Skinning a Character in 3ds Max - Part 7 - Shoulders

By
-
Login to Follow
-
Industry
  • Games
  • Design Visualization
Subject
  • Animation
  • Character
  • 2013
  • Character Animation
  • Workflow
Products
  • 3ds Max
Skill Level
  • Advanced
Duration
8 min

Skinning a Character in 3ds Max - Part 7 - Shoulders

In this tutorial, you adjust the skinning of the shoulder area. This is arguably the hardest area to adjust and you will find yourself spending a lot of time fine-tuning it. The reason is that vertices in that area are likely to be affected by more than two bones and therefore require a little more attention. However, the principles learned still apply and you simply need to be patient adjusting the solution.


Notes
  • Recorded in: 3ds Max 2013
  • This tutorial is intended for use with 3ds Max version 2013 or higher.
Transcript
00:00:02 --> 00:00:07
We come to what is arguably the hardest joint to skin properly, the shoulder joint.

00:00:08 --> 00:00:12
The reason is that this joint is articulated in many different ways.

00:00:12 --> 00:00:17
The vertices in that area often respond to three or even four bones simultaneously.

00:00:18 --> 00:00:22
The key is identifying those bones and applying the proper weights.

00:00:22 --> 00:00:30
There are no strict rules or strict values to be used. Skinning, as you have learned so far is mostly visual, and a bit instinctive.

00:00:31 --> 00:00:35
First adjust the animation length to focus on the area of interest.

00:00:36 --> 00:00:41
Most of the shoulder animation is taking place between frames 880 and 1160.

00:00:43 --> 00:00:49
Obviously the skinning at this point isn't working too well but you're about to change that.

00:00:50 --> 00:00:52
First make sure you are in the Front view.

00:00:53 --> 00:00:58
Press F3 to switch to wireframe mode, and take a look at the animation.

00:00:59 --> 00:01:03
The shoulder rotates down between frames 880 and 900.

00:01:06 --> 00:01:11
However, consider how it rotates up between frames 920 and 940.

00:01:12 --> 00:01:18
Much of the work is done by the clavicle, although the shoulder bone does rotate a bit also.

00:01:19 --> 00:01:24
In fact, there is even a slight twist of the shoulder bone, the higher it rotates.

00:01:24 --> 00:01:30
Try it out: lift your hand above your head and feel the slight twist of the shoulder bone.

00:01:31 --> 00:01:34
This is important to get the shoulder vertices to work properly.

00:01:35 --> 00:01:44
If you just rotate the shoulder and leave the clavicle untouched, this would result in bad joint animation.

00:01:48 --> 00:01:53
Before starting the skinning adjustments, notice the FK and IK bone chains.

00:01:53 --> 00:02:00
These won't be used for skinning as discussed earlier, so you might as well hide them from view at this time if you haven't done so already.

00:02:01 --> 00:02:07
The FK/IK branches for the left arm are easy to select around frame 900.

00:02:07 --> 00:02:12
The ones for the character's right arm are a bit harder to select in the viewport.

00:02:12 --> 00:02:19
Press H and select them from a list, or zoom in and double-click the respective shoulder bones to select them in the viewport.

00:02:20 --> 00:02:21
Hide the selection.

00:02:23 --> 00:02:30
Go back to a shaded viewport (F3), select the mesh and enter Edit Envelopes mode.

00:02:31 --> 00:02:33
Let's analyze the situation a little bit:

00:02:33 --> 00:02:40
At this time, most of the torso vertices are not affected by any of the clavicle or shoulder bones.

00:02:40 --> 00:02:47
This is expected as you set up the upper torso vertices to follow the upper spine bones earlier.

00:02:48 --> 00:02:55
As far as blocking out vertices, you may want to make a few last minute adjustments before proceeding.

00:03:01 --> 00:03:07
In some situations as is the case here, loop selection may not work to your advantage.

00:03:07 --> 00:03:12
So make sure you go around the scene so that the right vertices are selected.

00:03:13 --> 00:03:17
Assign these vertices to follow the shoulder Roll bone 100%.

00:03:18 --> 00:03:22
Block out any other "rebel" vertices in that area.

00:03:26 --> 00:03:28
Let's explore the clavicle area.

00:03:29 --> 00:03:35
All these vertices need to be somewhat affected by the clavicle bone, although by different amounts.

00:03:36 --> 00:03:42
The vertices further out need higher percentages than the ones closer to the middle line.

00:03:43 --> 00:03:47
Start by selecting the vertices near the bottom end of the collar.

00:03:49 --> 00:03:55
Open the Weight Tool dialog. At this point, these vertices are affected only by the Spine bone.

00:03:56 --> 00:04:04
Select the clavicle bone and weight the vertices by a small value, such as .1 or 10%.

00:04:08 --> 00:04:14
Select the next few vertices in line. You will almost certainly need to adjust the back vertices in a moment.

00:04:15 --> 00:04:18
For now, work on the front of the character.

00:04:18 --> 00:04:26
Use the Weight Tool dialog or the Weighting script to assign an amount of clavicle influence on the selected vertices.

00:04:29 --> 00:04:33
Move on to the next few vertices in line and adjust their weighting.

00:04:38 --> 00:04:46
Soon enough, you will find yourself going back and forth, adjusting vertices as a group, or almost certainly individually.

00:04:46 --> 00:04:50
This is where the weight script tool comes in handy.

00:04:51 --> 00:04:59
As you test the vertices around the shoulder area, you will discover which vertex needs to react to which bone.

00:05:35 --> 00:05:42
You will also find that some vertices, although far from the center line, need a bit of weighting from the spine bone.

00:05:42 --> 00:05:45
This helps in "grounding" them a little bit.

00:05:50 --> 00:05:55
Keep on fine-tuning the solution, occasionally glancing at the back of the character.

00:05:55 --> 00:06:00
Remember this process is fairly intuitive and requires a great deal of patience.

00:06:04 --> 00:06:09
The more experienced you become at this and the easier it gets.

00:06:56 --> 00:07:02
As you go below the arm pit, there are a few vertices that need to blend with the arm bones.

00:07:05 --> 00:07:10
It's best to blend these with the shoulder bone, and not the shoulder roll.

00:07:10 --> 00:07:17
You only need for these vertices to react to the up/down motion, not so much to the shoulder twist.

00:07:21 --> 00:07:28
Keep on fine-tuning the solution. Again, a lot of back and forth is required to get to a result that you like.

00:07:29 --> 00:07:32
Notice that you're only working on one side of the character.

00:07:32 --> 00:07:38
When you're done, you can use Mirror Skin tools to transfer vertex weights to the other side.

00:07:38 --> 00:07:43
However, since you still need to adjust the rest of the arm, hand and fingers,

00:07:44 --> 00:07:48
you may as well completely finish with one side before mirroring the data.

00:07:49 --> 00:07:52
Exit Edit Envelopes mode and save your file.
Posted By
Tags
  • 3ds Max
  • Animation
  • Character
  • 2013
  • Character Animation
  • Workflow
0 Comments
To post a comment please login or register
*Save $66 per month on Autodesk's Suggested Retail Price (SRP) when purchasing 1 year term 3ds Max or Maya subscription.