Usage

Step 1: Create hair_sprout Vertex Group

In this example, we’re going to have the character "sprout" hair from (basically) a specific vertex (kind of the inverse of the male bald spot), then get the hair ready to be combed into a usable haircut. Essentially, we’re going to cover as much of the head as possible at first, and then later we’ll worry about any additional hair systems which should be added.

Step 2: Move 3D Cursor to Sprout Vertex

In Edit Mode, select the vertex from which all the hair should sprout, and then add it as the only vertex in a new vertex group called "hair_sprout".

In Edit Mode, select the vertex from which all the hair should sprout, and then do a 3D Cursor to Selected:

Step 3: Add hair_sprout Particle System

Now add a particle system with my Create Hair System add-on:

• Object: body
• Vertex Group: hair_sprout
• Type: Hair
• Material: hair
• Length: M
• Thickness: M
• Segments/Render Path Steps: 10
• Parent Particle Amount: 360
• Child Display/Render Particle Amount: 25
• Emit From: Vertices
• Hair Dynamics: Unchecked

Click the "Create Hair System" button to create the particle system.

Here’s the most important thing at this point (and it’s not demonstrated in the above image): GET THE HAIR TO BE AT ROUGHLY THE CORRECT LENGTH. Basically, get it to be the longest it will need to be when it’s coming out of the hair_sprout vertex. So take one hair and comb it down. If it’s too long, either redo the particle system or delete the particle edit and manually change the length.

Yes, you can cut the hair later...but if you have to cut too much off later on, the keys will all bunch up along the ends of the strands and you’ll also get bald spots near the top because there aren’t enough keys there.

Step 4: Move Hair Roots to Same Location

The Create Hair System add-on always creates a hair system that emits from a face, not a vertex. (This is because is a Blender bug where if you start combing hairs that emit from a vertex and then go to render those hairs – not view the 3D Viewport in Render mode, but ACTUALLY render the image – the hairs will be in the opposite direction on the Z axis.)

Uncheck Preserve Root Positions and move all of the hairs to the roughly the same spot on the head – basically, to where the 3D cursor is.

Make sure to check the hairs from every angle when you’re done.

When you’re done, make sure to CHECK Preserve Root Positions!

Step 5: Comb Hair Straight Up

Now comb the hair straight up, using my Mouse Axis Lock (Ctrl+Alt+U) script to make sure the hair is EXACTLY straight up.

Be sure to view it from all angles; it’s possible there may be a straggler or two that didn’t get brushed up.

Step 6: Automatically Comb the Hair into Helicopter Blades

Make absolutely sure Preserve Strand Lengths and Preserve Root Positions are CHECKED!

In Particle Edit Mode, select the Comb tool. Make the radius HUGE. Set the Strength to 1.000.

Make sure Deflect Emitter is checked.

Set the Deflect Emitter Distance to 0.200.

In the Comb Utilities add-on, click “Move Camera to 3D Cursor XY”.

Back out far enough so that the comb tool will be able to comb the hairs the whole way out.

In the Comb Utilities add-on, click Automatically Comb Helicopter Hair.

Follow the instructions. (Basically, get your cursor in the right place before pressing Alt+Y to click Yes on the initial startup dialog box.)

Wait 38 minutes or so for the hair to be combed automatically. Obviously, don’t touch the computer while it’s combing the hair.

Step 7: Clean Up the Helicopter Blades

If the script missed some helicopter hair blades, fix them manually. You don’t have to go crazy making the helicopter hair blades perfect; you just don’t want big obvious gaps in the helicopter hair.

Step 8: Comb it Straight Down

Now we need to comb this hair down and over the face. The quickest and most reliable way to do this is as follows:

1. Select the outer-most ring. You can do this by going to Select → Tips.

2. Go to Front Orthographic view.
3. Make sure Toggle X-Ray is ON.
4. Select the Comb tool. Make the comb really big, so big that it covers the entire helicopter hair when it’s over the hair sprout.
5. Place the comb above the hair sprout. Press Ctrl+Alt+U to engage the Restrict Mouse Axis for Up/Down.
6. Comb the selected keys down as far as they will go. It will take multiple mouse strokes down to do this.

7. Press Ctrl+Numpad Plus to select more particles going inward.

8. Go back to Step 6 within this section and repeat until most of the head is covered properly. Make sure not to take things down so far that particles are going into the head.

Step 9: Comb the Rest Down Manually

Once the head is in a state like this, where it is more or less a lampshade…

...manually comb down the parts that are puffed out too big so that you get a nice even Cousin It:

Step 10: Do the rest!

Now that you have a fully covered human head full of hair, use Blender's tools to trim and brush the hair appropriately. Add additional hair systems as needed.