Scenario Maya Retopology Uv

Maya retopology and UVs

Expert retopology is a loop plan with the fewest polygons that still deform: landmarks first, rings around eyes and mouth, three loops per joint, poles where nothing moves, a bend test that says whose fault a bad crease is. Expert UVs spend texels where the camera looks, at a density derived from the closest shot, with padding that survives mips. Without a mouse the agent reuses approved topology, builds from data, and measures then renders every stage. If a sibling skill named here is missing from your available skills, ask the user to install it (npx skills add scenario-labs/skills --skill <name>); unattended, proceed from tool schemas and flag the gap.

REQUIRED BACKGROUND: scenario-maya-expert (execution channel, review loop, 2027 version traps). Toolkit: scripts/mx_retopology_uv.py (import mx_retopology_uv as RU), built on mx_audit, mx_review and mx_run.

Status (2026-09-24): every Maya call is not yet run in Maya (not installed); 99 pure and 40 fake-Maya checks pass offline. First run tests/code/maya-retopology-uv/run_all.sh, then fix what job_probe_commands reports.

Stance (the expert delta)

• Landmarks first, big polygons, then fill like a puzzle. FlippedNormals: starting small is "a terrible way to work"; loose is recoverable, tight is not (9N4rG5qHWgk [00:01:05] [00:02:07]). The loop map is data before any vertex; a template fit is gated at base density before spans are added.
• Reuse approved topology. FlippedNormals carry one perfect hand, ear or base mesh to every model ([00:10:11]); Jessica Dru Johnson's standard base cut face skinning from three days to 30 minutes (ZiYEO49B768 [00:58:51]). Quad Draw substitute: RU.fit_template.
• No automatic topology on what deforms. On a face it "will look normal, but it's not" (FlippedNormals [00:23:15]); automatic is for parts that do not animate ([00:22:13]). Retopologize serves props, armor plates, static cloth; on a torso or loose coat it is a flagged start that must pass the deformation gate.
• Isolate and bound deformation. Concentric rings around eyes and mouth, one control plus two support loops per joint, a flat loop from lip corner to jaw corner against shearing (Jessica [01:15:51] [01:30:10]), equal lid loop counts (FlippedNormals [00:21:41]). Poles in still areas or skin folds ([00:12:45]); triangles only in cavities; never n-gons: ZBrush triangulates them and blend shapes break ([00:05:31]).
• Test the bend before handoff, blame the right artist. antCGi: loops running along a joint (wrist, ankle, hip crease) are the modeler's fix; volume lost at a correctly looped hinge is the rig's, for correctives; prove it by swapping topology under identical weights (x07USYlvu2o [00:10:27] [00:16:24]). Fit lids over the real eyeballs, with enough loops to curve over the cornea on a blink ([00:15:18]; RlNnp4qQIrU [00:08:24]). Shear (Jessica [01:13:06]) judges face hinges; on limbs a linear blend shears even perfect rings [added, measured].
• Retopologize traps (Maya 2027 Help). polyRetopo re-runs on edits and file open: delete history; Pause the node while changing several attributes. Preprocess Mesh (default on) smooths detail: noisy 100k+ triangle input only. Hard surface 1 / 1 / 0. Never half a mesh. Edge component tags steer flow.
• Texel density from the closest camera. Paulino: frame the reference piece at the closest shot, double its screen pixels, round to a power of two, Get/Set on every shell (iL2iXizf9xM [00:02:33]). Film: one density, UDIMs. Games: uniform, scale up the head, stack mirrored shells (MLC s_KLbTUdKms [00:10:57]).
• Padding is a mip problem; bake prep is geometry. 4 px between shells, 2 px to the border, doubled per mip step; Room space stays 2 px (Maya 2027 Help). Hard edges on UV seams, one triangulation for bake and export, the whole mirrored model baked with mirrored UVs one tile over (Polycount), a low that hugs the high (On Mars YDu9pYMkkSM [00:17:45]).

