img2threejs — Image to procedural Three.js
Rebuild the object visible in a reference image as a code-only procedural Three.js model,
gated by a staged sculpting pipeline and an AI-vision self-correction loop. This is
reconstruction-by-code, not photogrammetry, mesh extraction, or downloaded art packs.
Agent-agnostic: works under Claude Code, Codex, or OpenCode. Wherever this doc says "agent
vision" or "agent browser tool", use whatever the host provides — native image reading, a
browser MCP (playwright/chrome-devtools), the project preview, or a user-supplied screenshot.
This file is the always-loaded router: it holds the order of operations and every hard rule as one
line. The full contract behind each rule lives in the grimoire/ or docs/ file that rule names —
read the named file at the moment you reach that stage, not before.
Canonical shared checkout
Keep one checkout of this repository and let every host enter it through a symlink, so Claude and
Codex execute the same code instead of drifting apart:
~/.claude/skills/img2threejs -> <your checkout>
~/.codex/skills/img2threejs -> <your checkout>
When To Use
The user attaches/points to an object image and wants a procedural Three.js model, a
reconstruction/animation/destruction plan, a sculpt spec, or code. Also for material studies,
action-ready props, game objects, botanical/mechanical parts, and stylized reconstructions.
Core Promise
Sculpt from a photo, in order — never one-shot a mesh:
- Run
python3 forge/next.py --state .img2threejs/state.json [<spec>] first, at every start,
resume, and before every correction iteration. It reports the ordered checklist, exact next
command, evidence status, and bounded correction-loop status; it never replaces the spec/pass
gates. Obey a hard stop; never continue from memory.
- Validate the image is a suitable 3D target (
grimoire/intake/validation_rubric.md).
- Assess object class + complexity, then write a
qualityContract before any code.
- Spec it: component hierarchy, materials, lighting, pivots, sockets, action anchors.
- Build pass-by-pass from blockout → structure → form → material → lighting → interaction → optimization.
- Verify each pass with a screenshot compared against the reference; fail a pass if an
identity-defining feature is wrong even when the global score looks fine.
State explicitly when output is approximate/stylized/low-poly. A single image cannot reveal
hidden sides or guarantee exact geometry — say so instead of faking confidence.
Mandatory Local State Gate
Conversation context is disposable; .img2threejs/state.json is the local checklist authority.
Initialize once per reconstruction, then gate every step through it:
python3 forge/state.py init --state .img2threejs/state.json --reference <img> --profile <generic|cs2|character|animated-character> --spec object-sculpt-spec.json
python3 forge/next.py --state .img2threejs/state.json [object-sculpt-spec.json]
python3 forge/state.py mark <step-id> --state .img2threejs/state.json --evidence <path>
next.py prints the current step, pass, incomplete mandatory steps, exact next command, and
loop/max. Exit code 3 or status=stopped is a hard stop: report the reason and request input.
Never bypass it by reconstructing progress from chat history.
- Every completed step needs evidence; mark a non-applicable step
skipped only with --reason —
silent omission is forbidden. Loop counts derive from reviewHistory actions
(refine-spec/refine-code), not agent memory. Defaults: 3 corrections per pass, 6 total.
- Profiles add mandatory gates without changing the core order:
cs2 requires classification,
manifest, and a machine-readable CS2 review before AI review; character requires the character
contracts and landmark evidence; animated-character adds all of character plus the nine Stage R
steps (grimoire/readiness/animation_contract.md). Pick it whenever the rig must MOVE — on
character the Stage R gates are absent and the build completes without ever running them, which
is how animation used to ship broken. Its order is load-bearing: repair the mesh, freeze it, bind
additively, then verify parity. Every profile records suitability, projection applicability, and
material-evidence applicability. The state file is a resumability index, not visual evidence:
renders, specs, review history, and deterministic gates remain the authoritative artifacts.
