Coming from…

Coming from QGIS or ArcGIS Pro

If you build models in QGIS or ArcGIS Pro, Locra works like a Model Builder that is also a data-prep tool. Each geoprocessing step is a node, attribute work and spatial work sit in the same workflow, and everything runs on your machine, offline if you need it to.

What feels familiar

Your file formats. A Geo Reader opens GeoJSON, Shapefile, GeoPackage, GML and KML/KMZ, and GeoParquet comes in through the Parquet reader. A GeoPackage with several layers lists each layer in the Drones panel. Write Geo File writes GeoJSON, GeoPackage, Shapefile or GeoParquet.
Projections. The Metadata tab shows a layer's CRS. Reproject transforms geometry to another CRS, and the Geo Reader can reproject as it reads.
Overlay and proximity. Spatial join, buffer, clip, intersect, dissolve and Voronoi each have a node.
Hex grids. H3 Aggregate bins features into H3 hexagons.
A map for every step. Select a node and open the Map tab under the canvas. It draws features, choropleths, heatmaps, proportional symbols, bivariate choropleths, 3D extrusions, clusters and flow lines.

What's different

Vector and tables only. There is no raster or mesh data, and geometries are 2D.
Geocoding and routing run offline. Geocode matches place names against a bundled gazetteer, and street addresses against an address index you build for your region. Route, Isochrone and Matrix use road tile sets you build the same way. Both are managed on one settings page.
Offline basemaps. The Map tab's basemap can come from a file on your machine. Its selector offers Auto, Off, Offline and Online, and Offline never touches the network.
No layer styling panel. You style a node's map in its Map tab. To keep a map for a report, add a Map node.
Sources are never edited. Nodes read from a layer and write new outputs. To drop features, filter them on the way through.

GIS names in Locra

You don't need this table open while you work. Type a QGIS or ArcGIS name into the add-node menu (right-click the canvas) or the command palette (⌘K, Ctrl+K on Windows). The matching Locra node shows up with a small chip, such as GIS: Buffer, so you learn our name as you go.

Data in and out

GIS name	Locra
Excel To Table	Excel Reader
GPX To Features	Geo Reader (drop the .gpx file on the canvas)
XY Table To Point	Make Point
Create points layer from table	Make Point
KML To Layer	Geo Reader (drop the .kml or .kmz file on the canvas)
Export Features	Write Geo File
Save vector features to file	Write Geo File
Feature Class To Shapefile	Write Geo File
Export To Parquet	Write Parquet or Write Geo File
Export to PostgreSQL	Write to DB
Create Database Connection	DB Reader
Execute SQL	DuckDB Query
Download file via HTTP(S)	REST Fetch or HTTP Request

Attributes and tables

GIS name	Locra
Field calculator	Add Column
Calculate Field	Add Column
Alter Field	Rename or Cast Types
Delete Field	Select Columns
Refactor fields	Rename or Cast Types
Select By Attributes	Filter
Extract by expression	Filter
Add Join	Join or Lookup
Join Field	Lookup or Join
Summary Statistics	Aggregate
Frequency	Value Counts or Aggregate
Pivot Table	Pivot
Transpose Fields	Unpivot
Reclassify Field	Bin
Add Incrementing ID Field	Add Row Number

Overlay and proximity

GIS name	Locra
Buffer	Buffer
Multiple Ring Buffer	Trade Areas or Buffer
Clip	Spatial Intersection
Intersect	Spatial Intersection
Erase	Spatial Intersection
Union	Spatial Intersection for the overlaps and its difference mode both ways, then Union to stack the pieces
Dissolve	Dissolve, or Aggregate's Union (dissolve) to keep statistics per group
Spatial Join	Spatial Join
Join attributes by location	Spatial Join
Join attributes by nearest	Spatial Join
Select by location	Spatial Join
Near	Spatial Join
Count points in polygon	Spatial Join or Aggregate
Summarize Within	Spatial Join or Aggregate
Tabulate Intersection	Spatial Intersection or Spatial Measure

