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mcdisplay family

All variants wrap mcrun --trace under the hood; INSTR plus any name=value instrument parameters are forwarded straight to it. The default is mcdisplay/mxdisplay → pyqtgraph.

mcdisplay / mxdisplay (default = pyqtgraph)

Option	Description
INSTR	instrument file (.instr or compiled binary)
name=value ...	simulation parameters, passed through to mcrun
--default	automatically use instrument default parameter values
--no-mpi	forward --no-mpi to mcrun (simulate without MPI)
-n, --ncount N	number of particles to trace (default: 300)
--dirname DIR	override output directory name
--inspect COMP	show only rays reaching component COMP
--invcanvas	invert canvas background
--tof, --TOF, --ToF	(McStas only) enable time-of-flight display mode

Interactive keys: q quit · p save png · s save svg (not on Windows) · space/F5 next ray · click a subplot to zoom, right-click to exit zoom · h/F1 component list.

mcdisplay-matplotlib / mxdisplay-matplotlib

Thin bash wrapper piping mcrun --trace output into a matplotlib 3D viewer — options are parsed by the wrapper script itself, not Python argparse.

Option	Description
INSTR	instrument file
name=value ...	simulation parameters
-n N, --ncount N, --ncount=N	number of particles to trace (capped at 1e2 by the wrapper)
--trace={1,2}	classic (1) or new (2, default) visualisation mode
--backend=NAME	matplotlib backend; pdf/pgf/ps/svg save a hardcopy instead of showing a window
--help	show wrapper usage and exit

mcdisplay-webgl / mxdisplay-webgl (NodeJS/vite-based)

Option	Description
INSTR	instrument file
name=value ...	simulation parameters
--default	automatically use instrument default parameter values
--no-mpi	forward --no-mpi to mcrun (simulate without MPI)
-n, --ncount N	number of particles to trace (default: 300)
-t, --trace N	visualisation mode (default: 2)
-d, --dirname DIR	override output directory name
--inspect COMP	show only rays reaching component COMP
--nobrowse	do not open a web browser
--timeout SEC	shutdown time of the local viewer web server (default: 300)

(The viewer ships prebuilt; only if its dist/ is missing does the first run perform a one-time npm install && npm run build, which needs internet access and can take minutes.)

mcdisplay-webgl-classic / mxdisplay-webgl-classic

Option	Description
INSTR	instrument file
name=value ...	simulation parameters
--default	automatically use instrument default parameter values
--no-mpi	forward --no-mpi to mcrun (simulate without MPI)
-n, --ncount N	number of particles to trace (default: 300)
-t, --trace N	visualisation mode (default: 2)
-d, --dirname DIR	override output directory name
--inspect COMP	show only rays reaching component COMP
--first COMP / --last COMP	zoom range start/end component
--invcanvas	invert canvas background
--nobrowse	do not open a web browser

mcdisplay-cad / mxdisplay-cad (bonus: export instrument geometry to CAD)

Requires the cadquery Python package.

Option	Description
INSTR	instrument file
name=value ...	simulation parameters
--default	automatically use instrument default parameter values
--no-mpi	forward --no-mpi to mcrun (simulate without MPI)
-n, --ncount N	number of particle rays to include (default: 0 — geometry only)
--dirname DIR	override output directory name
-t, --trace N	mcrun --trace level: 1 (default) legacy wireframe, 2 solid primitives
-s, --segments N	tessellation resolution (circle segments, default: 16)
--tubes	draw lines as solid cylinders (rays too, when -n > 0)
-f, --format FMT	output format: glb (default), gltf, step, stl, vrml, obj, ply, off, xml/x3d, vtk, vtkjs

mcdisplay-plopp / mxdisplay-plopp

Requires scipp and plopp (plus ipympl and jupyterlab for the interactive UI). Without -o, opens a 3D JupyterLab UI.

Option	Description
INSTR	instrument file (.instr or compiled binary)
name=value ...	simulation parameters
-n N	number of rays to trace (default: 100)
-o, --output FILE	write static png/pdf/svg 2D projections instead of opening the UI
-y, --yes	forwarded to mcrun: use defaults for unset parameters (always on in the UI)

mcdisplay-mantid / mxdisplay-mantid (export Mantid instrument definition)

Writes INSTR.xml, a Mantid IDF built from the instrument geometry and its Mantid-flagged detector monitors.

Option	Description
INSTR	instrument file
name=value ...	simulation parameters
--default	automatically use instrument default parameter values
--dirname DIR	override output directory name
-n, --ncount N / --mpi N	accepted, but always forced to 1

mcdisplay-matlab / mxdisplay-matlab (legacy Matlab/Octave/iFit variant)

A second, older implementation living under tools/matlab as a bash wrapper around a .m script rather than Python. Runs under Matlab or Octave — the wrapper auto-detects whichever is available, preferring Matlab, then Octave, and falls back to the plain Python mcdisplay if neither is found.

Option	Description
INSTR	instrument file (.instr or compiled binary)
name=value ...	simulation parameters, forwarded to mcrun
-m	explicitly request Matlab
-o	explicitly request Octave
-h	show wrapper usage and exit
-n N, --ncount N	number of particles to simulate
--inspect=COMP	only plot components matching COMP — a partial name (e.g. Monitor), or an interval (Monok:Sample, 2:10, 2:end)
-png, -jpg, -fig, -eps, -pdf, -tif	(parsed by mcdisplay.m itself, not the wrapper) export the 3D view to the given format

(-m/-o/-h are wrapper-level flags and must come first; the export-format flags and --inspect are forwarded as-is to the underlying .m script.)

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Last Modified: Tue Nov 3 18:52:15 2026