fascat

Show help

fascat --help
fascat help convert

Check version

fascat version

Inspect STEP input

fascat inspect motor.step
fascat --json inspect motor.step
cat motor.step | fascat inspect -

Convert to OpenUSD or glTF

fascat convert motor.step
fascat convert motor.step motor.usdc --profile realtime-desktop
fascat convert motor.step motor.glb --profile virtual-reality
fascat convert motor.step motor.glb --profile realtime-mobile
fascat convert motor.step motor.glb --profile mixed-reality
fascat convert motor.step motor.usda --debug --report report.json
fascat convert motor.step - --dry-run

Scope by assembly filter

fascat inspect motor.step \
  --filter 'path=*/Fasteners/*' \
  --filter 'name=Bolt*' \
  --metadata full \
  --pmi summary \
  --json

fascat convert motor.step motor.glb \
  --filter 'path=*/Fasteners/*' \
  --merge \
  --merge-mode by-material \
  --explode connected-components \
  --replace bounding-box \
  --batch-by-material \
  --merge-compatible-meshes \
  --split-large-meshes \
  --bake-materials \
  --bake base-color,opacity \
  --decimate \
  --remove-holes \
  --max-hole-diameter 3.0 \
  --remove-occluded \
  --run-lod-generators \
  --lod-preset vr \
  --target-triangles 80000 \
  --report report.json

For branch-specific conversion settings, put named filters and ordered steps in a pipeline file: 

[import]
metadata = "full"
pmi = true

[export]
metadata = "summary"
pmi = "metadata"

[[filters]]
name = "fasteners"
path = "*/Fasteners/*"
names = ["Bolt*"]

[[steps]]
op = "merge"
where = "fasteners"
mode = "by_material"
fascat convert motor.step motor.glb --pipeline realtime.toml

Tune tessellation and LODs

fascat convert input.step output.usdc \
  --heal-brep \
  --heal-tolerance 0.05 \
  --sag 0.1 \
  --angle 15 \
  --min-edge-length 0.02 \
  --max-edge-length 25 \
  --curvature-adaptive \
  --quality-report tessellation-quality.json \
  --target-triangles 500000 \
  --preserve-hard-edges \
  --preserve-material-boundaries \
  --preserve-small-parts \
  --normals hard-edges \
  --tangents \
  --validate-normals \
  --materials cad \
  --material-mode pbr \
  --merge-equivalent-materials \
  --uv1 lightmap \
  --texel-density 256 \
  --uv-padding 4 \
  --atlas \
  --atlas-size 4096 \
  --lods 0.5,0.25,0.1 \
  --lod-mode variants \
  --lod-screen-coverage 0.5,0.2,0.05 \
  --lod-per-part-budget \
  --lod-drop-tiny-parts \
  --lod-tiny-part-screen-size 2 \
  --validate-lods

Use .usda or .usd with --debug when you want inspectable text output. Binary .usdc, .gltf, and .glb output is rejected in debug mode.

Runtime export handoff

fascat convert input.step output.glb \
  --export-preset web \
  --quantize \
  --meshopt \
  --size-ladder \
  --file-size-budget-mb 50

fascat convert input.step output.obj --obj-materials --write-mtl --force
fascat convert input.step output.stl --stl-binary --force
fascat convert input.step output.fbx --fbx-materials --fbx-uvs --force

Validate output

fascat validate output.usdc
fascat validate output.glb
fascat validate output.fbx
fascat validate output.glb --geometry-quality --report quality-report.json
fascat validate output.glb --visual-preview preview.png --lod-preview-dir preview-lods/

JSON output

Every command supports --json for scripting: 

fascat --json <subcommand> | jq '.'
fascat <subcommand> --json | jq '.'

Dry run

Preview changes before applying them: 

fascat --dry-run <subcommand>
fascat <subcommand> --dry-run

Shell completions

# bash
fascat --install-completion bash

# zsh
fascat --install-completion zsh

# fish
fascat --install-completion fish