Rigging- Weight Painting

I started weight painting the model I have been rigging for the past week. I followed the Academy Phoenix series' tutorial to understand the basics of weight painting.

As I started working independently from the tutorial after the basics, I will divide the post into two sections-

1. Basics of weight painting

2. Weight painting before & after

1. Basics of weight painting

- Weight painting is a process in which we control each joint's influence on the model's polygons. You can control the intensity, and range of influence per each polygon.

- The tutorial explained two methods of controlling weight. One used the component editor, and the other directly painted the weights on the bound skin.

- The component editor method is useful for excluding certain vertices from the influence of certain joints. To use the editor, select the vertices you want to control. For example, I will select the vertices on the inner thigh to prevent them from being dragged when the opposite leg is moving.

- Then, go to 'Windows'->' General Editors'->' Component editor' and open the window.

- The column on the left represents the vertices that are selected, and the row on the top represents the joints that are influencing the vertices. In this case, we want the polygons on the thigh to be not influenced by joints that are irrelevant to the movement such as the middle finger joint, right hip joint, and right knee joint. Drag & select all the vertices under the row you want to change, then type '0'. Press enter, and repeat with other unwanted joints.

- You can check the results here, as the inner thigh is no longer stretched when the other leg is moving.

- For more detailed controls, weight painting would be a better approach. Go to 'Skin' -> 'Paint Skin Weights' and click the option box.

- On the upper section of the window, you can see the list of joints and the hierarchy we set earlier in the process. You can change the joint influence and see it on the main screen by selecting each joint.

- The lighter the color is, it means that the influence is stronger. This is represented as values closer to '1'. And the darker the color is, the more the influence is. If the value is close to '0', it means that there is zero influence on each polygon from the selected joint.

- You can control the brush modes on this part of the window.

- Tip: It is easier to see the effect of the painted weights if you paint while the joint is manipulated. The effect updates in real-time as you paint them, so you can get the shape you desire.

- After finishing weight painting, you can mirror the data to the other side by pressing 'Mirror Skin Weights' under 'Skin'.

2. Weight painting before & after

- There were various points of the rigged model that were moving unnaturally. I had to adjust almost all joints or at least, smooth the influence of every joint of the model.

- These are a couple of examples of how weight painting changed the way the model moves.

(They're not perfect- as in this stage, I am constantly trying to improve the weight painting bits by bits. There seem to be some restrictions due to the low resolution and the topology flow of the model.)

Before following the next tutorial, which is blending shapes for facial expressions and such, I plan to try rigging another humanoid model with better topology and a detailed face model.