View Full Version : Does size matter?

01 January 2010, 11:46 PM
I have a character that I modeled and rigged to use in a short animation. Well, it is about 8 minutes long, so really it feels like a feature length movie with all of the work that I have to do. Anyways, I was wondering if size/scale matters when modeling a character and sets? This is how much room my character takes up on the grid:

One of my teachers told me it is a bad idea to scaled down bones, and I would rather not go through all the work of rigging him all over again and repainting the skin weights, so my question is: is it alright to built my sets based on the size of my character now? I'm going to need very expansive outside shots with forests, buildings, etc. Do really large sets slow down the computer or slow up rendering? Are there any benefits of modeling everything smaller or bigger? I know these questions are really basic but I can't find the answers anywhere. Thanks in advance.

01 January 2010, 12:05 AM
Typically I use 1 maya unit = 1 inch. It is good to have a standard reference to go to so you are not making characters that are bigger than your sets and so on... especially if your splitting up the work. Scaling a character is something that happens in animation all the time to "cheat" the shot, but this usually means that things that don't scale w/ the rig (cloth sims, hair or procedural textures) need special work done to accomidate this. Also, there is a down side to making things too small... this is percision errors. If your character is 1 maya unit tall (I'm exaggerating to make a point), this means that anything that is a subcomponent will be a decimal. Maya will only go out so many decimal places (I think 6) before it starts to truncate. This is usually not noticed on larger characters since the value is so small, but if you are working at a really small scale, this can become quite noticable.
Hope it helps.

01 January 2010, 12:08 AM
No idea how things work in Maya, but size does matter in 3ds max when dealing with cloth or any other simulations or IES lights for instance.

While you not always have to deal with that stuff I think it's a good habit to keep that in mind and work in real world scale anyway.

01 January 2010, 12:35 AM
scrimski and dragon,
Thank you both for the replies. Also, I forgot to specify that I am working in Maya. Here is another screenshot:

So my character is 5 maya units tall, or as you (dragon) would put it 5 inches tall going by the way you scale things. Thank you for pointing out that scaling things too small will cause precision problems, something I never thought of but makes a lot of sense. I'm going to have a lot of animals and some bugs in this short, so they will all be scaled proportionately to my bear character. I'm thinking I should double my characters size, since I need characters that will be as big as his paw, or smaller (which is about 1 maya unit squared.) Does doubling the characters size make sense, or should I make him even bigger?

01 January 2010, 12:24 PM
Just a couple of points to add, while you should be ok for this project you should get in to the habit of modelling to a 'real world' scale, basically set your units scale prior to beginning and model everything the correct size. This will become more important in the future should you find yourself working in this industry and getting in to the habit while you are new to it is easier than breaking the habit of not doing it later on.
a few examples of why this is important could be:
1. when working across departments, if the character modellers and the background artists and the rigid body team and the animators etc are all using different scales then some poor fool is going to have a nightmare resizing everything prior to putting it all together.
2. Lighting. As Scrimski touched on, when you get a bit more advanced and want to start producing photo realistic scenes using photometric lights, the lights you use are based on real world units (candelas etc..) if your scene is scaled incorrectly you are creating one serious headache for your self.

Hope this helps.

01 January 2010, 02:01 AM
Thanks for the tips hypnocookie, I'll keep everything real world scale from now on, I had no idea that scale could affect lighting and so on.

01 January 2010, 06:39 AM
ALL your characters should have a global scale, your teacher is wrong to tell you that-- if you're working in a studio and your director says "hmm, could you make the girl 10% smaller?" and you haven't rigged it to do that , all you could do is stare blankly and look dumb.

Making a global scale isn't hard!

For basic rigs, some complex rigs, that are far beyond my fathoming, I wouldn't know how to... but for basic rigs it's usually a matter of making a global control, freeze transforms, grouping the control objects, the skeleton, the extras (ik handles, clusters, spline ik curves), then putting a parent + scale constraint (with maintain offset ON) on the control grp, a scale + parent (i think you use a parent here..) on the extras, and just a scale on the skeleton.

If you use stretchy limbs you might have to include it in your expression somehow.

Hope this helps.

01 January 2010, 09:30 AM
No probs Bmiles, hope the project goes well

01 January 2010, 10:29 PM
The way I was taught to rig was to have all of the bones parented to a global control on the ground (the cross made up of four arrows for example). I've never used a scale constraint before, are you sure that will keep all of the bones intact? I heard scaling bones can make them get all crazy. I'll have to try it out later when I'm in front of Maya. Thanks for the help Virtualistic.

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