All DataStore in Apache SIS provides their data as a collection of `Resource`. There is different kinds of resources; SIS 0.8 already provides FeatureSet for resources made of a stream of `Feature` instances (typically geometries associated to some property values). We need another specialization of resources, GridCoverageResource, for raster data. Two key elements of grid coverages are:
- GridGeometry, which describe the domain of a coverage (e.g. the raster size in pixels and the geographic envelope).
- SampleDimension which describe the range of a coverage (e.g. the meaning of values stored in raster bands).