An addon to import a vector as raster layer in GRASS GIS

Import a vector layer, e.g., a Geopackage, as raster layer in GRASS GIS with the v.in.rast addon. The addon uses gdal_rasterize to convert the vector layer to a geoTIF. Next, it imports the geoTIF into GRASS, ensuring that the extent and resolution of the imported data align with those of the computational region.

One of the strengths of GRASS GIS is its topological vector model (see more here). However, this strength comes with a drawback: importing large and complex vector layers can be time-consuming. I often import a vector layer only to convert it to a raster layer for further analysis. In such cases, it can be quicker to convert the vector layer to a raster outside GRASS, using tools like QGIS or gdal_rasterize, and then import the resulting raster layer.

To streamline this process and leverage the powerful region functionality in GRASS, I created a small addon, v.in.rast, which allows direct import of a vector layer as a raster layer. The raster is generated using the resolution defined by the computational region. Users can choose to convert and import the entire vector or just the portion within the computational region’s extent. Refer to the manual page for additional options.

This approach can significantly reduce the time required for processing. For example, on my computer, importing a vector layer with 53,624 buildings and converting it to a raster took about 37 seconds (35 seconds to import the vector layer and 2 seconds to convert it to a raster). Using v.in.rast to convert and import the vector layer as a raster took only 6 seconds.