tts-voice-creator-clone-and-design-2/architecture/character-visual-identity.md

# SOP — Character visual identity and appearance forms

Status: implemented. Covers how a character's avatar and concept (reference) sheet stay the same
person, and how one character holds several appearances ("forms") without splitting into several
characters or voices.

## Single source of truth

* Appearance facts come from the sheet's `physical`, `clothing`, `age_estimate`, `race_species`,
  `gender`, `title`, `profession`, `archetype` (and the user overrides `visual_appearance`,
  `visual_species`, `visual_costume`). Both prompts are built by
  `_character_visual_facts` in `routes/conversation.py`; the active form is overlaid first
  (`_character_form_sheet`, which never lets a form change its own `id`/`name`).
* `image_prompt` (portrait) and `concept_art_prompt` (reference sheet) are **deterministic** —
  built server-side from those facts with fixed camera/lighting/period text. Sheet extraction no
  longer asks the LLM to write `image_prompt` (it drifted from the concept sheet); the prompt is
  generated right after extraction by `csAutoGenerateExternalPrompts`, and again before any
  avatar-only or per-form generation. A hand-edited prompt (`*_user_edited`) is never overwritten.
* Only the two prompts describe an appearance. `voice_design_prompt` and the SillyTavern prompt
  belong to the character as a whole, so they always live on the base sheet.

## Stale detection

`_character_identity_fingerprint` (server) and `_libIdentityFingerprint` (browser) hash the same
field list; a test runs the browser code in Node and compares, including list values and non-BMP
characters. The three `visual_*` overrides are appended only when set, so pairs made before they
existed keep a valid fingerprint. A pair needs review when its prompt version is not current, its
fingerprint is missing or differs, or `identity_consistent` is false. Regenerating **only** the
avatar or **only** the reference image sets `identity_consistent = false` on an existing pair,
because a lone regeneration produces a new face.

## Where the data lives

| | base appearance | a form |
|---|---|---|
| profile image | record `image` | `form.image` |
| reference image, version, fingerprint, digests, `identity_consistent` | `sheet.*` | `form.*` |
| Physical / Clothing text | `sheet.physical/clothing` | `form.physical/clothing` |

All visual results are written through one function (`_libSaveCharacterVisual`), which re-reads the
stored record, writes to the active form or the base, and saves. (It used to write the base
reference image to the record root, and the consistent-pair generator kept it in memory only, so a
base pair lost its reference image and metadata on reload.)

`GET /api/characters/visual-pair-review` checks the base pair and every form that has images, each
against its own metadata and its own fingerprint, and reports form pairs under the form name.

## Forms (max 8 per character, enforced in `core/validation.py`)

Add (starts as a copy of the base Physical/Clothing; only non-empty keys are stored because an
empty key would blank the base value when overlaid), rename (unique, ≤160 chars), delete (confirm;
the character, its voice and the base look stay), show, and generate matched images for one form or
for all forms. Generation rebuilds that form's prompts first (unless hand-edited), saves the pair on
that form, then restores whichever appearance was active. Editing Physical/Clothing while a form is
active changes only that form.


## Image prompt hygiene and the turnaround (1.34.x)

* **Setting.** Prompts describe the books as *The Dark Eye* high-fantasy medieval dress (about 900-1300 AD: wool and linen tunics, belted robes, leather, mail where the sheet names it). The earlier "early Renaissance 1420-1500" wording pulled uniforms, coats, hats and boots that read as musketeer/cowboy/wartime.
* **Wording.** Extracted costume text is rewritten at prompt time (`_period_wording`: Uniform, Weste, Hut, Sporen, Jacke, Schal … become surcoat, jerkin, hood, boots, tunic …). Stored sheets are not changed.
* **Injuries and dirt.** `_strip_injury_clauses` removes clauses about blood, wounds, bandages, burns, limping, torn clothes, soot and dirt from appearance, costume and the story moment; the rest of the sentence stays. The portrait baseline asks for clean skin and garments.
* **Variety.** Characters with armour or weapons get an individual garment cut and colour scheme (`_character_design_variation`, stable per name; colours the sheet names win) instead of one shared list.
* **The turnaround stays one T2I triptych.** Drawing front/side/rear one by one with the edit model was tried (2026-09-20) and reverted the next day: it returned three near-identical front views, mixed rendering styles between panels, cropped bodies, and copied the wireframe pose guide into the costume — exactly the failure the triptych was introduced to fix. The portrait/sheet face mismatch is still open and needs a different approach.
* **Props** get an object-only period sentence, so a tile no longer turns into a portrait of the character.
* Older saved prompts are cleaned the same way at render time. Existing image pairs are unchanged until regenerated.


## Automatic image check (`POST /api/character-image-check`)

A vision model reports **only what it sees** — figure count, the view of each figure left to right,
whether every head and foot is in frame, whether the figures are the same person, apparent gender,
ear shape (pointed/round/hidden), wounds, and background (plain/scenery). The expected values come from
the character sheet and the comparison happens in code (`core/character_image_check.py`). Asking a model
"is this a woman, as required?" invites agreement; asking "what gender is this?" does not, and the
expected gender is never revealed in the question.

* Kinds: `portrait`, `turnaround`, `scene`, `same_person` (profile vs. a sheet figure).
* **Fail-safe:** an unreachable checker, an unreadable answer, or a missing observation is a failure,
  never a pass. An unreadable answer is returned verbatim (truncated) so it can be diagnosed.
* Thinking is switched off: a reasoning model spent the whole budget deliberating over a confusing image
  and returned nothing.
* **Model:** the active LLM by default (`llm_model`), overridable with the `image_check_model` setting.
  The model already loaded reads images, so a check never makes llama-swap unload it for a separate
  vision model on a GPU with no room for both.

