The browser app¶
The display opens on a showcase event and needs nothing installed.
Two modes¶
| showcase | live | |
|---|---|---|
| source | the published figure JSON | a .root file you drop on the page |
| Python | none — instant | uproot under Pyodide, in your browser |
| entry stepping | disabled | enabled |
| rebinding collections | disabled | enabled |
Dropping a file switches to live mode. The file never leaves your machine: it is read with uproot compiled to WebAssembly.
First load
Live mode downloads Python, numpy, uproot, awkward and plotly once — roughly 30 MB, cached afterwards. The showcase does not need any of it, so the page is useful immediately and still works if Pyodide cannot start.
The collection panel¶
Beside the figure is every collection in the event: per-event object count, EDM4hep type, domain, provenance (transcribed from a DST bank, derived by SKELANA, or produced by the converter) and the relations in and out.
- Select a collection — everything in the figure that did not come from it dims to 12 %.
- Click a track, hit or vertex — its collection is selected and described.
- The dropdowns at the top rebind a role to another collection and re-render (live mode).
The wiring is meta.collection on every trace, set by figure.build.
Views and saving¶
panels / 3D switches between the four-panel figure and the detector scene; both are held in
memory, so switching costs no recompute. PNG, SVG and JSON save whichever view is showing,
named from the run and event (delphi_run48758_evt2666_3d.svg). The JSON captures your current
state — a rotated camera, a zoom — and can be reopened in the editor.
Captions¶
--title and --note describe one event. They are stored in figure metadata, never drawn
into the plot and never used as a heading, so a file you open yourself shows no caption rather
than inheriting someone else's physics. Everything true of any event — run, event, source,
charged/neutral, b-tag, B field — is rendered live from the same metadata.