Transpose

[Andrew Shpagin]

Please post ideas on transpose there.

[Psmith]

Dot Based Posing and Animation

Andrew:

I cannot find the 3D Siggraph paper demonstrating the method I believe to be the best and most intuitive way to pose/animate a 3D character, but here is a developing Japanese product that uses a similar algorithm to quickly pose and animate a 2D character. Just click on the pictures, (ignore the Japanese text, unless you can read it), for a thorough demo of the concept:

UrumaDelviPaint

Your dot system of posing is already very close to this system, but their system needs only the placement of approximate "IK" handle positions, with no need for anchor points. The algorithm seems to be smart enough to know where to begin the bend of a limb and how much to bend and distort it.

What do you think?

Psmith

[akira]

Dot Based Posing and Animation

Andrew:

I cannot find the 3D Siggraph paper demonstrating the method .

It's called "Subspace Gradient Domain Mesh Deformation", you need a coarse control mesh to deform your hi-poly mesh, that's hard for voxel-based mesh.

homepage of the author:

http://www.kunzhou.net/

[Psmith]

It's called "Subspace Gradient Domain Mesh Deformation", you need a coarse control mesh to deform your hi-poly mesh, that's hard for voxel-based mesh.

homepage of the author:

http://www.kunzhou.net/

Akira:

That's the one, alright. Thank you for remembering. Everything on the page you linked is incredibly interesting and revolutionary. I might also encourage you, Andrew, to look at the video demo on that same page, entitled,

Direct Manipulation of Subdivision Surfaces on GPUs

Absolutely stunning technology which would be the solution to so many character animation troubles, and would also increase productivity among character modelers and animators throughout the industry.

I have no idea what the "intellectual property" ramifications would be.

Psmith

[JamesE]

Andrew: Your dot system works great already. I would suggest building on that so that you can connect one dot with another to form a heirarchy. I wouldn't worry about ik yet, just a simple 2 dot heirarchy system that can be expanded upon even to the point where those who want rigs can have them just by adding more dots and organizing them into a heirarchy. At the base 2 dot level you would have a similar system to transpose. Being able to move or rotate or scale the dots is a must, both individually and as a heirarchy. I was wishing for this over the weekend as I finally got a chance to build a full human mesh using the voxel sculpting. I was really missing my transpose tool in zbrush. The move brush just doesn't cut it and causes way too much unnecessary cleanup. Transpose is even more important with voxel sculpting since the density is much higher than with polygon cages and you are starting from scratch.

What would be even cooler down the road is if you could store these control heirarchies and reuse them and also allow them to create voxels much the same way as the curves do. This way I could store a hand or a whole body heirarchy and use it for either deformation or creating a new voxel component to add to another mesh. One hand heirarchy could be reused forever after its initial creation and save so much time for artists doing character work.

On a related note, with merging external objects... is there a way to rotate and scale them before placing them on a voxel mesh? I could not seem to do this, but maybe I've been doing something wrong as I've only started seriously playing with this stuff now. If it doesnt' exist I'd like to request it. Otherwise I'd appreciate any help on how to use it.

[wailingmonkey]

I'd also agree that a zsphere-rig-like capability with the 'dots' would work just fine (as long as it didn't shoot the

sculpt off into z-space like zbrush's does ) And being able to save them would be handy as well...

JamesH, are you envisioning the scale of the dots affecting how greatly they envelope the vox-sculpt as a means

for finer control of the 'skeleton'?

[Mantis]

I found these paper on the web who fit perfectly to the subject.

It's called Real time Volume Manipulation

Here are two pdf who give a simple explanation of it, it seems quite interesting because it build a skeleton based on your volume.

http://www.caip.rutgers.edu/~viksingh/volm...03-RealTime.pdf

http://scompt.com/files/animation/researchpaper.pdf

The full paper can be found there but you have to pay for it.

http://portal.acm.org/citation.cfm?id=827057

And for the balls, after playing with them I think they can be great but can be hard to setup, especially at the joint.

Sometime it should react like a ring who go around the form not like a dot.

Try to move an arm upward, and look at the influence, you will see what I mean.

Maybe being able to move the ball inside the volume could help.

[JamesE]

Actually I wasn't considering the deformation at all, assuming rather that andrew would handle that under the hood. A user controllable system layered on top would be nice, like an envelope/capsule that you could toggle on or off and edit independently, but otherwise I think the default deformation handling should require little tweaking on its own. I generally don't worry about this in zbrush either because I'm just bending and posing and correcting any anomalies with the sculpt tools afterward. I'm really not interested in perfect deformation. That's a losing battle you fight anyway as you cannot account for every situation. I would say just make it as good as possible and I'll be happy even if I can't tweak the deformation at all. So long as I can pose and correct through sculpting that's good enough to start with.

[ldzywsj]

Yes,yes,yes

Andrew,about transpose,you really should have a look at this video:

Direct Manipulation of Subdivision Surfaces on GPUs

http://www.kunzhou.net/publications/subd-gpu.wmv

and the paper at www.kunzhou.net

[JamesE]

Maybe being able to move the ball inside the volume could help.

