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File: volume.png (125 KB, 1300x704)
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I exported the Daz3d Gen 3 female character to look at the skin weights in Maya. I've never seen volume preservation like this before with out fancy blend shapes or something but it seems like they did it here with only skin weights.

How did they get the weights so perfect and how is the bottom keeping its volume when bent this way?

In my image on the right you can see a normal smooth bind and on the left is theirs. I've tried painting over their model myself but can't get the same results. The butt always collapses.

HOW?
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its shitty DQ skinning mate
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>>524348
Oh snap. why have I been using linear blending all this time... Does dual quaternion skinning work in Unity?
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>>524350
oh I guess it's unsupported in game engines. There's got to be a way to get it to work in unity or maybe use linear but get a similar method?
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>>524347
To preserve volume using standard linear blending (only availible in all game engines I ever worked with) you gotta have some additional tricks up your sleeve.
Here's some valid strategies I employ in my own work to improve deformation across the full motionrange of my rigs:
- Make your rig pose with the limb prebent halfway between the extremes of it's motion range as this will minimize the amount of compression and stretching occuring.
- Use additional bones to combat stretch. For example add things like a knee cap or a butt cheek bone set to orient itself at 50% between the hip or knee respectivly.
- Use additional bones to combat compression. For example add a heel tendon bone to the back of the ankle looking towards the knee region at all times.
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>>524353
In max, which is what I'm using those last two bulletins would be setup using the 'Orientation constraint' and the 'LookAt constraint'. Inside the game engine these constraints would need to be replaced with simple scripts performing the same function on your rig as systems like that do not export into engines.
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>>524353
I did see some extra joints even with this daz model between the hip and knee as well as the two arm bones. I guess its for twists but also for what you are talking about.
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File: butt_bone.png (355 KB, 1783x1234)
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>>524347
An easy way to preserve volumes if you can't do dual quat is to add bones. Here I have a "butt bone" sticking out that's basically constrained to rotate half the amount of the leg rotation, and the result is very convincing.
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>>524357
Good plan. I've tried that before and I get decent results but nothing quite like how dqs calculates things.
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does dual quaternion skinning with with Unity3d? do I need a plugin or something? Importing a normal mesh won't bring in the dq skinning information.
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>>524360
nope. Unity only accepts linear skinning which looks like dick. You need corrective blendshapes to fake volume preservation.
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>>524361
>nope. Unity only accepts linear skinning which looks like dick.

Linear is sufficient if you know what you are doing and implement stuff that's been mentioned in this thread.
Basically if it looks like dick, that is all your fault.

> You need corrective blendshapes to fake volume preservation.

There is nothing fake about the preservation of volume generated by a blendshape.
But using blendshapes is only effective if you stay withing the framework of maya, max etc.
They're a bad solution for engines since they'll add complexity to the process and may be ill-implemented if available at all.
Extra bones will always work so learning how to use those will provide the silver bullet to kill that bad skin beast every time.
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>>524363
> Linear is sufficient if you know what you are doing and implement stuff that's been mentioned in this thread. Basically if it looks like dick, that is all your fault.

Linear is an ancient cheap and outdated method thats causing lots of setbacks and workaround in videogames and cause terrible rigging artifacts that you can see in more than half of the big games out there.

> There is nothing fake about the preservation of volume generated by a blendshape
Yes there is. DQ makes sure that the rig has accurate vertex instructions so the vertex shader bends things naturally like they should when limbs are deformed.

Corrective blendshapes pushes vertices of your model with linear interpolation and if you want it to look like DQ, you need to add corrective blendshapes for many bending angles for all the limbs one by one. Which ironically costs more processing power than DQ. And if you wanna sculpt or modify your rigged model, too bad because you have to go through all of that corrective blendshape retardation again.
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>>524363
>>524364
oooh getting spicy in here
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>>524363
>They're a bad solution for engines since they'll add complexity to the process and may be ill-implemented if available at all.
They aren't a bad solution, it kinda depends on the situation. Personally I favored extra bones because that meant I didn't have to add blend shape support or a dual quat shader so it seemed simpler code-wise, but that kinda only changed the problem as I then had to add bone partitioning (ie because more bones are necessary it pushed me over the 64 bones per uniform limit and I had to write code to split the mesh into 64 bones chunks, though I'd have needed it in the long run anyway).

