LTC2945CMS#PBF - Wide Range I2C Power Monitor

#!/usr/bin/env python3
"""Physical materials for a step2glb GLB of KiCad's MSOP-12 model (one mesh, materials told apart by the STEP's own
base colours; step2glb writes base colours only, so glTF defaults render everything as rough metal). Sets:
  dark epoxy   (base colour luminance < 0.1)        -> "Adom.Body (epoxy)"            metallic 0, roughness 0.55
  pin-1 dimple (0.1 to 0.5, warm grey)              -> "Adom.Body (pin-1 dimple)"     metallic 0, roughness 0.75
  leads        (0.5 to 0.75)                        -> "Adom.Leads (matte tin)"       metallic 1, roughness 0.35, tin colour
  mark         (the Adom.LaserEtch node's material) -> "Adom.LaserEtch (virtual MPN)" metallic 0, roughness 0.7
Colours are kept except the leads. usage: materials_bycolour.py in.glb [out.glb]"""
import sys
from pygltflib import GLTF2, PbrMetallicRoughness
TIN = [0.72, 0.72, 0.70, 1.0]
src = sys.argv[1]; out = sys.argv[2] if len(sys.argv) > 2 else src
g = GLTF2().load(src)
etch_mats = set()
for n in g.nodes:
    if n.mesh is not None and (n.name or "").startswith("Adom.LaserEtch"):
        etch_mats |= {p.material for p in g.meshes[n.mesh].primitives}
done = []
for i, m in enumerate(g.materials):
    pbr = m.pbrMetallicRoughness or PbrMetallicRoughness()
    c = pbr.baseColorFactor or [1, 1, 1, 1]; lum = sum(c[:3]) / 3
    if i in etch_mats: m.name, metal, rough, col = "Adom.LaserEtch (virtual MPN)", 0.0, 0.7, None
    elif lum < 0.1: m.name, metal, rough, col = "Adom.Body (epoxy)", 0.0, 0.55, None
    elif lum < 0.5: m.name, metal, rough, col = "Adom.Body (pin-1 dimple)", 0.0, 0.75, None
    elif lum < 0.75: m.name, metal, rough, col = "Adom.Leads (matte tin)", 1.0, 0.35, TIN
    else: sys.exit(f"ERROR: unexpected material {i} colour {c}")
    pbr.metallicFactor, pbr.roughnessFactor = metal, rough
    if col: pbr.baseColorFactor = col
    m.pbrMetallicRoughness = pbr; done.append(m.name)
if "Adom.Leads (matte tin)" not in done or "Adom.Body (epoxy)" not in done:
    sys.exit("ERROR: body or leads material not found")
g.save(out); print("OK", out, done)