TerraScope.jl

TerraScope.jl is a Makie-based local viewer for MT, density, shapefile, and seismic datasets. It keeps model/data IO, voxel handling, overlays, seismic curtains, and 3D viewing tools in one Julia package.

Quick Start

julia --project=. examples/launch_TerraScope3D.jl

examples/launch_TerraScope3D.jl is the only file you edit. Section 1 names the files by method, section 2 lists the shapefiles, and section 3 holds the startup settings; anything left out of section 3 keeps its default from examples/TerraScope3D.jl. Paths are absolute. The launcher checks each one before the slow work starts and prints what it found.

Inputs

Every input is optional. A method's _model is the 3D volume and its _data is the measured dataset for the same method.

Input	Formats	Loaded as
MT_model	ModEM/WS .rho	Resistivity volume
MT_data	ModEM .dat	Georeferences the mesh; Show Data draws the site locations
gravity_model	.xyz, .vox	Density volume, displayed in g/cc
gravity_data	.xyz	Show Data draws the survey points at their own elevation
magnetic_model	.xyz, .vox	Susceptibility volume
magnetic_data	.xyz	Show Data draws the survey points
seismic_data	SEG-Y	Seismic curtain and model drape
shapefiles	.shp	Linework, each entry with its own color, width and alpha

What you get depends on what you configure:

Configured	Result
Nothing	An empty 3D scene, sized to the shapefiles or seismic line if there are any
MT_model only	The model in its own local coordinates; georeferenced overlays are left out
MT_model + MT_data	Georeferenced into coordinate.target_crs
A gravity/magnetic model with an MT model	Resampled onto the MT cells, so the properties compare cell for cell
A gravity/magnetic model without one	Gridded on axes taken from its own coordinates

The property buttons switch which volume the scene, sections, isosurfaces and exports work on; a property with no file behind it reads N/A. Show Data overlays the measured data belonging to whichever property is on screen.

Reading point files

.xyz models and surveys are longitude latitude elevation value records, or easting/northing in any projected CRS. They are reprojected into the project CRS and, for models, resampled onto the scene's cells.

Source CRS detection

A file that states no CRS has one worked out for it. Degrees and projected metres never overlap in practice — longitude/latitude is bounded by ±180/±90, while a metric CRS puts survey data tens to hundreds of kilometres from its false origin — so a file is read as WGS84 lon/lat or as already being in the project CRS accordingly. When both columns fall inside ±90 and the lon/lat order is therefore ambiguous, the project CRS's declared area of use decides which column is longitude, so latitude-first files land in the right place too. .prj files and ModEM origins are still read from the file itself.

Demo datasets

scripts/generate_synthetic_data.jl writes four WGS84 lon/lat point files into Data/demo, derived from the demo ModEM mesh. None of them states a CRS, so loading them exercises the detection above:

File	Launcher input	Units	Records
density.xyz	gravity_model	kg/m³	37,044
susceptibility.xyz	magnetic_model	SI	37,044
gravity.xyz	gravity_data	mGal	7,056
magnetic.xyz	magnetic_data	nT	7,056

The two surveys are depth-weighted column integrals of the matching 3D model — enough to look like data flown over the same bodies, not a rigorous forward calculation.

A headless check that every launcher configuration builds a scene against the demo data:

julia --project=. scripts/startup_smoketest.jl

Faster Startup

If you want to remove most of the first-run compilation before a demo, build a custom sysimage once and launch TerraScope with it:

julia --project=. scripts/build_sysimage.jl
julia --project=. -J build/TerraScopeSysimage.dll examples/launch_TerraScope3D.jl

This does not eliminate file I/O, Windows display setup, or GL context creation, but it substantially reduces Julia compilation and makes startup more consistent across runs.

On Windows, you can also use the launcher in the repository root:

Launch-TerraScope.cmd

The launcher uses the sysimage automatically when it exists and offers to build it the first time.

Demo Data Generation

The four lon/lat .xyz files above are generated outside the runtime viewer, from the demo ModEM mesh:

julia --project=. scripts/generate_synthetic_data.jl

Example Output

  Activating project at `C:\Users\pmishra\OneDrive - Valtori GTK\Documents\Mac\GitHub\TerraScope.jl`

  ┌──────────────────────────────────────────────────────┐

▄▄▄▄▄▄▄▄▄                       ▄▄▄▄▄▄▄
▀▀▀███▀▀▀                      █████▀▀▀
   ███ ▄█▀█▄ ████▄ ████▄  ▀▀█▄  ▀████▄  ▄████ ▄███▄ ████▄ ▄█▀█▄
   ███ ██▄█▀ ██ ▀▀ ██ ▀▀ ▄█▀██    ▀████ ██    ██ ██ ██ ██ ██▄█▀
   ███ ▀█▄▄▄ ██    ██    ▀█▄██ ███████▀ ▀████ ▀███▀ ████▀ ▀█▄▄▄
                                                    ██
                                                    ▀▀
  └──────────────────────────────────────────────────────┘

  Let's look at diverse geophysical models together...
  Feedback / Issues → pankaj.mishra@gtk.fi
  Data directory    → C:\Users\pmishra\TerraScope.jl\Data\demo

  ✓  MT model        I_NLCG_140.rho
  ✓  MT data         I_NLCG_140.dat
  ✓  gravity model   density.xyz
  ✓  gravity data    gravity.xyz
  ✓  magnetic model  susceptibility.xyz
  ✓  magnetic data   magnetic.xyz
  ✓  seismic data    fire_updated.sgy
  ✓  shapefile       Tnew.shp

  › [███░░░░░░░░░░░░░░░░░░░░░░░░░░░]  11%  Loading MT model…
  › [███████░░░░░░░░░░░░░░░░░░░░░░░]  22%  Georeferencing…
  › [██████████░░░░░░░░░░░░░░░░░░░░]  33%  Loading gravity model…
  › [█████████████░░░░░░░░░░░░░░░░░]  44%  Loading magnetic model…
  › [█████████████████░░░░░░░░░░░░░]  56%  Loading measured data…
  › [████████████████████░░░░░░░░░░]  67%  Loading seismic section…
  › [███████████████████████░░░░░░░]  78%  Building 3D scene…
  › [███████████████████████████░░░]  89%  Opening viewer…
  ✓ [██████████████████████████████] 100%  Viewer ready

  ✓ TerraScope is ready. Close the window to exit.