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ViSAGE

Interactive 3D visualization for SAGE semi-analytic galaxy formation outputs.

ViSAGE renders dark matter haloes and SAGE galaxies together in a browser-based interactive viewer, powered by PyVista and Trame. It is designed to work directly with the output of SAGE26, and includes guided setup flows for two companion tools: SAGEswarm (PSO calibration) and LightSAGE (lightcone extraction, upstream repo sage-home/sage-lightcone).

Key features

Feature Description
Dual layers Haloes and galaxies rendered simultaneously as world-space gaussian splats
Timeline Scrub, play, pause, and step through every snapshot at 0.1×–5× speeds
Layer controls Toggle visibility, adjust opacity, choose colour-by mode, pick from 27 colormaps
Structure mode Layered galaxies: cold-gas envelope + outer CGM/Hot envelope, sized by SAGE fields
Navigation Fly to halo index, galaxy index, coordinates, or sub-box — focus mode masks everything outside
Tab-aware Focus One button that does the right thing on whatever tab you're in
Double-click any point Populates Target halo + galaxy IDs and (if Focus is active) carries the camera to the selection
Point picking Double-click anywhere in the viewport — works on every tab
Multi-model Switch between SAGE flavours of the same sim; overlay two compatible models simultaneously
Lightcone Mode Open a LightSAGE lightcone output in the same Explore UI; the snapshot slider becomes a redshift/time cut over the cone, plus an optional false-colour synthetic-photometry (SED) imaging layer
Launch Mode wizard Guided flows to clone/build/configure/run SAGE26, SAGEswarm, or LightSAGE, with a labelled parameter form for every config file
Story Mode Author JSON "stories" and play them back as full presentations over the live 3D view — text/media/equation overlays, camera motions, time sweeps
Embedded console Real shell terminal + Python REPL + natural-language SAGE commands in one tab, with multi-session tabs, script loading, and a pop-out window
Output Screenshots (PNG/JPG/TIFF), movies (GIF/MOV/PNG-sequence) at 1–60 fps, 1×/2×/4× supersampling
Camera bookmarks Save / restore / delete arbitrary viewpoints
Multi-CPU loading Snapshot prefetch pool keeps playback smooth
Remote use Trame web server — run on a cluster, view in any browser
Enter to run Every input submits on Enter, equivalent to clicking its action button

Quick example

pip install sage-viewer
visage --par input/millennium.par
# → Open http://localhost:8080

Supported simulations

  • miniMillennium — 62.5 Mpc/h box, 64 snapshots, lhalo_binary trees
  • microUchuu — 96 Mpc/h box, 50 snapshots, lhalo_binary trees

Documentation sections