Required Inputs
- one image path / screenshot / URL / attached image (if missing or unreadable, ask)
- intended use: prop, game object, hero render, playable/destructible object, animation rig
(default: real-time browser prop with interactive performance)
- for a CS2 request, an authoritative classification record (family/subtype and evidence refs) or
an explicit request for the user/vision provider to supply one; heuristic detection alone is not
enough to select a geometry adapter
The Loop (scripts do enforcement; agent vision does judgment)
Run scripts from the skill root (forge/...). Pure Python 3.10+ stdlib, no pip installs.
Full flags: grimoire/scripts.md. Never let a script score visuals — that is the agent's job.
- Analyze the image first (agent vision, before any script): work the layered observation
protocol in
grimoire/intake/image_analysis.md — identify/classify, decompose macro→meso→micro,
map part relationships, name materials in PBR terms, list identity-defining features, and flag
what the single view hides. Observation before inference; controlled 3D vocabulary; 3D
object-space not 2D image-space. Then probe local images:
forge/stage1_intake/probe_image.py <image> (metadata only, not a visual check).
1a. Local Spec Search — after image analysis, before writing or refining a spec, pull local
domain evidence (anatomy/PBR/wear/geometry/runtime/physics) rather than inventing it:
python3 forge/stage2_spec/new_pre_spec_assessment.py "Name" --image <img> --out assessment.json
(auto-runs BM25, auto-picks cs2/core_3d collection, writes a localSpecSearch bundle that
new_sculpt_spec.py --assessment carries into the spec). Full query-expansion recipe
(bilingual terms, focused search_specs.py retrieval, cache rules):
grimoire/intake/local_spec_search.md. MUST read it before retrying an incomplete or
domain-specific query.
1b. CS2 intake manifest — for a CS2 request, create and validate cs2-intake.json before
pre-spec authoring (admission, heuristic signal, classification, family/route resolution).
MUST read grimoire/intake/cs2_intake_contract.md completely before creating the manifest or
running pre-spec assessment.
1c. Optional fidelity evidence adapters — only when they improve an observed weak point; the
stdlib core remains authoritative. Thin/complex masks → local SAM2; character face/pose →
MediaPipe; weak front/back cues → Depth Anything V2
(forge/stage1_intake/run_vision_adapter.py <segment|landmarks|depth> ...; every adapter emits
provenance; monocular depth is relative only). MCP-only scene mutations never count as
implementation — write the proven change back to the spec or TypeScript, rebuild, recapture.
Full adapter + MCP routing and authority boundaries:
docs/integrations/reference_fidelity_tooling.md.
- Pre-Spec Assessment Gate — classify + score complexity + write the quality contract:
forge/stage2_spec/new_pre_spec_assessment.py "Name" --image <img> --complexity <simple|moderate|complex|ultra-complex> --out assessment.json. Rules: grimoire/intake/quality_contract.md.
Set objectClass.primaryDomain (object | character | hybrid) and fill the seeded
detailInventory (its targetMinDetails scales with complexity). Supported CS2 knife skins
and Glock-18 assets: always pass --cs2, which defaults the complexity tier to ultra-complex
(targetMinDetails 16, floor 9) — the finish/wear/hardware is the item, so CS2 is held to the
top fidelity bar. Author procedural GEOMETRY but route the FINISH through the projection path in
step 2c — a procedural finish for a patterned skin (Doppler/Gamma/Marble/Fade) reads visibly
wrong against the reference. Finish routes + rulebook: grimoire/build/cs2_finishes.md;
optional exact-texture acquisition: grimoire/intake/cs2_texture_acquisition.md.
2b. Detail inventory (do not skip for detailed subjects) — scan zones and enumerate every
identity-defining small detail (gloss, bevel, fasteners, linework, contours, stains):
forge/stage1_intake/build_detail_inventory.py <image> --mode grid-3x3 --out-dir <dir> --out di.json.
Each detail MUST map to a component.localFeatures or material.localOverrides entry — never
prose only. Taxonomy + 3D-term recipes: grimoire/intake/detail_inventory.md.
