Modeling

modeling

Purpose

Convert approved design into geometry that looks right from every angle AND deforms believably through a full animation range. Topology is the most underestimated determinant of animation quality.

Scope

D17 Organic [SIT], D18 Hard-surface [SIT], D19 Character [REQ], D20 Creature [SIT], D23 Retopology [SIT], D24 Topology [REQ], D135 Base meshes [OPT]. Sculpting craft and anatomy numbers live in sculpting-anatomy but this skill consumes them.

Activation Conditions

• User asks to model, box-model, boolean, retopo, fix topology, edge flow, poles, LODs, base meshes
• Orchestrator fires modeling/retopo stages
• Feedback loop from rigging: deformation failed
• Use modeling

Non-Activation Conditions

• Sculpt brush settings / dyntopo vs multires (→ sculpting-anatomy) unless handing off
• UV unwrap (→ lookdev)
• Design/silhouette still unlocked (→ character-design first)

Instructions

1. Refuse to model without a sheet (or at least a locked silhouette) and a scale master.
2. Choose workflow (decision 5.3).
3. Organic (D17): box/subdiv, curvature-driven, Subdivision Surface modifier. Quads.
4. Hard-surface (D18): blockout → Bevel (weight-based) → booleans → weighted normals → apply late. Sharp edges with bevel logic, not raw ngons.
5. Character (D19): import turnaround as background images; real scale. Start from primitive, base mesh (D135), or sculpt. Body-part topology regions from Ch 31 atlas.
6. Creature (D20): driven by spec sheet. Silhouette-to-mass primitives first.
7. Topology rules (D24):
   • Quads are the unit.
   • Edge loops follow deformation (joints, face loops).
   • Poles (E3/E5) placed in stable regions, not on a bending equator.
   • Density where it deforms and where the camera sees it.
   • Non-manifold = error.
8. Retopo (D23): shrinkwrap/snap to sculpt; deformation-friendly cage; decimate sculpt only for viewport, not as the cage.
9. Bend tests before lookdev: squat, reach, twist, look-back. If it breaks, fix topology here.
10. LOD plan for backgrounds (Ch 26 / D24).
11. Apply transforms. Freeze proportions.

Procedures

Character modeling → Body parts → Topology regions

Use Depth 31 joint-by-joint and facial topology atlases (vertex counts, pole/transition patterns, density budgets).

Hard-surface workflow → Modifier stack → Result

Mirror → Booleans → Bevel → Weighted Normal → (optional) Subdiv. Keep stack live as long as possible.

Retopo

Prep (decimate display) → wrap new quads → project → apply shrinkwrap → check loops at joints → bend test.

Decision Logic

• Film realistic hero → sculpt-first then retopo.
• Stylized boxy → box+subdiv, maybe skip sculpt.
• If deformation fails later: return here, do not "fix in weights."

Inputs

• Character sheet / creature spec / design lock
• Scale master, poly budget
• Optional high-poly sculpt from sculpting-anatomy

Outputs

• Deformation-ready mesh(es)
• Topology notes / LOD plan
• Bend-test results
• Shared state: asset model status; lock.model when approved

Tools

Blender Edit Mode, modifiers (Mirror, Subdiv, Boolean, Bevel, Shrinkwrap, Decimate), optional RetopoFlow/Quad Remesher (learn system first). Ch 31 atlas. S-09 hard-surface supplement.

Constraints

No merged props-into-character. No ngons on deforming surfaces. No unapplied scale. No modeling without scale master.

Edge Cases

• Mechanical creature: hard-surface body + organic membranes (split objects).
• Base mesh (D135/Rigify) is legal; still retarget topology to the sheet.
• Scans: retopo, do not animate the scan.

Failure Modes & Fixes

Dependencies

• Needs character-design and blender-foundations
• ⇄ sculpting-anatomy
• Drives lookdev and rigging
• Feedback from rigging / animation

Related Skills

sculpting-anatomy, lookdev, rigging, character-design, costume-groom

Delegation Rules

• Anatomy landmarks / brush sculpt → sculpting-anatomy
• UVs → lookdev
• Armor plates as hard-surface stay here; garment sim mesh → costume-groom

Examples

• Stylized hero: box torso/limbs, subdiv 2, face loops from atlas, 16–24 eye ring, bend test squat.
• Mech: boolean kit, bevel weights, no subdiv on sharp panels, separate moving parts.

Required Knowledge / Context

• knowledge/domains/ch03-modeling.md
• knowledge/depth/ch31-topology-depth.md
• knowledge/system/02d-depth-supplements.md (S-09)

References to Shared Resources

• workflows/character-pipeline.md
• decision-engine 5.3, 5.16