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TonyBorf
09-01-2011, 12:38 PM
In a tutorial I went through, the user used the multi-baker to create an mdd file of his characters motion. Then he cleared the project and loaded the original T-Pose character and added the mdd file to the deformation of the character using the md reader.

What is the advantages of doing this?

Thanks

RebelHill
09-01-2011, 02:18 PM
advantage is it clears out any rig, which 1, prevents you altering keys by mistake thereby screwing it up adn 2, without the rig having to calculate the scene will run faster, also saving maybe a couple seconds per frame come render time.

Disadvantage is that the transitions, or movement that IS happening between one frame and the next is perfectly linear, so if rendering motion blur on fast moving limbs, the blur wont form an arc.

I do however hear that the new multibaker has support for subframe baking of the motion which ofc helps somewhat to cleanup this issue. (havent tried it yet myself though).

Celshader
09-01-2011, 02:24 PM
In a tutorial I went through, the user used the multi-baker to create an mdd file of his characters motion. Then he cleared the project and loaded the original T-Pose character and added the mdd file to the deformation of the character using the md reader.

What is the advantages of doing this?

Thanks

I once worked at a studio that made this part of their Maya pipeline. Before handing off the character to the lighters for lighting and rendering, the character animators were expected to bake their animations on a point level through geocaching and delete the rig itself.

That way the lighters could quickly scrub through the scene without waiting for the rig to evaluate. It also reduced scene clutter, so the lighters could focus on their work instead of picking through a mess of rig-related objects.


EDIT -- RebelHill beat me to it. :D

-+-

Baking a character's animation to MDD and leaving out the rig gives a speed boost in LightWave, too. Plus, without the weight of the rig, it's possible to load multiple character meshes with multiple MDD files and still scrub through the scene at a reasonable speed.

pooby
09-01-2011, 02:51 PM
Another big advantave is that it's referencing an external file so every scene that might need that animation will always have the latest version of the animation without having to reload anything. You can have multiple versions of the object in different passes, such as volumetric light passes and a matte object etc all referring to the one file. It's a very good way of keeping a neat pipeline.

Another thing is that scene files are small and load quick.

jasonwestmas
09-01-2011, 06:36 PM
And of course point cache (mdd, xml etc.) allows the user to use one package to render and another to animate with relative ease. Of course the file management could be improved out of the box. . . but there are plugins like point oven that kinda do that for you.

Greenlaw
09-01-2011, 07:30 PM
MDD insures that deformations are identical in whatever program you use them in. Deformations using a rig may not look identical in different programs because each program handles deformations a little differently. This is important especially if you need render the character in various programs. We typically rig and animate in Maya, and .mdd insures that what we see in Maya is what we get in Lightwave when we light and render our characters.

In many cases, with .mdd you'll have smaller memory overhead, allowing you to have multiple characters moving in the same scene file. On the other hand, if the animated object has a very high point count and you're recording a long animation, the data file can be HUGE...in that case, .mdd loading and interaction can become slower than using a rig.

In Lightwave, .mdd is necessary for rendering certain FX (ClothFX for example,) on a renderfarm, and also for combining certain FX animations.

G.

TonyBorf
09-02-2011, 06:30 AM
Thanks for the replies, being new to LW I am still trying to get my head wrapped around some of these technical aspects of the program.