Geometry

GIS name	Locra
Project	Reproject
Define projection	DuckDB Query or Reproject
Repair Geometry	Make Valid
Calculate Geometry Attributes	Spatial Measure
Multipart To Singlepart	Poly Split
Delete holes	Remove Holes
Minimum bounding geometry	Poly Build
Points To Line	Poly Build
Voronoi polygons	Voronoi
Simplify	DuckDB Query
Centroids	DuckDB Query

Density, grids and interpolation

GIS name	Locra
Generate Tessellation	H3 Aggregate
Aggregate Points	Spatial Join or H3 Aggregate
Kernel Density	H3 Aggregate or Spatial Interpolate
IDW Interpolation	Spatial Interpolate
Spatial Outlier Detection	Outlier Flag (outliers in a column, not in space)

Geocoding, routing and trade areas

GIS name	Locra
Geocode Addresses	Geocode
Reverse Geocode	Reverse Geocode
Route	Route or Optimize stops
Service Area	Isochrone or Trade Areas
OD Cost Matrix	Matrix
Closest Facility	Matrix or Spatial Join
Solve Vehicle Routing Problem	Optimize stops
Snap Tracks	Map-match
Generate Drive Time Trade Areas	Trade Areas or Isochrone
Generate Trade Area Rings	Trade Areas
Enrich	Population (Kontur) or US Census (ACS)
Huff Model	Gravity Model, fitted with Calibrate Gravity Model

Maps, layouts and running models

GIS name	Locra
Attribute Table	The Data tab under the canvas
Zoom To Layer	The Map tab under the canvas
Color Coded Layer	Map
Export print layout as PDF	Write Report or Report Assembly
Run Model	The Run button (`⌘↵`), or Run pipeline in `⌘K`
Schedule	Deploy & schedule to cloud (Cloud runs)
Export as Python Script	Export as Python library
Geoprocessing History	Version history
Auto Layout	Tidy graph (`⇧A`) re-flows the layout

No equivalent yet

Some QGIS or ArcGIS tools have no Locra node yet. Searching for them shows a hint instead of an empty list. These are the ones you are most likely to miss:

GIS name	What to do instead
Aspect	Raster data isn't supported; vector and tables only
Export mesh faces	Mesh layers aren't supported
Set Z value	Z/M values aren't supported; geometries are handled as 2D
Create Routes	Linear referencing isn't supported
Sliver polygons	Topology checks aren't supported yet
DBSCAN clustering	Spatial clustering isn't supported yet
Hot Spot Analysis (Getis-Ord Gi*)	Hot spot statistics aren't supported yet; H3 Aggregate shows density
Spatial Autocorrelation (Global Moran's I)	Spatial autocorrelation isn't supported yet
Create Random Points	Random point generation isn't supported yet
Densify by interval	No vertex densify; write it in a DuckDB Query
Location-Allocation	Not supported yet; Matrix gives the travel costs to start from
Layer To KML	KML export isn't supported; Write Geo File writes GeoJSON/GPKG
Feature Class To Geodatabase	File geodatabase isn't written; Write Geo File to GeoPackage
Export To CAD	CAD/DXF export isn't supported; Write Geo File for GIS formats
Write vector tiles (MBTiles)	Vector tile export isn't supported
Geographically Weighted Regression (GWR)	Only global OLS: Linear Regression; no GWR yet
Delaunay triangulation	No triangulation node; Voronoi builds the dual polygons
Single sided buffer	One-sided buffers aren't supported; Buffer grows both sides

Tips

Search with your tool names. Pairwise Clip, Join attributes by location and Create Thiessen Polygons all find their Locra node.
Check the CRS early. Select a reader and look at the Metadata tab. If layers don't line up, add Reproject before the join, or set Reproject to on a Geo Reader.
Install offline data before you go offline. Street-level geocoding and road routing need an address index and a road tile set for your region. Build them on the offline map data settings page while you have a connection.
Write SQL for the long tail. Many vertex and geometry tools, such as centroids, simplify or extract vertices, map to a DuckDB Query node, where DuckDB's spatial functions do the work.
Pull in context data. Overture Maps, OSM Overpass and Population (Kontur) add places, roads, buildings and population to your study area.