2c. Projection-first fidelity (characters AND reference-matched surfaces — supported CS2 skins,
decals, painted patterns) — when the goal is matching a specific reference's surface, put the
photo's own pixels on the mesh instead of approximating them procedurally. This is the single
biggest fidelity lever; a procedural material for a patterned surface is the #1 reconstruction
failure. Recipe (grimoire/character/likeness_maximization.md — its two levers generalize past
characters): solve the camera (stage1_intake/solve_camera_pose.py → referenceCamera),
de-light the reference (stage1_intake/delight_albedo.py, hard requirement — de-lighting is
what makes projection safe), then project the de-lit crop and bake it into UVs
(stage3_build/bake_projected_texture.py --mesh-id <id>). For a CS2 skin the projected de-lit
crop IS the finish — no procedural Doppler material. For characters, first capture landmarks
(stage1_intake/extract_landmarks.py --out anatomy.json), fill preSpecAssessment.anatomy,
route grimoire/character/reconstruction.md. A single view cannot show hidden sides — report
per-region confidence and request more views when it matters.
Character sub-routes, in order — decide what parts exist before shaping any, and shape the head
before the hair that sits on it:
- Parts —
grimoire/character/structure_decomposition.md
- Head —
grimoire/character/head_construction.md (what the likeness gate reads against)
- Hair —
grimoire/character/stylized_hair_threejs.md + parameter contract in
grimoire/character/threejs_hair_parameter_contract.json. Lock topology only after the
silhouette review passes: material tuning cannot repair wrong lock topology.
2d. Reference-free humanoid — a generic figure with no reference image has nothing to measure,
so fill anatomy from public canon:
forge/stage2_spec/humanoid_proportions.py <spec> --style-heads 8 --in-place. It writes
anatomy.source: "canon-table" so canon is never mistaken for measurement, refuses to run when
the spec names a reference image, and names anything the corpus does not supply rather than
interpolating it.
- Author the spec from the assessment:
forge/stage2_spec/new_sculpt_spec.py "Name" --image <img> --assessment assessment.json --manifest cs2-intake.json --out object-sculpt-spec.json.
Replace generic starter featureReviewTargets with the object's real identity-defining
systems (≤5 critical, ≤3 important per pass); for characters add anatomy-proportion,
face-landmark-placement, pose-silhouette, outfit-and-palette. Use 3D-graphics terms only
(grimoire/glossary/3d_vocabulary.md), never "nice/smooth/shiny". Classify every component's
topologyClass/topologyRationale per grimoire/intake/surface_topology.md before picking a
primitive — this is what prevents a continuous organic form from being picked as a box.
- When material fidelity matters and a source image exists, analyze each material's finish then
extract reference PBR evidence, both per crop (verify the crop is on the part you think it is):
forge/stage1_intake/analyze_texture.py <crop> --spec spec.json --material-id <id> --in-place
classifies the finish, extracts the gradient palette, and writes doc-grounded
MeshPhysicalMaterial scalars onto the material. Recipes + Three.js texture/PBR rules:
grimoire/build/threejs_texture_reference.md. Rule of thumb: solid albedo for flat paint,
real reference crop for patterned finishes.
forge/stage1_intake/extract_pbr_evidence.py <crop> --out-dir <dir> --material-id <id> --target-threshold 0.7.
Confidence < 0.7 is a stop/refine-input signal, not a pass. It is inference, not inverse rendering.
- For multiple named regions:
forge/stage1_intake/material_region_analysis.py --manifest regions.json --out-dir material-evidence --out material-analysis.json,
resolve each assignment from docs/materials/material-reference.json, wire it in with
forge/stage2_spec/apply_material_analysis.py.
- Emit the controlled material camera/crop contract (
forge/stage4_review/material_views.py),
compare visible-footprint crops (material_comparator.py), apply only bounded material-scoped
corrections (material_feedback.py), and record the blocking result (material_gate.py).
- Validate, then strict-validate before generating code:
forge/stage2_spec/validate_sculpt_spec.py object-sculpt-spec.json then --strict-quality.
