Understanding skin weight painting

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The main way to adjust the waiting is to interactively paint them,

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which is much easier and a lot quicker

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to open the paint whites tool,

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just go to the rigging shelf and click on this button here.

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So here we have a list of all the joints that are affecting this model.

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If you select one, you'll see a gray scale area appear.

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This is that joint's area of influence.

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If we scroll down, we will see those twist joints we added manually.

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You will also see the padlock next to them is yellow indicating these are locked,

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which is fine.

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If you remember,

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we locked the weights when we added these to

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stop them influencing the rest of the model's weights.

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So we just need to go through and unlock these. Now,

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just click on the icon to do this

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and let's find the rest. While we are here

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at the moment, the joints are sorted according to the hierarchy,

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but you can change this up here.

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So we can see them alphabetically

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hierarchy

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or just flat.

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What we can also do is filter the list.

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So let's say we just wanted to work on the twist joints

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we can input twist here and it will just show us the joints with twist in the name

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down here. We can choose what mode we want to work in.

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Paint

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select

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or paint select.

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I rarely use anything but paint here.

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Next, we have the main area where the paint tools are.

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First is the paint operation area.

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So you can dictate how you want the strokes to affect the weights.

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Replace will simply swap the current weight value with the one you have specified.

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Add will gradually build up an area.

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So you can continually add a value to it.

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Scale will simply scale the values. But again, I never really use this

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finally smooth,

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will gently blend the weights for you to soften and smooth an area out.

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Next, you have your brush types which range from soft to hard

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normalize weights. We discussed this before,

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but there are very similar options here.

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Next, we have the opacity and value sliders which work hand in hand with each other.

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Opacity is basically a percentage of the value slider.

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So value is the main weight value

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and opacity will paint either all or part of that.

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If value is set to 0.5

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opacity will never be able to paint above that value.

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This works well as it allows you to gradually adjust the weights,

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it gives you more control.

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Let me show you

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a quick tip is you can also select which joint to work on in the main view,

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just right click on the joint and go to select influence.

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So with opacity and value both set to one,

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we get solid white.

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So these vertices are being influenced by the Pelvis joint 100%.

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If I reduce the opacity,

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you see we can instead gradually add those weight values.

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If I instead set opacity to one

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and then drop value,

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no matter how much we paint, we won't be able to go over

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the value amount.

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We can still drop the opacity and gradually add the weights,

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but they won't go over this value of 0.1456.

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So those are the main painting tools.

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Oh yes. One other option is flood.

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This will simply fill the whole model with that value.

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So now the model is influenced fully by the Pelvis joint

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down here. We can control how the influence is represented.

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Personally, I prefer to work with just gray scale,

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but you can enable color feedback if that works best for you

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with. This enabled red is the higher weight value.

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Here. We have options to adjust the paint stroke.

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You can also use a graphics tablet to control the opacity.

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If you want a more interactive painting experience,

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also you have various display options here.

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So if we didn't want to see the joints through the model, we could disable this.

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I think that's the main options covered the ones I use. Anyway,

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obviously, there's so much more to this tool.

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But for this project, those options are fine.

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Before we end,

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I also want to show you that you don't always

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have to paint the weights on the whole model.

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Let's select these vertices

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here.

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Now, if I go back to the paint whites tool

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with opacity and value set to one.

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If I paint, now the area I am affecting is restricted to just those vertices.

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You see I can paint up here but nothing happens.

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I can also use flood

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and it will just update the selection.

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This can be really useful for blocking in weights quickly

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or when you are focusing on just one area.