But for reference Naughty dog combines all three methods, ie they have dual quat *and* extra deformation bones *and* a bunch of corrective blend shapes:

https://www.youtube.com/watch?v=myZcUvU8YWc
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>>524364
>that you can see in more than half of the big games out there.

While this is true you seriously underestimate just how smug it makes me feel whenever I see some AAA riggers piss poor work in the games I play.
Whenever you crouch and see the knee's turn into bent straws in a game that have sold millions of copies you wonder why you even struggle towards doing things right.


> And if you wanna sculpt or modify your rigged model, too bad because you have to go through all of that corrective blendshape retardation again.

I dislike blendshapes personally, and that is a big part of the reason I avoid em. Extra bones however solve these things while keeping it simple.
It beats DQ in performance too, which may be a big thing depending on the number of actors in the game.

>Linear is an ancient cheap and outdated method

It's a well understood and computationally efficient approach which problems have known solutions and workarounds.
DQ is far away from being anything like a standard as of 2016.
Don't be one of those people that immediately must dismiss something the very hour never tech is gaining traction.

>>524370
> for reference Naughty dog combines all three methods

Naughty dog can employ a fleet of artists and programmers so they can do pretty much whatever they want.
Most of us wont be in the position of that kind of luxury in R&D to implement and tweak these kind of things. We'll have to make do with more out-of-the-box type solutions.
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>>524372
the same DQ guy here.

I agree that it's enough since you can hide the shitty deformations with limiting animation and other meshes, but we're purely talking technical elements and linear rigging is just evil. You will never get the quality of a rig you made in Maya with DQ when you export it in a game engine. And DQ isn't some super duper high-end technology thats impossible to implement. It's nothing more than a different skinning algorythm and has been around long enough.

I'm just dissapointed that we can't use the amazingly helpful rigging solutions in game engines. They add tons of irrelevant shit with every update but not something awesome like DQ.
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>>524373
>I'm just dissapointed that we can't use the amazingly helpful rigging solutions in game engines
You can get literally thousands of fps with gpu DQ skinning nowadays mate.
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>>524374
he's talking about indie-friendly middleware game engines. Neither UE4 nor Unity support dual quaternion out of the box.
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>>524377
> out of the box
Is there a tweak to implement DQ to any of them ?
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>>524378
Not in Unity and in UE4 only if you're willing to overhaul the source code to add support. Official stance from Epic is they got rid of it because it required a second render path.

Cryengine supports it though
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File: topology spider.jpg (105 KB, 736x1233)
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>>524379
They're working on adding dual quaternion skinning for Unity6 which is going to be more animation focused.

https://www.youtube.com/watch?v=FQhlnsbgrL0
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>>524372
>Skyrim
>Skyrim
>Skyrim
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>>524407
that's a clean topology
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>>524364
>And if you wanna sculpt or modify your rigged model, too bad because you have to go through all of that corrective blendshape retardation again.
Actually it's just a matter of workflow, using attribute transfer or a mesh deform cage to decouple the blendshapes from the actual mesh basically takes care of the problem.
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>>524347

Daz uses a combination of Triax weighting (where each rotation has it's own weight map) and Joint Controlled Morphs to make their figures bend so well in Daz Studio.

To make the JCM you pose the figure in it's extreme pose and export it. You then correct the awkward deformations around that bend in a modelling program and load that as a morph. Then you set up a controller where as the figure bone is moved it applies the morph proportional to the movement of the bone so in the end the figure bends without the wonky distortions that a simple weight map would produce.

There isn't really a way to export a Daz figure with the triax weighting and JCMs intact. When you export it as an FBX it converts the figure to General weightmap instead of Triax and the JCMs are lost.
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>>524407
>that topology
>focusing on joints and muscle folds
Why don't people do this more often?
It looks perfect for all needs.
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>>524472
>Why don't people do this more often?

Very few people comprehend all stages of the process, you gotta be a modeller, a rigger and an animator rolled up into one to be effective at developing stuff like that.
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File: weights.png (256 KB, 1606x666)
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Auto weights never work as intended. Here's what I use at the lowest subdivision
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>>524475
that's but some weird topology there m8
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>>524472
you do the topology that suits your needs. There's no one-size-fits-all solution like you think you see in that model.
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>>524456
>Daz uses a combination of Triax weighting (where each rotation has it's own weight map) and Joint Controlled Morphs to make their figures bend so well in Daz Studio.
Used to. Genesis 3 is DQ skinning and they've thrown Triax under the bus.



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