Strict blocks shallow specs (a complex object with one root, no repetition systems, no
local overrides, no micro groups is NOT implementation-ready even if JSON validates).
- Locked build passes — only touch the currently unlocked pass:
forge/stage3_build/orchestrate_passes.py status object-sculpt-spec.json
forge/stage3_build/generate_threejs_factory.py object-sculpt-spec.json --out src/createObjectModel.ts
The generator is fail-closed: strict-quality must pass before it writes any factory, and a
future --pass-id fails until prior passes are reviewed continue. If blocked, preserve the
BLOCKED artifact and refine the subject-specific spec; do not substitute a generic template.
The local state adds --force only for a new pass or refine-spec; refine-code edits the
current artifact without regenerating it. Before overwriting, carry valid hand refinement back
into the spec; generated code must not be the only copy of reconstruction decisions.
6a. Hitting a triangle budget. performanceBudget.targetTriangles selects a tessellation tier
for every primitive with segment counts (low ≤6k, standard ≤60k, else hero) and caps
implicit-surface sampling grids. Where a tier is not precise enough, add
geometryDescriptor.decimate: {"targetRatio": 0.4} to that component — a quadric collapse in
the generated factory, run before skin binding so weights are computed on surviving
vertices. It keeps position only (normals recomputed), so it is refused on an
authored/unwrapped uvStrategy. Offline LOD tiers:
forge/stage3_build/decimate.py <mesh.json> --ratio <r> --json.
- Render the current pass in a browser/preview, capture a screenshot at a review viewpoint.
7a. Off-axis and placement gates — a single review viewpoint is not evidence about the model.
Capture a turntable, not one frame, and run all three; each catches a defect class the older
gates pass by construction (a hole through a skull, a hat at hip height and a floating charm all
survived eight front-only review rounds):
forge/stage4_review/turntable_gate.py --capture 0=front.png --capture 90=right.png --capture 180=rear.png --capture 270=left.png --json
node runtime/scripts/export_mesh_geometry.mjs --url <preview> --out meshes.json then
forge/stage4_review/self_intersection.py meshes.json --json
forge/stage4_review/attachment_anchor.py object-sculpt-spec.json --measured measured.json --json
All three exit 0 clean / 1 gate failure / 2 error. A failure blocks continue even when
the global fidelity score passes. Read sampledVertexCount / unmeasuredAttachments /
missingAzimuths before believing a clean verdict: each names what the gate did not look at.
- Run deterministic gates before AI vision. MUST read
grimoire/review/gates_reference.md and grimoire/review/self_correction.md completely. Run
forge/stage4_review/diagnose_render.py and record the passing Tier 1 result with
--spec object-sculpt-spec.json --pass-id <pass> --in-place; for non-planar forms also run
forge/stage4_review/diagnose_render_multi_angle.py with the fixed view and at least two
meaningful orbit views. Then run
forge/stage3_build/orchestrate_passes.py check object-sculpt-spec.json --pass-id <pass>.
- Package one side-by-side sheet, then inspect it with agent vision:
forge/stage4_review/make_comparison_sheet.py --reference <img> --render <shot> --out cmp.png --json.
- Record the review (overall + per-layer + per-feature scores + decision):
forge/stage4_review/append_review.py object-sculpt-spec.json --pass-id <pass> --fidelity <0-1> --action <continue|refine-spec|refine-code|request-input|stop> --summary "..." --render-screenshot <shot> --comparison-image cmp.png --ai-vision-score <0-1> --layer-scores-json '{...}' --feature-reviews-json <f.json> --in-place.
For the CS2 family path, produce the versioned report first with
forge/stage4_review/cs2_review.py --manifest cs2-intake.json --metrics cs2-review-inputs.json --scene forge/tests/fixtures/knife_review_scene.json --out cs2-review.json
and attach it with --cs2-review-json cs2-review.json --review-scene-json forge/tests/fixtures/knife_review_scene.json.
