java-draco-decoder

Tiny CLI to decode Draco-compressed GLB/GLTF into plain GLB 2.0 via LWJGL Assimp. Perfect pre-step before CPU voxelization.

Requirements

• JDK 17+, Maven 3.8+
• LWJGL 3.3.2+ with Assimp (Draco bundled)

Build

mvn -q -DskipTests clean package
# → target/draco-decoder-cli-1.0.0-all.jar

Usage

java -jar target/draco-decoder-cli-1.0.0-all.jar \
  -f in.glb [-f in2.glb ...] \
  [-filelist list.txt] [-o out] [-j jobs] [-v] [-h]

Options

• -f <path> add input (repeatable)
• -filelist <txt> one path per line
• -o <dir> output dir (default ./out)
• -j <n> parallel jobs (default: #CPU)
• -v verbose
• -h help

Examples

# single
java -jar ... -f tile.glb -o out
# batch
java -jar ... -f a.glb -f b.glb -o out -j 8
# list
java -jar ... -filelist assets.txt -o out

Output Each in.glb → out/in-decoded.glb (no Draco).

Notes

• Uses Assimp with safe defaults (Triangulate, JoinIdenticalVertices, etc.) and exports glb2.
• If you voxelize after: you can diff geometry vs CUDA output by sorting .xyzi arrays with jq and diff.

Troubleshooting

• Missing natives / UnsatisfiedLinkError: ensure LWJGL Assimp natives for your OS are available.
• “Draco library not present” under -v is informational; if import works, you’re good.

Embed (one-liner)

AssimpDracoDecode.decodeToUncompressedGlb(new File("in.glb"), new File("out/in-decoded.glb"), true);