**Calibration (2026-09-21)** on seven panels whose defects were known (three front views, elf ears on a
human, a wireframe rendered as a figure, cut-off feet, a man where the sheet says woman, a forest behind a
studio portrait, and one correct same-person pair), run twice:

| model | correct | wrong | unreadable | per check |
|---|---|---|---|---|
| local Qwen3.8-27B (`default`) | 14/14 | 0 | 0 | ~4 s |
| Ling 3.0 Flash VL (`vision`, free, OpenRouter) | 8/14 | 0 | 6 | ~17 s |

Ling never judged wrongly but on every turnaround ignored the JSON-only instruction and answered in prose.
It also has free-tier rate limits and sends the images to a third party.


## Generation with checks and retries (face from the profile)

The generation job (`POST /api/character-generate-consistent-images`) now runs:

1. **Identity image** (text-to-image, full body). The profile picture is cut from it. **Portrait check**
   on exactly that crop (one person, gender, ears, wounds, plain background). On failure: a new seed,
   up to `image_check_max_attempts` (default 3), keeping the attempt with the fewest faults.
2. **Sheet** (turnaround triptych + story moment + props, one ComfyUI run). The profile's face is then
   transferred with **ReActor** (`inswapper_128`, CodeFormer 0.5 restore): turnaround faces left to right
   (front and side; the rear has none), and in the story panel only the *largest* face — the character in
   the foreground, not an extra. **Checks:** turnaround, story panel, and same-person (profile vs. the front
   view). Gender is judged *after* the face transfer, on what a viewer actually sees. Retried the same way.
3. The result carries `image_check` = `{verified, passed, attempts, failures[], checks{}}`, saved on the
   sheet and shown on the character page: verified with no faults / faults still found (listed) / not
   verified.

**If the checker itself is unavailable, retries stop at once** and the pair is marked *not verified*:
re-rolling images cannot fix a missing checker, and would burn up to three renders per character.

Why face transfer and not rendering the views from the portrait: the edit model keeps the source pose
(three front views, the pose guide copied into the costume — tried and reverted 2026-09-21). The
text-to-image triptych gets the poses right; swapping only the face afterwards fixes the identity.

Settings: `image_check_enabled` (default on), `image_check_max_attempts` (1–5, default 3),
`image_check_model` (default: the active LLM).


## The turnaround prompt is short and framing-first (2026-09-21)

Measured with turnaround-only renders scored by the image check (`scratchpad feet_experiment.py`):

| turnaround prompt | full body, head to shoes | plain backdrop |
|---|---|---|
| long compact prompt (~3 000 chars, framing rules mid-prompt), 1536x1024 | 0/5 | 2/5 |
| same, taller 1536x1280 canvas | 2/5 | 0/5 |
| same + "visible floor, contact shadow" wording | 0/5 | — |
| **short, framing first (~770 chars)**, 1536x1024 and 1536x1280 | **10/10** | **10/10** |
| the app's new prompt on Karyla, Darrag, Eolan (4 seeds each, after the fixes below) | **12/12** | **12/12** |

The 4-step Qwen-Image model follows the start of a prompt and loses the tail, so wording changes inside the
long prompt did nothing. The prompt now opens with the framing (three full-body views side by side,
head to soles, empty space above and below, plain white studio), then the character (subject capped at
700 chars), then only the rules a sheet needs, one short sentence each: leather-only armour, headwear,
elf ears (only for elves), child/teen proportions, clean skin and clean well-kept clothes.

What the validation runs found, each fixed and pinned by a test:
* **Passing states drawn as features** — "rote Stirn bei Wut, Tränen … vor Wut" became red marks (Darrag);
  "Zunge streicht über die Lippen" a tongue sticking out (Eolan). Anger, tears, trembling, twitching,
  blushing, sweating, licking are stripped like wounds.
* **Scars** — even a scar the sheet calls almost faded, with "fully healed, pale silvery line" added,
  rendered as a fresh red gash, and that sentence put slashes on hands and robe. Scars are left out of
  image prompts entirely; this model cannot draw a subtle one.
* **A dropped clause starting a sentence** left fragments ("und die rechte Augenbraue"): the whole sentence
  now goes. "faded blue wool coat" stays (a costume, not a scar).
* Hedges "unklar" / "wird erwähnt" drop speculative sentences.

**Portrait (identity image) got the same treatment.** Old prompt ~2 800-3 700 characters, new ~875, framing
first ("full-length studio photograph … head to shoes … head in the upper third … plain white studio"). Identity
renders cropped exactly as the profile picture is, scored by the portrait check, 4 seeds each:

| | old prompt | new prompt |
|---|---|---|
| Karyla | 0/4 (scenery backdrop every time) | 4/4 |
| Darrag | 4/4 | 4/4 |

Both prompts share one rules line, which now again carries the per-character costume cut and colours for armed
characters (`_character_design_variation`; the first short turnaround had dropped it) and names the setting
("in the world of The Dark Eye"). The portrait asks for empty hands; weapon handling stays in the story prompt.

**The sheet follows the finished portrait.** After the portrait passes its check, the vision model describes what
it shows (`look`: hair colour/length/style, facial hair, eye colour, `look_phrase`, punctuation stripped and short),
and the turnaround and story prompts are rebuilt with "exactly as in the portrait: …". Found on Darrag, whose sheet
says nothing about hair: the portrait had shoulder-length hair and the turnaround a crop; the face transfer copied
the face but not the hair, and the same-person check failed on all three sheet attempts. Best effort: no
description, no change.

Open: robes can still come out with ragged hems; the story-moment prompt is still long.