Making Your First Model Part 17
Weighting the Model

Welcome to another installment of Angsty Teen Mae Struggles Against PMXe. Scroll to the bottom for an actual, informative guide to weighting.

We’re going to do this the old fashioned way.

Every time I bring up weights with Bandages, he tells me to do it in Blender. And I always let out the sound of a deflating balloon because I’m a big dummy! I don’t understand how to do it now matter how many tutorials I read! (note, I understand how to do it and I’ve tried it. My issue is just that I prefer seeing each little dot instead of just seeing a nice, smooth surface.)

So, we’re going to do this the quickest, easiest, and big dummy-ist ways possible. Is it right? Maybe. Is it graceful? Nope!

I learned this method from a hair physics tutorial. It’s really simple – paint everything below the bone at 100% strength. Then paint everything below the next bone at 100% strength. PMX will just deal with it.

So, to open up the “Weight” tab, find the option on the toolbar called “Wght”.

To switch between bones, just select a bone in the panel that we had just been using to make the bones.

Now, let’s start with her head. We want to weight her entire braid to her head until we can add physics to it. Why? Because otherwise it won’t move! Her dress and skin will get in the way, so mask it.

I had already started making a “Speed Weight” video and got around her shoulders when I got distracted and realized that the pressure of recording was making it harder than it should have been! So that’s why her eyes are blue. I had weighted them them to the eye bone already. Regardless, let’s move on!

We can test to see if it works in “Transform View”. You can open “Transform View” either by going to “View > Transform View” or by pressing F9.

Whoo! It worked! You can tell it worked because all of her head and hair is moving as one unit. Not a single part is stuck!

. . .

What?!

Ok, let me see. It must be a problem with the IK.

I found a problem with the ankle being parented by nothing . . . I fixed that . . .

So Basically . . .

When you mirror an IK bone, its index does not get mirrored. That means that even though everything looks ok at first glance in the bone panel, it’s not. Especially since 右 and 左 look so similar!

Why is her knee doing that?!

Oh . . . ! I got it!

I took a deep breath and checked my dA messages. I read through an article I was linked to and thought . . . And thought . . . And then it hit me! What if the targets weren’t mirrored either?! One of them was . . . and one of them wasn’t. I fixed it . . . And her bones are fixed! HURRAH!

Ok, back to weighting.

So, remember how I told you that mirroring the weights was going to decrease our workload? Yeah . . .

Let’s do this by hand.

STILL?!

Her hand wanted to feel the floor.

Seeing it, I can automatically think that somehow, one of her arm bones is parented by something it shouldn’t be parented to.

It was. It was parented by the invisible bone that the eye bone is connected to. 

Changing the parent from ‘Eye-Sen’ to Upper Body worked!

Now, for the knee that kept spazzing out . . . I just realized that I never limited the angle after replacing the incorrect bone in the index. Whoops!

Before we move on, I want to say one thing.

For the bones and weights . . . It actually would have been faster if I never mirrored them. If I had known what it would do to my IK bones, I would have had everything done pretty quickly on the bone front. But I had no clue! And as far as mirroring the weights . . . heh . . . that didn’t work out.

By the way, have you ever confused 上 and 下 and spend way too long trying to figure out why it isn’t working as it should? Yep. MMD is hard!

[17_011.png , alt text “Model moved away from Axis in Transform View”]

So, now, I can move her off of the axis and nothing sticks to it. Everything is weighted to something, and maybe that’s all I can hope for as an MMD n00b!

Hey! Remember how I said scroll to the bottom
for the tutorial on weighting?
Well . . . Here’s the bottom!

So, I made this “Egypt-Inspired” statue thing.

Let me add some bones so we can weight it.

Along with adding bones, I took it into Blender to give it hair . . . As this is a pretty big part of the tutorial!

Alright. Since this is “a goof”, there was no real reason to give the bones the proper names . . . But I did! So let’s start by weighting the upper body.

If you paint a vertex with 100% strength, for the arm, then paint it with 100% strength for the elbow . . . What happens?

You have a vertex with 100% strength on the elbow.

We can use that a bit to our advantage. The first weight we put down will get devoured by the appropriate part eventually!

So, go to “Wght” to open the Weight window.

In the bone panel, choose the bone you want to paint . . . Then press start.

[17_014.png , alt text “Bust with no weight values”]

This is what it looks like with no weights assigned. As we’re painting the upper body… Well, let’s paint the upper body!

I keep it set to 100% . . . mostly because no one has slapped my wrist quite yet! 

Yikes! That’s really wrong! But like I said earlier, it won’t be any issue to fix it by just being more careful for the rest of the bones . . .

Let’s draw the neck on. It’ll look very similar to the previous picture, so I’ll save you the boredom.

But I will show you what happened to the Upper Body weight paints after painting the neck!

Instead of being black to say that they were never painted, the vertices that were gobbled up by the neck are blue for 0%.

Next in line is the head. Now . . . Without physics, what does hair ideally do? It ideally moves with your head!

PMX probably has a mode that won’t allow you to paint through a material . . . But instead of finding that, we’re going to use masking to first mask the body to weight paint all of the hair to the head quickly . . . Then we’re going to mask the hair so that none of the weight paint from the arms gets onto it!

Everything but hair masked

And yes . . . I know I didn’t name my materials! I was just in such a hurry!

Now, we’ll paint the hair until it’s 100% red. After that, we’ll mask it off so that we can’t see it or affect it.

With the hair out of the way, it’s on to arms.

Now, I found an image on dA that said that at joints, you should paint at less than 100%. However, it made no sense to me. I’m going to try on one arm painting my harsh, always 100% way, and the other way with lightly dusting the joints with 25% from the adjacent bone.

I didn’t grab any screenshots of doing the arms because it’s actually hard to see what’s going on with that material . . . I am a dingbat!

But Now, this model has achieved the number one goal of weighting . . . Not leaving artifacts when it is moved around!

Bust moved from Axis with no Artifacts

For the giggles, let’s add hair physics. That will be much easier to see!

Weighting the hair bones to the model

I’m glad that this wasn’t a physics tutorial . . . Because when the hair twitched around madly, I just threw random numbers at all of the parameters until something stuck!

Now that we have that out of the way . . .

I recorded the model dancing in MMD, and I realized something.

That person who said that joints should be painted at like 75% was right! On the left side, we have the joints painted so that both bones have a little control over it. Look how nice and smooth those arm movements are!

And on the right . . . It’s a little jagged. But regardless, I hope this was an actual, informative tutorial on weighting.

Though on second watch . . . Perhaps I’m imagining things and there’s no noticeable difference!

What comes after weighting… I’m guessing physics!

Check back next time when we cover one of the scariest parts of MMD for n00bs!