A failed family, painted-region, projection-coverage, critical-detail, or orbit gate blocks
continue even when the global score passes. See docs/cs2/review-gates.md.
- Sync pipeline state after manual review edits, record checklist evidence, then re-run the local
state gate before another correction or pass:
forge/stage3_build/orchestrate_passes.py sync object-sculpt-spec.json --in-place
python3 forge/next.py --state .img2threejs/state.json object-sculpt-spec.json.
- Before declaring completion, run
forge/stage4_review/check_part_coverage.py --spec object-sculpt-spec.json --manifest parts.json
and verify the action-ready hierarchy. Mark part-coverage and action-ready only with evidence.
GLB-mediated v2 render-fidelity track (1.5 alpha)
When the user supplies a GLB as an intermediate reference, the browser-rendered GLB is the
structural and visual baseline for an independently authored procedural factory. The raw GLB is
never pixel evidence and its topology/materials are never copied into the factory. Before any
factory edit — full contract in grimoire/build/python_threejs_render_bridge.md, machine-readable
schema in docs/specs/render-profile.v2.schema.json (+ example; fail-closed validation):
forge/stage1_intake/probe_glb.py first. A merged one-node/one-mesh asset is insufficient
for semantic labels; request a multipart GLB or a browser semantic-ID pass before claiming
exact regions.
- Author ONE shared
render-profile.v2 (forge/stage4_review/validate_render_profile.py) used by
both the GLB and procedural routes. Region IDs are subject-specific, never inherited from the
example profile; declare the required set in extensions.requiredSemanticRegions so omission is
a hard validation error.
- Capture six passes per admitted view (
beauty, alpha-silhouette, semantic-id, depth,
normal, roughness-material-id); score with forge/stage4_review/compare_region_passes.py.
Missing semantic-ID data blocks per-region confidence rather than falling back to whole-image
scores.
- Use region-specific continuous geometry — never replace a face/head volume, cloth shell, or tail
with floating primitives when the region's silhouette requires a continuous surface.
- Run ONE correction group per loop, in order:
camera → silhouette → face → clothing → accessory → materials → lighting; recapture the full pass set after each group and record the changed
group, hashes and score. Never combine groups when diagnosing improvement.
Gates (do not skip)
Before any visual review or continue decision, MUST read the full gate-by-gate contract in
grimoire/review/gates_reference.md (Divine Eye, VLM rescue, multi-angle, interior difference,
chirality, hair, CS2 review, bounded correction, Divine Eye fitting, screenshot feedback, assembly,
attachment, material, detail inventory, rig payload, character track). In short:
- Validate references first (
grimoire/intake/validation_rubric.md, check_reference_admission.py).
divine_eye.py is deterministic-first; the VLM (vlm_gate.py) is a gated last layer, never
consulted on a hard-gate failure.
- A non-planar form must hold from ≥2 angles (
diagnose_render_multi_angle.py).
- Measure INSIDE the silhouette every visual pass (
interior_difference.py). Silhouette IoU reads
~11% of figure cells: a model with its face deleted scored the same 0.8803 as the finished face.
- Every
-l/-r pair is a MIRROR, not a rotation — hard at spec time (validate_chirality). A pair
wrong the same way on both sides still passes, and needs medial_lateral_bias vs a reference.
- Hair subjects:
scalp_exposure.py is HARD and runs on geometry before any render; hair_gate.py
is soft and subordinate to it. A coverage shortfall never authorises widening the masses.
- Flat colour regions with hard boundaries (blaze/bib/socks, livery stripe, painted marking) are an
identity feature, so their boundaries are gated on geometry:
vertex_region_gate.py. Never a
texture — this pipeline emits code; the shape predicates live in _shared/vertex_paint.py.
- A curve claim ("curled into a hook, not a straight cone") needs
swept_arc_gate.py: silhouette IoU
passes a straight cone occupying roughly the right cells.
- Character builds validate the rig payload (
stage5_rig/validate_rig_payload.py) before binding a
THREE.Skeleton; it proves payload integrity only, never pose stress or likeness.
