Practical GIS

Vectorizing suitable areas

Now that we have an appropriate suitability value, we can vectorize our suitability map. We've already seen how vector-raster conversion works, but we did not encounter raster-vector conversion. As every raster layer consists of cells with fixed width and height values, the simplest approach is to convert every cell to a polygon. GDAL uses this approach, but in a more sophisticated way. It automatically dissolves neighboring cells with the same value. In order to harness this capability, we should provide a binary layer with zeros representing non-suitable cells, and ones representing suitable cells:

1. Open a raster calculator, and create a binary layer with a conditional expression using the minimum suitability ...