When you first create hair it appears sticking out normal to the surface. For a more natural look, play the hair simulation
to see the hair react to gravity and then you can set a more realistic Start position for the hair. In these steps you create
hair on a NURBS model and set a Start position after playing the simulation. You use Interactive Playback to play the simulation
while adjusting dynamic hair system attributes and see how your changes affect the simulation.
Note
Before continuing with the procedures below, make sure the End Time and Playback End Time in the Range Slider are both set
to 10000.
To create hair on a model
- Select Marion’s scalp, as shown in the image below.
- Select > and in the window, specify the following:
- Set to .
- Ensure that is turned off.
- Ensure that is turned on and set the to 26 and the to 22. These determine how many hair curves within each UV range.
- Set the to 0. No passive curves will be used in this lesson. The behavior of passive curves is interpolated between neighboring active
curves. For more information, see in the Hair guide.
- Set the to 0.5. A value of 1 represents total randomization of placement of hair curves on the surface, whereas a value of 0 represents
no randomization.
- Ensure that is turned off.
- Turn the option on. This ensures the hair curves are evenly distributed over the surface.
- Ensure that is turned on.
- Set the to 10. This sets the number of segments per hair. More segments are needed to make long hair look natural or to create complex
short hairstyles. As you increase the number of segments, you decrease the performance (speed) of the simulation.
- Set the to 10. This value is relative to the world space units.
- Click .
The hair is attached to the scalp and sticks out perpendicular to the surface. You are looking at the Current Position of the hair, which is also referred to as the “dynamic” position. Do not edit the hair curves in this view; edit only in
Start Position or RestPosition.
To play the hair simulation
- Click the Play button to play the simulation.
The hair falls due to default dynamic forces, such as gravity, which are found in the hair system attributes. However the
hair takes a while to fall, which is as a result of a high setting.
- Click the Stop button to stop the simulation when the hair is relaxed as it is in the following image.
Notice the hairs are quite stiff and stick out from the scalp instead of naturally falling closer to the scalp. To make the
hair appear less stiff you can either increase the number of Points Per Hair (segments), which increases the simulation and
render time, or you can reduce the value in the hair system’s attributes.
In the next part of the lesson you adjust dynamic settings of the hair system, including and , to achieve more naturally behaving hair.
To improve playback performance and modify dynamic settings
- In the ( + a) select the hairSystemShape1 tab and change to 2. This affects how many hairs display in the scene view, but has no effect on how much hair appears in the software render.
By reducing the , this speeds up the playback of the hair simulation.
- In the section the default value for is 0.10. Since the hair is quite stiff, reduce the value to 0.07.
- Select to play the simulation. Watch the hair begin to relax more.
- With the simulation still playing go to the section of the hairSystemShape1 tab and change the value to 2.5. Watch the hair relax even more and rest closer to the scalp, as hair does naturally.
- Click the Stop button when the hair has relaxed as in the following image.
To set the position of the hair for the start frame
- When you are playing the hair simulation, by default you are viewing the curves. To select all the curves, click any hair curve and then select .
- To set the start frame of the hair simulation to how the hair appears now, select .
- Select to view the Start curves and see that they took on the .
- Click the button to rewind to the start frame.
The position of the hair at the start frame is now relaxed.