How to Generate Hair in Blender Using Particles

Creating realistic hair in Blender is a straightforward process when using the built-in particle system. This guide provides a step-by-step walkthrough on how to set up a hair particle system, shape and groom the strands using Particle Edit mode, and adjust density and render settings to achieve a natural look for your 3D models.

Step 1: Add a Hair Particle System

To begin, you need to apply the particle system to your 3D object, which will act as the emitter (usually the scalp of a character).

1. Select your mesh in Object Mode.
2. Go to the Particle Properties tab on the right side of the screen (represented by a blue icon with three connected dots).
3. Click the + (plus) button to create a new particle system slot.
4. Change the particle type from Emitter to Hair.

Immediately, long strands of hair will appear projecting outward from the vertices of your mesh.

Step 2: Configure Basic Hair Settings

Before styling, you must adjust the core settings of the hair strands in the Particle Properties panel.

• Number: This controls the amount of parent guide hairs. Keep this number relatively low (between 100 and 1,000) for easier styling.
• Hair Length: Adjust this slider to set the starting length of the hair.
• Segments: This defines how many bend points each hair strand has. If you plan on creating curly or highly styled hair, increase this value (e.g., to 5 or 7) to prevent the strands from looking blocky.

Step 3: Groom the Hair in Particle Edit Mode

To style the hair, you must switch from Object Mode to Particle Edit mode.

1. Select your mesh and change the interaction mode from Object Mode to Particle Edit using the dropdown menu in the top-left corner of the viewport.
2. On the left side of the viewport, you will see a toolbar with various brush tools:
   • Comb: Brushes the hair in a specific direction.
   • Smooth: Straightens out bends and kinks.
   • Add: Dynamically grows new parent guide hairs.
   • Length: Scales the hair up or down.
   • Cut: Trims the hair strands.
   • Puff: Lifts the hair away from the mesh to add volume.
3. Check the Deflect Emitting box in the tool settings at the top or side of your screen. This prevents the hair from clipping through the skull mesh while you brush it.

Step 4: Increase Hair Density with Children

Instead of increasing the “Number” setting in Step 2—which can severely lag your computer—Blender uses a system called “Children” to generate high-density hair based on your styled parent hairs.

1. Go back to the Particle Properties panel.
2. Scroll down and open the Children sub-panel.
3. Select Interpolated. This generates child hairs between the parent hairs you styled.
4. Adjust the Display Amount (how many hairs you see in the viewport) and Render Amount (how many hairs appear in the final render). A Render Amount of 100 is a common starting point.
5. Use the Clumping and Roughness sliders below the Children settings to add realistic imperfections, frizz, and clumps to the hair.

Step 5: Materials and Rendering

To make the hair look realistic, you need to apply a material and set up the render engine properties.

1. Go to the Material Properties tab and create a new material. Set the surface shader to Principled Hair BSDF. This shader simulates the light scattering of real keratin.
2. Go back to the Particle Properties panel, open the Render sub-panel, and select your new hair material from the Material dropdown list.
3. Under the Hair Shape panel (still in Particle Properties), you can adjust the Diameter Root and Tip to control the thickness of the individual strands.
4. Finally, go to the Render Properties tab. Under the Hair panel, change the hair subtype from Strand to Strip for a much cleaner and more realistic 3D volume in your final render.