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globex
03-16-2009, 11:21 PM
I'm trying to switch from 3ds max to Maya and having a hard time. One thing that's really bugging me is I can't figure out how to make a symmetrical reference of my model.

In max there's 2 way to do it. Apply a Symmetry to the stack, or create a Reference duplicate of your model and mirror it.

How do I do the same thing in Maya, so that I have a mirrored reference of my model which will change as I make changes to the original side?

Thanks.

Zaru
03-16-2009, 11:41 PM
It's fairly simple in Maya. Just enter Edit->Duplicate Special Options. Set Geometry type to Instance instead of Copy, change one of scaling axes to -1 (just try which one is it in your case) and hit duplicate. You will find yourself with the mirrored part of the model that will react to any changes you make to the source one.

globex
03-16-2009, 11:52 PM
It's fairly simple in Maya. Just enter Edit->Duplicate Special Options. Set Geometry type to Instance instead of Copy, change one of scaling axes to -1 (just try which one is it in your case) and hit duplicate. You will find yourself with the mirrored part of the model that will react to any changes you make to the source one.

This is what I tried to do originally, however when I do that I get a duplicate of my model right overtop of the original (even though I've made changes to the scaling). And what's worse is that I can't even move the duplicate. It's stuck right on top of the original. Any ideas why this is happening?

I'm trying to duplicate a polygonal object - if that makes any difference. My pivot is set in the correct place and the scaling and transformations on the original object are clean.

Zaru
03-17-2009, 09:25 AM
That's odd. There's no difference whether you mirror a poly mesh or a mesh of other type. Are you sure you use a proper scaling axis? Also, maybe there are some problems with original mesh history. Have you tried deleting it before the duplicate operation?

globex
03-17-2009, 07:10 PM
- I've deleted the object's history
- I've made sure the pivot is set on the edge of the object

Why would I not be able to move the duplicate object? What could be locking its position?

Even when I set it to translate in the duplication options, it doesn't move anywhere. It's always right on top of the original.

Zaru
03-18-2009, 10:59 AM
Does this happen also in new scenes?

globex
03-18-2009, 04:25 PM
It's working now. I don't know what I did differently unfortunately.

Thanks for your help.

cppgraphics
12-24-2009, 10:53 AM
Dear folks,

Please explain the difference between Edit -> Duplicate Special Copy and Instance.

Both mean to same I guess, But whats the change internally?

Thanks in advance.

Stellios
12-24-2009, 04:43 PM
Dear folks,

Please explain the difference between Edit -> Duplicate Special Copy and Instance.

Both mean to same I guess, But whats the change internally?

Thanks in advance.

An instance is a Siamese twin that eats all the food you eat and sleeps when you sleep.

A copy is a twin that leaves after birth has his own life and ignores the family. After a while you wonder if your even related.

EightBit
12-25-2009, 05:47 AM
You might also take a look at the proxy function.
It mirrors your half model but also creates a smoothed version that you can move to the side. Both the mirrored half and the smoothed version will be updated as you refine the model.

cgbeige
12-25-2009, 02:12 PM
I use a script called kk_symmetry (get it on creativecrash) to set this up across whatever axis. It's pretty nice and joins the halves at the end. It can fail if you have done a bunch of things to the mesh but just unite them and merge overlapping vertices:

polyMergeVertex -d 0.0001 -am 1 -ch 1;

Stellios
12-25-2009, 04:49 PM
I use a script called kk_symmetry (get it on creativecrash) to set this up across whatever axis. It's pretty nice and joins the halves at the end. It can fail if you have done a bunch of things to the mesh but just unite them and merge overlapping vertices:

polyMergeVertex -d 0.0001 -am 1 -ch 1;


i found that to be kind of buggy, deleting history after symmetry and starting to rack up a couple undo-s made maya to crash and exit like clockwork for me.

Emil3d
12-25-2009, 05:58 PM
Dear folks,

Please explain the difference between Edit -> Duplicate Special Copy and Instance.

Both mean to same I guess, But whats the change internally?

Thanks in advance.
Technically speaking:
In Maya all geometry objects have a shape and transform nodes.
The transform node contains information about things like the Position, Rotation, Scale, and other attributes that you can find listed under the transform tab (node) in the Attribute Editor, Channel Box, etc. When you manipulate an object in the viewport in object selection mode, you are changing the transform attributes of the object.
The shape node contains information about things like the position of vertices, adding/deleting faces, and the attributes that are under the shape tab (node) in the Attribute Editor, Channel Box, etc. When you manipulate an object in the viewport in component selection mode, like moving a vertex, you are changing the shape attributes of the object.

A shape node cannot exist without a transform node and it is also a child of the transform node. However a transform node can exist without a child. For example you can delete the child node and the transform node will become in effect an empty group node.

When you make a Copy of an object, Maya creates a new transform and shape nodes which are identical to the original but with different names and can be altered to become different from the original.

When you make an Instance of an object, with the transform node Maya does the same as with making a Copy, it gives it a new name and the transforms can be altered differently from the original. However it doesn't create a copy of the shape node but uses the same shape node parented with this new transform node. You can compare this with having a file in a folder in your computer and then creating a new folder and putting an alias of the file in it. In Maya this effect is called an Instance. All instances have the same name and changing the name or attributes, like moving a vertex, will make the same change to all same instances. In other words, Maya uses the information from the same shape (geometry) to display or render it at different places indicated by the different transform nodes. This saves a lot of memory and makes it convenient when you want to make the same change to a number of identical objects.
Hope this helps.

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