This should always be possible. It is one of the most useful aspects of transpose in zbrush. I can move the manipulator anywhere I want to get the right deformation. Depending on the handle you grab, the transformation will apply only to the manipulator, or it will deform the mesh. I'd prefer to just see a modifier key for this so that the main behavior is always the same. Grabbing a dot and moving it moves the dot and deforms the mesh, or if you hold a modifier key, it just moves the dot, allowing you to customize how/where the deformation occurs. This would cut down on complicating the manipulators or dots themselves with extra regions or handles that add visual clutter. If you want differentiation visually, it's just as easy to have the appearance of a dot or handle change graphically when you use a modifier key.

...Speaking of which, I really don't like the current implementation of the universal manipulator. It's too cluttered and confusing to look at with multiple color coded transform types running on different axes for scale and movement. Either put both transform types on the same axis with their own handles like any other universal manipulator or make a toggle that changes the manipulator handles.

[philnolan3d]

...Speaking of which, I really don't like the current implementation of the universal manipulator. It's too cluttered and confusing to look at with multiple color coded transform types running on different axes for scale and movement. Either put both transform types on the same axis with their own handles like any other universal manipulator or make a toggle that changes the manipulator handles.

Agree 100% It's very confusing to look at. Here's a video all about Maya 7's version.

http://www.digitaltutors.com/store/video.php?vid=640

Here's a quick one I did of LightWave's where you use the scroll wheel on the mouse or keyboard shortcuts to toggle between modes.

http://www.screencast.com/users/philnolan3...16-187f4cf7b9b9

I haven't used Hexagon, but I like the look of the UM

http://images.gamedev.net/features/reviews/hexagon22/UI.png

[Mantis]

[...] I'm really not interested in perfect deformation. That's a losing battle you fight anyway as you cannot account for every situation. I would say just make it as good as possible and I'll be happy even if I can't tweak the deformation at all. So long as I can pose and correct through sculpting that's good enough to start with.

I was not talking about the perfect deformation, transpose in Zbrush is enough for me and like you I tweak my sculpting when I have to.

But here it can become difficult to stop the influence propagation of a ball, sometime when I was moving the arm it was also moving the spine because I didn't have enough ball, even if I got more than 4 balls on the torso.

It is not really intuitive for the moment.

That's not perfection I am looking for, just a quick and easy tool, like transpose is.

[rimasson]

What i like in the Zbrush tranpose tool :

the ability to Block a part of a mesh.

Precise deformations.

The ability to TWIST a model (ex : a forearm)

[jedwards]

I was not talking about the perfect deformation, transpose in Zbrush is enough for me and like you I tweak my sculpting when I have to.

But here it can become difficult to stop the influence propagation of a ball, sometime when I was moving the arm it was also moving the spine because I didn't have enough ball, even if I got more than 4 balls on the torso.

It is not really intuitive for the moment.

That's not perfection I am looking for, just a quick and easy tool, like transpose is.

Yeah I understand - you really don't want to be posing the fingers on a hand say and have the palm or wrist getting deformed as well. Masking in Zbrush helps control this as rimasson says, and it definitely lets you get down to more precise control of deformation, but I can't help thinking there's got to be a less 'fiddly' way of doing it. A more accurate deformer that can separate finer deformations like a single finger from the other fingers or the hand or worse, even the rest of the body, which zbrush won't do if you don't mask off parts before using transpose. Something that is much more localized without the need to mask would be awesome.

[Andrew Shpagin]

To community: great thanks for so much info!

What i like in the Zbrush tranpose tool :

the ability to Block a part of a mesh.

Precise deformations.

The ability to TWIST a model (ex : a forearm)

Please show how it looks(2,3).

[Mantis]

jedwards: Yes, that's what I meant.

What Psmith show us seems really great, it's like the current ball system but seems really accurate.

I have done a little video for showing you what (I think) rimasson meant by precise deformation and the ability to twist.

In Zbrush the deformation is driven by your mask, it is really simple, when you mask at 100% there is not deformation at all, 0% it is fully deformed 50% half deformed.

Because you can sharpen or blurred your mask you have a precise control of your deformation.

For the twist, when you click and drag the middle circle of the transpose line you are doing a twist.

I captured a video to show you how it works.

http://screencast.com/t/l0iVNeBX

I used a topological masking in the video, the mask is done depending on your topology who is quite helpful

[Taros]

Here is a very interesting example how you can paint bones and bonepathes in blender.

Very impressive: -> http://blenderartists.org/~theeth/bf/etch-...uous_embed2.ogv

Another example: http://blenderartists.org/~theeth/bf/etch-...ching_embed.ogv

[philnolan3d]

What format is .OGV?

[Taros]

You can view it with VLC Media Player, the player is free.

Here are some infos about the video-format on wiki: http://en.wikipedia.org/wiki/Theora

Be creative

Chris

[philnolan3d]

Ohh.. Ogg Vorbis, OGV, Should have thought of that. It plays fine in Windows Media Player, I should've just tried it.