Look sheets

A look sheet is one generated image that merges a subject's reference photos into a multi-angle design sheet. A neutral canvas image pins the size so it never inherits a reference's dimensions, and every image (canvas + references) is resized to the same encoder target — that uniform sizing is what keeps the references driving the ART STYLE; when the references were left at their upload size the big canvas dominated the conditioning and the model fell back to a generic look. Output is ~1056×1568 (2:3) on the default engine. The panels tile the sheet edge to edge (thin separators only): a large front face panel, three head panels (three-quarter, profile, back) and three full-body views (front, side, back). Up to 9 references are blended (the studio caps uploads at the same number, so a 10th photo is refused rather than charged); each must be at least 512px and at most 1024px on the long side (the studio enforces both on upload; API references outside the range are skipped and reported in warnings). Identity tightens with the count — 1 is thin, 3 is enough, 4 is recommended, 9 is the maximum — and more references add render time, not sheet size (the output stays at the layout's resolution). A thumbnail is refused because upscaled it carries no facial detail and the model tends to paste it through as a panel. It is the canonical (and only) reference the studio feeds when you cast that subject. The pool is the subject's reference photos only — a character's avatar is card art and never joins it (an element's hero photo does: the form declares it a visual reference, and it leads the pool). Every panel holds the same neutral look: the persona's behavioral quirks never leak into the faces.

Like image generation, POST /v1/sheets is asynchronous: it charges, enqueues the render and answers 202 with one image job. Poll GET /v1/images/generations/{id} until succeeded (the sheet is in data[0], and its library_id is what you apply). Nothing becomes a subject's active sheet until you POST /v1/sheets/apply it — every accepted take keeps its history in your creation library.

The render gate. Once a character or element has an accepted sheet, char:<id> / el:<id> references in image and video renders feed that sheet. A subject WITHOUT a sheet cannot appear in a render yet — image and video generations answer 422 sheet_required before charging. Roleplay/chat is exempt: the persona sheet is enough to talk.

One sheet per subject, and one layout per subject kind — there is no layout to choose: turnaround for characters, hero for objects, scene for locations (the old identity/portrait split is gone; a trained Imprint will replace the sheet later). With zero stored references the sheet is invented from the persona/description alone — pass an explicit description to anchor it, or it falls back to the card text. Pass style to TRANSFORM the look instead of holding it (3D references into a photoreal sheet); omit it (or match) to stay as close to the references as the engine can hold.