I am working on QGIS with a shapefile:
I transform it through Raster-> Conversion-> Polygonize
Then I eliminate some parts (Sea), and those that are bigger than one single square of grid but are inside of the mainland
I would like to fill those black gaps with no grid in the vector file with a grid of the same size of all the other squares. I'm working on this trying to use the final polygon as a model to cut other shapefiles.