The program is a viewer and editor for:
GDSII files (tree of structures containing polygons and polylines on layers).
KEY files (own made extended GDSII in ascii format)
supports : circles, arcs, text, polygons(including arc segments), polylines(including arc segments) , boxes, structures, references to structures, all with a width parameter,
user defined properties to primitives and structures.
DAVID MANN files (david man flash format for mask plotting)
Mainly the program is used in the electronic chip design industry. But it it offers much more then that. Many effort has gone in automating the jobs to be done.
Therefore the commands isued by the GUI, go through a command interpreter as ASCII strings, in order to record them and replay it them afterwords.
Features:

It allows to draw primitives on a chosen layer, and to manipulate them. A (limited) undo mechanism is available to support this.
stack oriented tools allows zooming while drawing new primitives and editing them. This also makes it possible to draw extremely accurate.
primitives on the layers or/can be transparent
colors and fill patterns can be set on a layer basis
drawing order of layers can be changed
a hiearchy of pictures, named structures, can be handled and manipulated seperately
saving as a bitmap and other formats.
measuring distances
adding user defined properties to primitives
Next to this it contains several algorithms for performing 2D polygon operations (boolean, offset, arc recognition etc.). All the primitives are situated on layers. The operations take two sets of layers (each set containing all primitives on the selected layers). The sets are the operands of the (boolean) operation, a destination layer is chosen to contain the result of the operation.
Operation:

boolean OR AND EXOR A-B B-A
positive and negative process offset
circle recognition in polygon and polyline data.
move copy delete etc.
transformations (scaling , rotation , moving)
flatten the hiearchy of the drawing
drivers for CNC (laser and milling machinery)