- A rig that must MOVE runs the animation gates too (
grimoire/readiness/animation_contract.md,
stage5_rig/rig_gates.py). A clip that exists is not a clip that plays: only G1
(maxSampledBindingDelta <= 2^-23) separates the two, and a gate whose input is missing reports
unevaluated, never a pass. Bind at IDENTITY in attached mode and take the display offset from
the mesh bounds alone; loop is decided by poseReturn, never by travel.
- CS2 builds also run
cs2_review.py against the versioned scene fixture.
- Local state enforces 3 corrections per pass and 6 total by default; reaching either limit is a
hard stop.
correction_loop.py may stop earlier on repeated defects, oscillation, or plateau.
continue requires a render + comparison sheet + AI-vision score ≥ threshold, every critical
feature ≥ its own threshold (grimoire/feedback/render_capture.md).
- Every model ships explodable AND clickable — a structure gate, not pixels
(
check_part_coverage.py, grimoire/build/geometry_patterns.md).
- Action-ready, attachment, material/lighting, detail inventory, and character-track requirements:
grimoire/readiness/action_rigging.md, grimoire/readiness/joint_attachment.md,
grimoire/feedback/shading_realism.md, grimoire/intake/quality_contract.md,
grimoire/intake/validation_rubric.md.
Self-Correction
After every pass, decide exactly one: continue | refine-spec | refine-code | request-input | stop.
refine-spec fixes a wrong/missing/shallow spec (re-validate, don't patch code around it);
refine-code fixes geometry/material/lighting that doesn't match a sound spec. Before making the
decision, MUST read the root-cause guide + fidelity scale in grimoire/review/self_correction.md,
record the decision, and re-run the local state gate.
Small features need a different instrument. Divine Eye's SSIM/tonal/edge signals run on a 64×64
luma grid, so a detail a few pixels wide is absent before any comparison happens. When fidelity
depends on individual tears, spars, fangs or eyes, use the four-tier microscope:
grimoire/review/divine_eye_microscope.md. Two empirically established rules from it: measure
fidelity on a component's visible footprint (full frame minus a component-hidden frame), never
on an isolation render; and never colour-gate a concave feature, where a dark ratio captures
cavity shading rather than material.
Transparency and Process Debugging
Report what changed each pass with evidence (exact values/coordinates), name what still doesn't
match, and never claim "done" when only "improved". A passing gate is not proof of 3D realism.
Full rule + examples: grimoire/review/self_correction.md.
Left and right
A left/right pair is a reflection, never a rotation: negate the lateral axis and nothing else,
(x, y, z) → (-x, y, z). With forward: +Z, Y up and a right-handed frame, the character's own
left is +X. The convention lives as code in forge/_shared/chirality.py
(CHARACTER_LEFT_SIGN), with two different gates for the two defects that shipped from getting it
wrong: validate_chirality catches a rotation-mistaken-for-reflection at spec time, and
medial_lateral_bias vs a reference catches a pair that is wrong the same way on both sides.
Reflecting also inverts triangle winding — flip it back on the mirrored side or flatShading
lights the limb as though lit from behind. Full write-up with the measured defects:
grimoire/scripts.md ("Left and right").
Hair
Hair has its own subsystem because it has failure modes no other gate can see. Full contract,
measurements and non-goals: docs/HAIR_PIPELINE.md. The hard rules:
- Roots bind to the scalp as
(u, v), never absolute positions (hard validation error).
standProud is enforced by the generator, not advisory.
scalp_exposure.py is a HARD gate on geometry before any render; a coverage shortfall never on
its own authorises widening the masses.
- Default representation tier is
shell, not locks; strand impression comes from faceting and
material (hair.human.code-only), since this skill emits no textures.
plane-card is rejected for hair (needs an alpha texture this skill cannot emit).
- Hair is rigidly parented, never smooth-skinned (the geodesic field runs through the skull).
