A hairstyle, a beard, brows or lashes: a groom in Sisir, baked down to cards and handed to Unity.

Do Make a Prop first if you haven't. A hairstyle adds a second application, an alpha atlas,
a baked vertex-colour contract and a normal transfer all at once, and every one of those is easier
to learn when the export-import-prefab loop is already familiar.

One question, and it decides geometry, bones, material and budget together. Answer it before you
open anything.

→ Hair

Hair is read as silhouette and clump, never as individual hairs. So the reference that matters
is the outline from four angles and one shot of it in motion.

Get the parting and the hairline specifically. They are small, they are where the eye goes, and
a groom that is wrong there is wrong in a way no amount of card work fixes.

Assets/Source/Meshes/Character/Hair/

The SubCategory is the region (Hair, Beard, Brows, Lashes or Body), and it is what
puts the file in its folder. The style is the descriptor after it, never a SubCategory of its
own, and never left out: SM_Character_Beard_01 puts Beard in the descriptor slot and is not
checked as hair at all. MSH022 says so, and names the fix.

The .sir scene lives there too, beside the .blend. The .sir is the asset; the .blend is
where the bake happens.

→ Hair, Grooming > Where the files live, Project Folder Structure > Where does my file go?

Guides first, then density, then clumping. Style the guides until the silhouette is right at a
distance, because that is the only thing that survives becoming cards.

This is the step you are actually paid for, and it is the file you keep. Everything after it is
a bake. → Grooming > Sisir

Cluster, fit, and check the count against the tier's budget before you start fixing anything by
hand. A groom that bakes to twice its budget is re-clustered in Sisir in a minute; the same
reduction done on the cards is an afternoon that the next bake throws away.

Then look at the roots. Every card's scalp end sits against the scalp. A card that came out the
other way round hangs perfectly and animates from the tip, so it is invisible until it moves.

→ Hair Cards

One sheet for the whole set, named for the set and not for any one piece. The hair, the beard, the
brows and the lashes of one character all map into it. It is the same argument as a trim sheet on a
kit.

A card maps into its strip once and never tiles, so nothing about seamless tiling applies here.

The atlas goes in UV channel 0, the first UV layer. That is the one the bake reads, not
whichever layer is active. Roots at the top of their strip, as the rules' rootAt says.

Then tell the add-on how many strips the sheet is cut into (Atlas strips in the Hair Cards panel).
Until you do, the check for a card straddling two strips does not run, and the panel says so.

Nothing checks the sheet itself yet (its prefix, one sheet per set, its maps). TEX009 writes the
layout down and no tool reports it, so the atlas is right because you made it right.

→ Hair Cards > The atlas, Make a Texture Set

Use the add-on's groom import, not File ▸ Import. OBJ declares no units and no up-axis, so the
operator is where the convention lives. Name the Scalp Proxy in its sidebar and it runs the normal
transfer on the way in. That is the single biggest difference between hair that reads as a volume and hair
that reads as a pile of planes. It drops the file's own normals first, because Blender would keep
them as custom normals and they would pass for transferred ones.

With Join off, or when the join fails, every object gets the same treatment on its own, and the
report says how many objects any step failed on.

Keep the character's Body in the same collection, named as the Body: SM_Character_Body_01.
The flip check and the placement check measure from that mesh and nothing else; without it they say
there is nothing to measure from rather than guess. If your scalp proxy is a separate cap and you
want the flip check to measure from it, name it as a Body too: SM_Character_Body_Scalp_01.
→ Hair > Which mesh is the cards, and which is the Body

If MSH022 then says the cards are the wrong size, or not on the character, believe it: it names the
unit the file was probably written in.

If the scale came in wrong, fix it in the import, not by scaling the object. MSH002 blocks
that export anyway.

→ Grooming > What OBJ costs, and the three answers, Grooming > Normal transfer from a scalp proxy

The import runs it unless Bake Channels was unticked; Bake Hair Cards in the Hair Cards panel
runs it again. It writes root-to-tip (R) and a per-card random (G), and seeds stiffness (B)
once, at 1 (pinned), on every card, the first time. It also flags HairData for render, which is
what makes it the colour that ships. If another colour already carries the flag,
MSH022 says so and offers Flag.

Do not hand-paint R or G. They are arithmetic on geometry, they are re-baked every time the
cards are, and a hand-painted value is a value that disagrees with the mesh the moment a card moves.

Stiffness is the exception worth knowing: it is a decision, not a measurement, so nothing can
bake it. A braid that should not swing is told so afterwards: select any part of its cards in
Edit Mode and press Mark Hair Stiffness. Every card the selection touches is set whole. A
re-bake never changes B unless Reset Stiffness is ticked on it, which is the one way to lose
it. → Hair Cards > Why B is stiffness and not length

MSH022 runs in the Asset Rules panel and on export. Set the Card budget first if this is a
hero or background character. Everything else defaults to standard.

Leave Edit Mode first. A card mesh being edited is not measured at all, and the Hair Cards panel says
so rather than reporting findings that would vanish when you tab out.

Then press Measure Hair Overdraw in the Hair Cards panel. It is the one number that says what
the hair costs, and nothing measures it for you, not live and not on export, because it takes seconds of
work on a full head. The limit is on the average a view ray crosses; the panel shows the worst
spot beside it. → Hair > Overdraw is an average, and it is measured on request

Most findings come with a button. A missing, short, folded or out-of-date root-to-tip is fixed by
Bake, which runs in Fix All and never touches the stiffness you authored. Every finding that
names cards has Select, which opens the mesh on them. If you have just added or deleted cards,
let the panel catch up first, because card numbers move when cards do. A flipped card has Flip.
Press it yourself. It is kept out of Fix All on purpose.

A Mirror or any other modifier that changes the card count holds back every card finding on that
mesh until it is applied: apply it, then bake.

It is a warning, like every new rule, so it will not stop you, and the flipped-card finding is
the one to actually read. → Hair Cards > What the checks can and cannot see,
Check Your Work > When a rule is wrong

Then run Workspace Check on the project folder like anything else. → Check Your Work

Same as a prop from here: export with the add-on to
Assets/Exported/Meshes/Character/Hair/, build the material and prefab in Unity, commit with the
.meta files. → Make a Prop > 10. Export onwards, Grooming > Export through the add-on

The add-on's export is what puts the render-flagged attribute (HairData, once baked) first in
the .fbx, where Unity reads it. Blender's own
exporter does not, and the hair data can arrive behind another colour that Unity reads instead.
→ Hair Cards > The render flag decides which attribute ships

The bone chain and the physics go on the prefab. What the material does with the baked channels
is the half of the contract this vault does not describe yet. Read the gap before you guess at it.
→ Hair Motion > The other half of this contract