This is a feature request for either a new pool element type with a condition field, or an addition of an optional condition field to the delegating pool element type, which in both cases would impose placement conditions onto individual jigsaw pieces.

Some of the placement conditions could potentially have additional options when used in context of pool elements, for example:

• radious field of the grid condition could be set to contained to limit the grid to the bounding box of the jigsaw piece.
• offset could have values center, origin and root, to specify the offset at, respectively: the center of the piece's bounding box, location of its jigsaw block, and the origin position of the whole structure.