Modify nHair attributes

To make nHair look more realistic, you can modify the hair system attributes to increase hair thickness and body, and add curls and shape to the hair. When you modify nHair system attributes, changes are made to all the curves in the hairSystemShape node and not individual hair curves. To modify the look of individual hairs or clumps of hair, you need to edit their follicle attributes.

In this section of the lesson, you modify various hair system attributes to make the model's hair look fuller and more realistic. Then, you add curl and stiffness to create a basic hair style.

To increase hair thickness

1. Rewind the simulation to the start frame.
2. To select the hair system, drag around the hair curves and select nHair > Convert Selection > To Hair Systems.
3. In the Attribute Editor, click the hairSystemShape1 tab.
4. In the Clump and Hair Shape section set the following:
   • Clump Width to 0.3.

     Clump Width controls the width of the hair clump from root to tip.

   • Hairs Per Clump to 10.

     Hairs Per Clump controls the number of hairs per curve (hair clump). Increasing this value increases the rendering time.

   • Sub Segments to 2.

     Sub Segments adds the specified number of points between segments/points and helps smooth the hair curves.

   
5. Play the simulation.
   

   The nHair is noticeably fuller.

   You can further modify the hair clump width by adjusting the Clump Width Scale attribute to vary the width along the hair from root to tip. For example, you can set the Clump Width Scale ramp so that the hair clumps are tapered.

6. Rewind the simulation to the start frame.
7. In the Clump Width Scale section, do the following:
   • Select the first marker in the ramp, set Selected Position to 0.026.
   • Set Selected Value to 0.86.
8. Click in the ramp to create an additional marker
9. Set the Selected Position and Selected Value for the two remaining markers to the following values:

   Marker	Selected Position	Selected Value
   2	0.63	0.74
   3	1.0	0.

   

   Continue styling the hair by adding curl to hair clumps. You can add curl to hair clumps and vary the amount of curl from the hair root to tip. For example, you can set the Clump Curl ramp so that the curl is concentrated in the middle regions of each hair, then gradually decreases at the hair tip.

To add curl to the hair clumps

1. In the Clump Curl section, click in the ramp to create additional markers then set the following marker values:

   Marker	Selected Position	Selected Value
   1	0	0.0
   2	0.25	0.75
   3	0.5	0.9
   4	1.0	0.0

   The Clump Curl ramp creates large scale curls about the clump center, adding some twist to the hair.

   
2. Play the simulation

   You can also use the Curl attribute to create curls along the direction of individual hairs.

3. Rewind the simulation to the start frame.
4. In the Displacements section, set the following:
   • Curl to 1.

     Curl sets the amount of curl displacement relative to the hair width.

   • Curl Frequency to 12.

     Curl Frequency specifies the rate of the curl. The higher the value, the more curls are added.

   
5. Play the simulation.

   After playing the nHair simulation, you can see the hair style beginning to take form, however there are several areas of hair that look too thin and patchy to be considered a realistic hair style.

   

   In the next section of the lesson, you add passive follicles to fill in the regions where the hair is thin.