The Mirror Skin Weight Tool dosent work
 

Im seeing if someone can help me. I am doing the low poly man tutorial and Ive made mine a lot different more like an alien but Im still following along and Im at the part where Im rigging and applying skin weights. Im at the pants and on the right side I adjusted everything to where Im happy when all the joints bend with the poly pants. When I go to mirror skin weights for it to show up on the left side of the pants joints (L_pelvis, L_hip, L_knee, and L_ankle) I select my pants and click apply and nothing happens.

I have it as this:

Mirror Across: XY, Direction is checked for positive to negative,
Surface Association: Closet point on surface
Influence Association 1: Closet joint.

Am I doing something wrong? I tried adjusting the mirror across to any of the 3 and nothing works. Can anybody help me solve this problem?

I am using Maya 2008 on the Mac.

Make sure that the axis is set correctly.

Also, don't post the same question twice, it's not necessary.

The axis
 

How would I check to see if the axis is set correctly? Is it in the menu box when I open up the mirror skin weight tool? Im still really new to Maya and all its options.

Sorry for posting twice, I was actually about to delete this thread because I saw there was a forum link for any questions regarding the videos and posted it there.

What does the little icon in the bottom left of the viewport look like when you look at the model head on?

Like this?

Y
|
|
Z------X

icon
 

Ya thats what it looks like head on.

Im just not sure if im using the mirror skin weights correctly. The tutorial dosent use it and I read about it online so I was trying to get it to work. It worked when I did the upper arm and mirrored it perfectly.

Once I cmd-s and exit out and come back in would that cause it to not work if I tried it once it had been reopened or does that not matter?

The whole skin weights can be really tough sometimes.

To my recollection, the geometry needs to be identical to the other side. Might have to reduplicate the object over again, and try that.

Also, you should be mirroring in YZ, not XY

YZ mirror
 

It worked using the YZ method and clicking off the positive to negative.

Can I ask you one more thing? You had me mirror it with the YZ instead of the XY.
When would I use the XY method? I dont really understand how the xy, yz, or the xz works in the mirror skin weight option. Is it because the leg has joints are going down the y axis and moving on the z axis? When I did my arms it worked when using the XY.

I do understand why having the positive to negative x needed to be checked off.

But thank you for the help.

Joe

No. It defines the virtual plane the the information is flipped over.

Think of putting a plane where you want to mirror it over. In your case, it would be in the YZ, as there is no X depth to it. If you rotate this plane around, say so it's lying on the X axis, the plane you would want to mirror over would be the XY, as there is no Z depth to it.

Understand? It's a bit hard to get your head around. If you know the theory behind 3d planes from beginners calculus, you will understand a bit more.

it's something we instinctively know once hearing an explanation. it's obvious to me so my explanation might not be the best.
but i'll try explain it to you and hope i explain it well enough that you understand

in 3D space there is the x axis, y axis and z axis (you should have heard of x and y before in math class when you started high school at least.. provided they still teach that stuff when you went)

in the case of maya x points from left to right
y points from down to up
and z points back to forward

a plane is a flat surface

a coordinate for a point (vertex) is something like this: (x, y, z), where x, y, and z are real numbers (there are such things as imaginary numbers but you dont need to worry about that) and represent the space that the point is in. so a point at (0, 0, 0) is directly in the middle of the world

in the attached picture i have 3 planes
the red plane's verticies are all on the 0 coordinate of the x axis. it is on the y-z plane because all of its points have a 0 coordinate in the x.

the green plane's verticies are all on the 0 coordinate of the y axis so it's in the x-z plane.

the blue plane's verticies are all on the z coordinate of the y axis so it's in the x-y plane

in the second part of the attached image the arrows point in the positive direction.
to 'mirror' something in a x-y, y-z, or x-z plane is to make of copy of all the verticies of the object
you mirror something in the negative y-z plane then you take the object's verticies and you (for lack of better word) translate them to the other side of the y-z plane


if you don't understand what i said then that's because it's obvious to me after seeing the 3 planes and knowing which way the axis are going (and it might be to you once you know what just happened)

but i hope you get the idea of what i said...

if you don't get it then just bash the buttons away until you get the result you want (i do that most times)!

I think what he means to say, is that on the blue plane, all z coordinates are 0. Hence, the only possible values for vertices on this plane are only in the X and Y directions, therefore the XY plane.

Its starting to make sense
 

Ya I think I understand it. Ive been so use to using Flash and After Effects I have to set up my brain to use true 3d space. Thanks to everyone for helping me out on this. I think the more I use Maya the more I will understand everything.

Hello Chirone,
I am William and I like your work very much it is amazing. I also know about
multimedia and flash but I can not do like you have done. Thanks again for
sharing and if you do not mind then share more stuff here so I and other
people can learn more.

Re: The Mirror Skin Weight Tool dosent work