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JellyFire
01-13-2006, 07:09 PM
I've read (and also feel myself) that you should try and gett characters
to aprox world units, so 6 feet being 182 units (Cm's) would be the size
of a human male. But I get a problem (which I've included a picture of)
when I scale things up to around that size.

Maya seems to cap of geometry when scaling back and forth, it obviously
being too big, so when I'm creating my charcters, should I have my units
at Feet instead of CM. So my characters would now only be 6 units high.?
and what happens if I create a small hand sized object in cm mode..
Making it 4 units long,? If I imported it into a scene using Feet as it's units,
would it still be 4 units or something like 0.13 units?

Thanks to anyone who can clear this niggle up.
JellyFire.

Craiger
01-13-2006, 07:34 PM
The problem your experienceing has nothing to do with how big the geometry is, its a camera issue. You need to set the far clip plane to a higher value in order to see that much of the maya universe.

As far as real world models, why are you concerned about the size? It doesn't make any difference to how it will look in a render, and actually makes it harder to implement things like cloth, or dynamic simulations. Besides, when you start to animate this bad boy, you're going to have some crazy numbers on your keys. Imagine trying to animate two attributes, one which hovers around the 0 (like a cycling rotation of the hips in a walk) value in the graph, and one that accends (like the forward translation of your character walking) up into the thousands. Editing this in the graph editor becomes a hassle.

werd up.

M.E.L.
01-13-2006, 09:11 PM
kinda fail to see how real world coordinates screw things up... without using a real world based geometry system you completly screw up any scale that you have within a composited scene. Imagine taking the Cave Troll in LOTR and simply making him however you please, as much as you want to play with camera angles and zoom on him, you're now screwing with your footage and distorting the realism.

As far as cloth and dynamics, they perform far better at a world scale than at a micro scale.


When animating, what does real world scale have to do with your keyframes? Your control rig is going to be zeroed out regardless and you might have a few extra degrees of movement here and there. If anything this data is far easier to edit and work with as you're looking at a proper scale model and can interpret the data across your live action reference and other things.


back on topic...


keep your unit size to cm's, when you start getting into feet you begin to have rounding values unless you want to use a decimal value of 4 (plus, it's just a pain in the ass trying to look at a prop and realize that it's 0.2353ft tall). Cm's give you a nice precision when working to scale and also provide a solid grounds to base your dynamics & simulations off of.

as far as your importing goes, if you import a cm based object into a ft based environment then your object will default to being 0.13 units... not a very fun value to work with by any means. Keep it at cm's and standardize yourself to use this workflow, you'll notice it in almost every production facility you enter :)

-s

JellyFire
01-17-2006, 07:51 PM
Thanks MEL, thats what I thought, I understand what craiger is saying though, translate 80 units in z for one step or something :)

So let me just confirm this, I know I should stay in units, as good thing for small objects.
But for characters you generally get them about 10-20 units high, things like generiRig etc.
You're saying that I should build my character 183 units high for someone of 6 foot and
just sort out the camera plane issue? it seems fair for things incorperating into live action,
but is this a good workflow for a charactoon character>?

Thanks for your advice, 3D Talk is amazing for knowlege!
JellyFire

Craiger
01-17-2006, 09:25 PM
As far as cloth and dynamics, they perform far better at a world scale than at a micro scale.


When animating, what does real world scale have to do with your keyframes? Your control rig is going to be zeroed out regardless and you might have a few extra degrees of movement here and there. If anything this data is far easier to edit and work with as you're looking at a proper scale model and can interpret the data across your live action reference and other things.
-s

I just know that syphlex (spelling?) doesn't work as well at a real world scale and performed much better at a micro scale.

As far as animating, I've used both real world and micro scales, and I much prefer micro scales. Jelly fire was talking exactly about what I mean. Make a character who is 183 cm tall, and his steps/forward translation become huge values. Rotational values don't change of course, but it makes editing these two sets of keyframes together a big hassle.


werd up.

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