Launch Mode¶

Launch Mode sets up and runs SAGE26 and its two companion tools, LightSAGE (lightcones) and SAGEswarm (calibration), without leaving the viewer: big buttons for each choice, a progress page for each run, and the model opening straight in ViSAGE when it's done.

Opening Launch Mode¶

cd /path/to/SAGE26      # or the folder you want SAGE26 to live in
visage

Open the printed URL. From inside a model, the Launch Mode menu (the SAGE-logo button, top-left of the toolbar) lists SAGE26, LightSAGE and SAGEswarm (each opens that tool's page) and Setup Wizard (the home page), then the models opened this session.

Home¶

Three picture cards, one per tool, each saying whether it's installed, and Load a previous model, which lists every SAGE26 model and lightcone ViSAGE can find (size, date, galaxies, .par). Click one to open it.

A tool's page¶

The tool's picture and status on the left; its actions on the right:

Button	What it does
Run	Opens the tool's setup page (below)
Load existing	SAGE26 models or LightSAGE lightcones as buttons; click one to open it
Install	Gets the tool ready (below)
Check for update	Compares the checkout with GitHub on the button itself; when it's behind, the button becomes Update
Clone / Re-clone	A fresh copy from GitHub, then Install. An existing checkout is moved aside (never deleted); a first clone goes beside your other tools

Install and Clone run on their button: it spins, shows the step it's on and the latest output line, then says how it went. If something fails, the button turns red; click it to see the full output.

What Install does:

SAGE26: on a first install, first_run.sh (makes the folders, downloads the mini-Millennium trees); then make on every core, falling back to a serial build when there's no MPI compiler. On Debian/Ubuntu/WSL the build is pointed at the system HDF5.
LightSAGE: the libraries its tools need (CMake, Boost and HDF5, through Homebrew on macOS or apt inside WSL), the photometry packages (fsps, astropy) and the FSPS stellar libraries they read (into ~/.visage/fsps when SPS_HOME isn't set; about 1 GB), then the two tools, sage2kdtree and cli_lightcone. SAGE itself is never built from LightSAGE: ViSAGE feeds it your SAGE26 output.
SAGEswarm: its Python packages (requirements.txt). It runs SAGE26, so it says if SAGE26 still needs installing.

Setting up a run¶

Run opens the tool's key choices as big buttons:

SAGE26: which simulation (one card per .par, with its box, snapshots and tree type), the physics switches (described by the .par's own comments), and Run on: 1 process, or 2, 4, 8 … up to your cores under MPI (mpirun -np N). MPI is offered when mpirun is installed and SAGE26 was built with it; otherwise the row says why.
LightSAGE: which SAGE26 model to build from (models without saved star-formation histories are greyed out: they can't have photometry), how much sky and how deep (presets, or Custom), the surveys to observe it with, and the light: photometry, dust, infrared glow, emission lines, disk & bulge.
SAGEswarm: the observations to match (each constraint, grouped), how hard to search (particles × iterations, with the number of SAGE26 runs that means), and the free parameters from its space file.

Name is the run's name, and it is its output: SAGE26's OutputDir (and a .par of that name when you run), LightSAGE's OUTDIR/OUTFILE, SAGEswarm's OUTPUT_PATH. If the name already belongs to a model or lightcone, a warning says running would replace it.

All settings shows every value in the file, grouped into sections, with a search box; on/off values are switches and each value shows its comment from the file. The setup page and All settings always agree: change something in either and the other shows it.

While it runs¶

The run page shows:

the stages, an overall progress bar and a few numbers, read from the tool's own output (SAGE26's percentage and time left, with a tree branch growing as the trees are built; LightSAGE's stages and photometry steps; SAGEswarm's rounds as a bar and its particles as circles that fill as each one runs, and the best score so far);
the tool's terminal, with what the run is making beside it: a SAGE26 box filling with galaxies, a lightcone filling outwards from the observer, or SAGEswarm's newest plot of each constraint;
Cancel, and when it finishes Open in Explore / Open in Lightcone view, or Change settings if it stopped.

The terminal is never narrower than 140 columns (SAGE26 redraws its banner and progress bar in place, up to 138 columns wide); in a narrow window its font shrinks, and long lines are cut off at the edge rather than wrapped.

Opening a model¶

Opening a model or lightcone, from any of these pages or from the Launch Mode menu, restarts ViSAGE on it: the page shows Opening … and reloads itself when it's ready.

Where ViSAGE looks for things¶

The folder you launch from anchors the session:

What	Where
SAGE26, LightSAGE, SAGEswarm checkouts	The launch folder, its parent, then your home folder
`.par` files	`<SAGE26>/input/` and `<launch folder>/input/`
Models	`<SAGE26>/output/`, `<launch folder>/output/`, `<launch folder>/sage_outputs/`
Lightcones	`<launch folder>/sage_outputs/` (each build in its own folder)
Screenshots, recordings, exports	`<launch folder>/sage_outputs/session_<timestamp>/`
Build and run scripts	`~/.visage/` (never inside a tool's checkout)

On Windows¶

The three tools build and run Unix programs, so on Windows every install and run happens inside WSL (Windows Subsystem for Linux), automatically:

If Linux build tools are missing, the home page says so and offers Install Linux build tools (apt inside WSL, as root, so no password).
Checkouts stay on your Windows drive; paths are translated both ways (C:\... ↔ /mnt/c/...).
If WSL isn't installed, the home page says how (wsl --install in an administrator PowerShell). Opening existing models and lightcones works without it.

See Installation › Windows.

Fixes ViSAGE makes to the LightSAGE tools¶

ViSAGE builds LightSAGE's two tools itself and carries a few fixes to them as patches (in visage/wizard/patches/lightsage/). Each build applies the patches, builds, and takes them out again, so your LightSAGE checkout stays exactly as upstream has it and only the built tools carry the fixes. A patch LightSAGE already includes is skipped.

Patch	Fixes
Rotate spins with the box tiling	When a lightcone tiles copies of the box, each copy's axes are permuted. Positions and velocities were permuted but galaxy spins weren't, so each galaxy's orientation to the observer (its inclination) was wrong. Spins now get the same permutation, with the sign flip an axial vector takes when two axes swap (a mirror).
Sort iterator for newer compilers	Newer C++ standard libraries (Xcode / Command Line Tools 27) sort through `it[n]`, which LightSAGE's sort iterator didn't support, so the tools no longer compiled.

Closing¶

The × at the top right closes Launch Mode and returns to the model you had open. Rescan looks for the tools again (after installing one outside ViSAGE, say).