Abstract: A processor for image processing in accordance with shadow polygons defining together a current shadow volume is configured to determine a set of tiles, each tile being formed of a set of pixels and having a respective tile volume defined by the set of pixels and depth values relating to the set of pixels. The processor is further configured to determine whether a tile is a potential boundary tile or a non-boundary tile, a potential boundary tile having a tile volume intersected by at least one of the shadow polygons. A method and device for image processing are also discussed.