next up previous index
Next: Logic and algorithm Up: GEOM020 ` MANY' Previous: Topological extensions via

Divisions along arbitrary axis

As protuding MANY daughters are automatically clipped by their mother, it is possible to divide objects along arbitrary directions. Suppose for example that we want to divide a PCON into planar slices parallel to the plane X + Y = 0; it is enough to position a MANY BOX embedding completely the PCON `inside' the PCON itself; the BOX must be rotated of 45 degrees in X and Y and then divided along one of its natural axis. Another example can be the following: suppose we want to divide 24 times in PHI a PGON with only 6 natural segmentations in PHI; then we have to position a MANY TUBE, completely embedding the PGON, `inside' the PGON itself; again, we can now divide the tube in 24 slices in PHI and the tracking will see only the PGON divided 24 times in PHI. Reduction of 2D structure to 1D structure.

Sometimes there are complicated multidimensional geometrical structures (like honeycombs, spaghetti, etc.) which can be reduced to the overlap of several one-dimensional patterns (for which divisions can be used or virtual divisions are particularly efficient). The MANY option allows to superimpose such 1D structures to reproduce the multi-dimensional ones in a very effective way, instead of positioning the volumes one by one in the 2D or 3D pattern. The following picture will explain better this concept.


Janne Saarela
Mon Apr 3 12:46:29 METDST 1995