frame and use Save Endomorph to embed a new morph vmap. Naturally, you will need to save the object after creating the vmap. Next, remove SoftFX and apply Joint Morph+ to connect the corrective morph to your rig.

As noted earlier in this thread, you need to be sure the mesh isn't being additionally deformed by something else when you save the Endomorph--the mesh really needs to be in its rest state with only the SoftFX sculpting applied. If the rig is setup cleanly and you're not intentionally deforming it in the setup frame, this shouldn't be a problem.

G.

hrgiger
10-28-2015, 03:02 AM
Unfortunately, using editFX has its issues, one of which is that you simply don't have the range of mesh editing tools in layout as you do in modeler so its really only suitable for very simple meshes.

The Blackbourn method of stripping your deformation off of your morph map is the closest you'll get to a real solution of being able to use any of your preferred modeling tools to reshape a deformed joint. The downside is that you need to create 2 morph maps for each joint morph you create. The bottom line is, its all workarounds at this point and its about time that we have a true native solution.

erikals
12-03-2015, 05:49 PM
also read, input from Rebel Hill (Craig) about Corrective Morphs in LightWave
http://forums.newtek.com/showthread.php?149020-Discussion-Thread-for-the-New-Blog-Post-Part-2-on-the-new-Unified-Mesh-System/page8