Establish first

Clothes fused to the body (AI meshes). Tight garments become body topology with loops on the garment lines; loose layers get their own tube or template projected onto the fused source [added]; plates may slide but the torso stays one piece (Jessica [00:44:17]); wrinkles that never animate go to Retopologize or the bake (FlippedNormals [00:22:13]).

Workflow

1. Intake, read only. mx_audit.audit(source); the source stays the bake source. RU.prep_source makes the working copy (weld, soften, report non-manifold); a broken source is rebuilt or used only as projection target (P2). Orient by the transform (cm, Y-up, +Z front, feet at 0). GATE: numbers written; clay sheet looked at.

2. Map. Landmarks, ring counts per opening, joint stations, flows (mouth corner under the cheek; neck along the sternocleidomastoid, clavicle to skull back, antCGi RlNnp4qQIrU [00:09:32] [00:37:43]), a method per part. GATE: the map is JSON before any geometry.

3. Build per part.

   Part	Method	Call
   Face, head, hands, body with a base	landmark fit	RU.fit_template
   Limbs, fingers, sleeves, skirts, tails	plane sections, 1 + 2 loops per joint	RU.limb_stations, RU.build_tube
   Props, armor plates, static cloth	Retopologize	RU.retopologize(mesh, faces, hard_surface=...)
   Torso or face without a base	primitive base from scenario-maya-modeling, then fit	Retopologize only as a flagged start for Quad Draw (gui-paths.md)

   Then cavities: mouth bag, nostrils, eye pouch (FlippedNormals [00:25:16] [00:27:22]). GATE: mx_audit.verdict clean per part.

4. Relax, center, mirror. RU.relax_project, RU.snap_center, RU.mirror_half (weld 0.001, antCGi QW8w15J00Ok [00:02:56]); combine symmetric parts (e74KphYwMww [00:24:32]). GATE: no center drift, symmetry 100%.

5. Gate the topology. RU.retopo_report plus wire and clay sheets in the source's views.

6. Deformation-ready gate, before UVs (antCGi unwraps after it). RU.deform_test(mesh, chain, bends, review_dir=...) per limb (elbow and knee at 90 and 130 degrees, wrist, ankle, hip; twist judged mid-limb, never at shoulder or wrist, x07USYlvu2o [00:08:40]), kind="hinge" for jaw open, RU.lid_check(head, eyeball). Proxy weights, no skinCluster: binds are scenario-maya-deformation's. GATE: no topology verdict, lids ok, pose sheets looked at; rig verdicts travel as notes; prove a fix with RU.compare_variants (P19, P20).

7. UVs. Seams as edge loops (RU.loop_keys, RU.cut_seams): neck base, head slits, inside the mouth, sleeve line, back of the arm, wrists, waist, inner legs, boot tops, soles (MLC [00:01:37] to [00:08:05]); cloth on its real seams (Paulino [00:05:16]). RU.unfold, RU.optimize; limb shells RU.orient_shell then RU.straighten_rows (MLC [00:04:49]); RU.mirror_uvs(mode="mirror"). GATE: planned shells, no folds, distortion in band.

8. Density and packing. RU.density_from_camera (film) or RU.density_for_budget (games); RU.set_texel_density (head bias in games); RU.layout(scale_mode="off") with RU.mip_padding; UDIMs, or RU.mirror_uvs(mode="stack", offset_u=1.0) for game bakes, never where AO or a logo differs; RU.lightmap_set. GATE: RU.uv_report ok; UV and RU.checker_review sheets looked at.

9. Bake prep. RU.harden_uv_borders, RU.bake_check, RU.make_cage or RU.project_to_surface, RU.bake_copy, RU.overlap_review(low, high, out) (P21). GATE: high inside the cage, hard edges only on seams, one triangulation, silhouettes match.

AI character end to end: procedure P18.