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Nenox
09-25-2003, 03:11 PM
Hi People.

A simple question about blendshapes.

When rigging a character I have always been advised to delete my blendShape targets before animating the character. It obviously speeds up deformation. I've also been told to keep a copy of my targets if i wanted to modify them later.

The question: Can you reimport your target shapes back into your scene, after they have been exported and deleted, and somehow have the blendShapeNode reconnect to them? Or is it simply a matter of deleting the relevant targets from the blendShapeNode and recreating them with the reimported targets all over??

Or is there another way to go about this?

Sorry for the really basic question. I should know this allready.

Thanks,
Nenox.


ps. If someone could clarify how and why people run certain constraints through color/shaderNodes or point to a www..; I would be very happy :love:

dwalden74
09-25-2003, 04:17 PM
If someone could clarify how and why people run certain constraints through color/shaderNodes

You shouldīve posted this one as a separate thread. I think itīs an intersting topic. First of all, different people are going to do things differently, and therefore "what can be done" with shader nodes will vary tremendously depending on each personīs use.

I personally use shader nodes in character rigging because:

a) I passionately hate expressions and feel that they just clutter up the scene.
b) Shader nodes are probably the fastest way for Maya to make mathematical calculations on given connections (although this varies depending on the usage).
c) Itīs quite easy to script shading node setups. Anyone whoīs tried scripting expressions knows how much of a pain in the neck it is.
d) Shader nodes for me is a very "clean" way of working, and given that theyīre direct connections I donīt have to worry about loosing these connections when I import or reference files.

One simple example of a practical use of shader nodes is when you need to "blend" two different nodes together (sometimes called "weighted blending"). For example, I always use a "reverse" node for blending 2 point or orient constraints. Iīve seen other people do this via an expression, but the reverse node for me is a much faster way of getting this done: a "blend" object attr will drive directly one constraint weight (W0), and the other constraint weight (W1) will be driven by the "blend" attr connected to a reverse node. Quick and easy. I have many scripts that Iīve written especially for creating shader node networks for different situations.

If you want to see some of other examples of shading node networks you can download my dwRiggingTools auto-rigging scripts from my website (address below). Several of these scripts were written simply to automize repetitive shading node networks. All the math calculations in the character rig (blending, stretching, etc) are done via shading nodes. In general, itīs a very fast and efficient way of working, IMHO.

Iīll let the blend shape question be answered by someone who uses them more often than me ;) .

:beer:
David

Nenox
09-25-2003, 04:24 PM
Damn.. you the man!!

Thanks a lot. I'll have a look at your scripts and riggers for sure. (I was planning to some time soon anyway) :buttrock:

I have on occation used the Multiply Devide node for reversing values, instead of using expressions or SDK. I don't know if that's what you refer to as a shader node?

The reason I ask is that I seem to recall someone using the Blend Colors node in conjunction with orientconstraints. I think it was to avoid flipping,or dirty ik rotations.. I'm positively not shure about any of this, and don't remeber where I read it.

:) Nenox


PS. For sure it should have been seperate posts! My bad :blush:

GrafOrlok
09-27-2003, 01:52 PM
I always do my blendshapes in a separate scene and then import them into my scene. When everything seems to be working I delete the original geometries and then you can always re-import them into your scene if you want to do adjustments.

Once you've created the blendshape node your morph target geometries become irrelevant, so if you want to do changes you'd have to delete the blendshape and then create a new node with the changed geometry.

dwalden74
09-27-2003, 03:15 PM
I don't know if that's what you refer to as a shader node

Yes, by "shader nodes" I mean any of these utility nodes. BTW, there exists more shader nodes than you see in the Maya UI when you call up the "Create Render Node" window. blendWeighted and blendTwoAttr are 2 of my personal favoriteīs.

I seem to recall someone using the Blend Colors node in conjunction with orientconstraints

I think I know what you mean. I saw a setup once that blended rotational values from two different joint chains via blendColors nodes. RGB was driving XYZ. This was interesting because the blend was never "interpolated" the way blending constraints works. Instead they were direct connections, which meant that no "flipping" would occur during the blend. This seemed a good solution. Now Maya 5 has an "interpolationType" attribute on its orientConstraints which also helps you avoid the flipping behavior. So far this has worked very well for me.

:beer:
David

Nenox
09-28-2003, 12:39 PM
Thanks guys. Just the answers I needed!

I just had a look at the Create Render Node window yesterday and by the looks of it, it could be a regular goldmine for us nonscripters / -expressionists.. :drool:

Cheers guys,
Nenox :)

danielpk
09-29-2003, 09:32 AM
Originally posted by Graf Orlok
[...], so if you want to do changes you'd have to delete the blendshape and then create a new node with the changed geometry.

Hi,

you CAN reconnect your imported targets directly to the existing blendShape node. You don't even need to import anything because the information about a target is stored in the blendShape node itself. To further shortening the process, you may want to use a script I've written. You can find it on my website under MEL Scripts->Rigging. It's called DPK_combinationSystemUI and can be used to do "combination-sculpting", the technique used to create the faical setup for Gollum and is discribed in more detail in my thread (http://cube.phlatt.net/forums/spiraloid/viewtopic.php?TopicID=634) on SpiraLoid. It also let's you edit existing targets without any "combination-sculpting" by selecting the targets you want to edit in the window, right-click and "Edit". It may not work so well if you have history on your geometry but you can try it...

Good luck

Daniel

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