Shape preserving properties of some operations on binary pictures

Two algorithms for propagation and rotation of 2-D objects are proposed. These geometric operations have certain important shape-preserving properties. The factor of propagation and the angle of rotation can be arbitrary. An extension of these algorithms from 2-D to 3-D is possible, using voxels rather than pixels; the shape-preserving properties of propagation and rotation in 3-D are similar to the Z-D properties