SciViz Star Projects

Flagship scientific visualization projects focused on deterministic, performant pipelines bridging OVITO/LAMMPS data to Blender for real-time inspection and production-grade rendering.

Why

Scientists need physically faithful previews and stable renders. We avoid re-simulation inside Blender: we ingest ground-truth positions from OVITO/LAMMPS, instance geometry via Geometry Nodes, and—when rendering—use point caches (PC2/Alembic) for deterministic playback.

Repository Layout

projects/ └─ ovito-blender-visualizer/ # OVITO/LAMMPS dump → Blender GN instancing + PC2/Alembic bake docs/ └─ media/ # demo GIFs and gallery stills

Features (engineering-grade)

• Real-time viewport playback from multi-frame dumps.
• Render-safe determinism via PC2/Alembic + Mesh Cache (Time Mode = FRAME).
• Geometry Nodes instancing: replace the atom prototype with any object (spheres, icosahedra, molecules).
• Shape/scale control per instance; optional filtering by LAMMPS type.
• Cycles-ready: supports motion blur (enable Deformation MB), metal backend stability notes for macOS.
• Production hygiene: pre-commit (black, flake8), protected main, CODEOWNERS, CI hooks.

Quickstart

1. Open Blender 3.6+.
2. Load projects/ovito-blender-visualizer/ script into the Text Editor.
3. Set your dump path (LAMMPS/OVITO). Run the script.
4. Replace Atom_Proto with your own prototype object if desired; adjust atom scale in GN.
5. Viewport: press Play. Render: bake to PC2/Alembic and attach Mesh Cache for deterministic frames.

Determinism & Point Cache (PC2)

• PC2 (Point Cache 2) is a per-frame binary cache of vertex positions. It removes Python/handlers from the render loop.
• Use Alembic as an alternative (interchange, stable on DCCs).
• Recommended render path:
  1. Generate carrier mesh (N vertices = N particles).
  2. Bake PC2/Alembic.
  3. Attach Mesh Cache (Time Mode = FRAME).
  4. Keep GN after Mesh Cache to instance the prototype at baked positions.

Performance Tips

• Large systems → prefer PC2/Alembic for render.
• Lower GN draw cost using simpler prototypes (e.g., low-poly spheres).
• If using GIFs in docs, keep ≤ 10–20 MB (decimate frames, 12 fps, 480–360 px, limited palette).

Contributing

• Branch from main, push feature branches, open PRs.
• Linting: pre-commit run --all-files.
• Protected main: at least 1 CODEOWNER review required.

License

MIT. See LICENSE.

Acknowledgments

Inspired by OVITO and Blender communities; tailored for scientific graphics pipelines.