Using the VLShape class

The VLShape class provides a convenient and concise way to access data within a vector layer. For example, the following script checks the vertex lists of all the shapes, and if the first and last vertex do not match, it adds an extra vertex to the end of the list matching the first vertex, thus ensuring each shape represents a closed area. The height or z value of the vertices is ignored. Note also that errors are trapped, and the script ensures the file is correctly closed if an error does occur.

try
  local VLShape shape
  local Vertex v
  local integer n
  call shape.Open( "irvine.pix", 25,"w" )
  call shape.First()
  while ( shape.AtEnd != "TRUE" )
    n = shape.numvertices
    if ( n > 0 AND \
       ( shape.vertices[1].x != shape.vertices[n].x OR \
         shape.vertices[1].y != shape.vertices[n].y ) ) then
       v.x = shape.vertices[1].x
       v.y = shape.vertices[1].y
       call shape.AddVertex( v )
    endif
    call shape.Next()
  endwhile
  call shape.Close()
onerror
  call shape.Close()
  print getlasterrormessage()
  call EASIError( 800, "Failed to close shapes!" )
endonerror