CS2 image-matched rule
For a CS2 item, the target is observable agreement between the supplied image and the rendered
item: silhouette, proportions, edge profile, hardware layout, coating colour, pattern placement,
wear, roughness response, and camera framing. Every decision must be traceable to evidence or be
labelled as an approximation.
The initial CS2 family boundary covers supported knife subtypes and the Glock-18 pistol
adapter. Rifle, SMG, sniper, heavy, glove, unsupported pistol, and unknown knife subtypes must stop
with unsupported-family or unsupported-subtype; they must not receive another family's component
tree as a generic fallback.
The full layer contract (what each layer owns, must emit, and must never decide alone), the CS2
intake order, and the surface/review rule live in grimoire/intake/cs2_intake_contract.md — step
1b already requires reading it completely before intake state can advance. The canonical hand-off
is cs2-intake.json (schemaVersion: 1, states proceed | request-input | fallback | rejected | unsupported-family | unsupported-subtype); write it atomically, preserve unknown provider fields
under extensions, and never let a fallback erase prior evidence.
Forge Runtime Contracts
Subdivision runtime tests compile generated TypeScript against the showcase checkout. Set
IMG2THREEJS_SHOWCASE_ROOT to that checkout; without it, local runtime-only tests skip with an
actionable message while static contracts still run. CI should set IMG2THREEJS_REQUIRE_SHOWCASE=1
to turn a missing showcase checkout into a test failure.
IMG2THREEJS_SHOWCASE_ROOT=/path/to/img2threejs-showcase python3 forge/tests/test_subdivision.py
IMG2THREEJS_SHOWCASE_ROOT=/path/to/img2threejs-showcase python3 -m unittest discover -s forge/tests
IMG2THREEJS_SHOWCASE_ROOT=/path/to/img2threejs-showcase python3 forge/tests/test_showcase_tsc_smoke.py
Implementation Rules (brief)
TypeScript + plain Three.js unless the project uses a wrapper. Group factory
createObjectNameModel(spec, options), reconstruction data kept separate from renderer objects,
deterministic seeds for all procedural noise. Prefer primitives / Shape extrude / curve+tube /
instancing / displacement / generated canvas textures before any external art. Full geometry &
material recipes + hard-won failure patterns: grimoire/build/geometry_patterns.md.
Optional Python ↔ Three.js render bridge
When Python is requested for character rendering, use it as a deterministic job/evidence layer
around the browser Three.js runtime: camera-batch manifests, source/output hashes, readiness and
settle checks, screenshot persistence, masks, diagnostics, and comparison packaging. The target
Three.js browser route remains the rendering authority. Do not silently replace the procedural
TypeScript factory with Blender/VRM/GLB output. Full routing, manifest fields, and failure rules:
grimoire/build/python_threejs_render_bridge.md.
Standard character pipeline (merged 1.5 beta + alpha)
Use grimoire/readiness/standard_character_pipeline.md for character work. Beta owns the
strict sculpt/build/review gates; alpha owns deterministic camera manifests, browser screenshot
evidence and UniRig-shaped rig validation. CharacterGen, Tripo, VRM and other neural/asset
systems are opt-in adapters with source, checkpoint, license, coordinate conversion and output
hashes. They never silently replace the procedural TypeScript factory. Image-to-mesh systems emit a
static mesh with no skeleton, so their output is never animation-ready however good it looks.
Executable entry points: forge/stage4_review/render_bridge.py and
scripts/capture_threejs_playwright.py (init → browser capture → validate → diagnose; capture
must operate on the real showcase/browser route and leave readable PNGs in the workspace).
Output
- Analysis-only: suitability verdict + scores, object extraction, macro→micro hierarchy,
geometry strategy, material/lighting recipe, animation/destruction feasibility, plan + risks.
- Implementation: the above briefly, then edit code; verify with typecheck/build + a screenshot.
- Not feasible: name the blocker, ask for more views / cleaner image / accepted stylization /
a narrower target. "This cannot reach the requested fidelity from this image" is a valid result.