The Muscle Paint window provides a number of different weight types to paint for the various deformation features. In addition to painting weights or applying default weights, you can also load, save, mirror, transfer, and prune weights.

To paint weights

1. Select the object you want to paint weights for.

   The object must have a Muscle deformer applied. You can also select points of the object, which allows the painting to be effectively ‘masked’ so that you only paint on the selected points.

2. Select Muscle > Paint Muscle Weights from the main menu bar.

   The Muscle paint weights feature draws a colored mesh similar to Maya painting if you are using a polygon mesh. For NURBS and subdivision surfaces, colored points display instead.

   The Muscle Paint window appears, and you can start painting.

   NoteYou must have Locators set to on in the Show menu of your scene view to see skin weight painting colors.
3. In the Weights drop-down, select the type of weight you want to paint. The default is Sticky but you can also select Sliding, Direction or any of the other weights.
   TipIf you are painting Sticky weights for the first time, select your base or root bone, set the Weight value to 1.0, and click Set Weight/Flood.

   This floods the bone or object to have 100% of all the weight. If you do not do this initially, points may move incorrectly as you paint because they may not have a truly normalized weight of 1.0, even though the Normalize button is on.

4. Select the muscle or bone object, and begin painting on the mesh.
   TipHold down the b key and drag left and right in the scene view to change the size of the brush.
5. (Optional) Test the results of your weighting by animating your rig, and tweak the weighting as necessary.
6. (Optional) Select a different weight type in the Weights drop-down menu and repeat the previous steps for the other weight types (Sliding, Relax, Wrinkle, Jiggle, Cycle, Rest weights and so on).
   TipAs you switch between weight types, you can disable each type to improve speed. For example, you may want to disable Sliding weights as you work with Relax weights.

   You can also disable the deformer as you paint weights for faster interaction.

   When you are finished with the other weight types, you can use the Smooth weights to fix any problems.

To set point weights on each point or multiple points

1. In the Muscle Paint window, turn off the Paint option.

   You can now directly select points on the mesh, and set their weights with the slider. The average weight for selected points is shown in the Weight field when points are selected and Live Update is on.

   When finished, if you want to return to Paint mode, you can deselect any currently selected points, then turn the Paint option back on to return to painting the entire mesh. Alternatively, if you leave some points selected, only those points are paintable, and you have effectively ‘masked’ the painting to only the selected points.