                                                                vertex_thin 
Chapter 10 Map Manipulation

The vertex_thin command will remove vertices controlled by a user input radius
and set number.  Smoothing is also allowed.  Nodes (intersection of two or more
line segments) will not be moved or removed.  Only the vector (not the raster)
is modified.  This command operates only on map data, not on imported vector
data (not data on levels 32-95).

vertex_thin

    Reduces vectorized data.
     
*        vertex_thin s c r m

    Reduces vectorized data in set s by eliminating vertices based on a
*   tolerance (corridor radius) r.  r is in units of units code c.  All
    vertices that lie within distance r of a straight line (in raster
    coordinates) between trial endpoint vertices are eliminated.  Affects only
*   the vectorized data. Sharp corners can be rounded by ading verticies
*   smoothing.  Assembly required.  NOTE: do not confuse vertex_thin
    (which deletes vertices from vector files) with thin_lines (which erases
    pixels on the raster until raster lines are 1-pixel thick).  If the m
    parameter is non-zero, then vertices will be added to sharp corners to
    smooth them.
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    Options/arguments:

         s         Set number of objects to vertex_thin,
                   0-31
         c         Coordinate system code (see coord_type)
         r         radius of tolerance for vertex thinning.
*        m         smoothing code:  0 = none,  1 = round sharp corners
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    Example(s):

    To reduce the vector data in set 13 by eliminating the vertices which are
*   within 25 feet of one another without smoothing, enter:

*        vertex_thin 13 2 25 0
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    See also:

              assemble, vertex_move
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