Grid Outline

Use the Grid and Image > Utilities > Grid Outline menu option or the Grid Knitting > Grid Outline menu option, (GRID2PLY GX), to find edge points in a grid image, and either save the edges in a polygon file or draw the edges on the current map.

Grid Outline dialog options

Grid file

Name of the grid file to find edge points

Script Parameter: GRID2PLY.GRID

Action

"Draw on current map" to draw the edge on the current map.
"Save to a file" to save the edge coordinates in a polygon file.

The next dialog presented depends on the action selected.

Script Parameter: GRID2PLY.ACTION
If the first letter is "D", the polygon is drawn to the current map.

Minimum polygon size (points)

Minimum polygon size limit.

Default is 0 points (all polygons) – This can help work with very large grids with a very large number of islands. It will ignore polygons of less than x points.

Script Parameter: GRID2PLY.MINPOINTS

Save Edges in a Polygon File

Polygon file name (.ply)

A polygon (.ply) file name

Script Parameter: GRID2PLY.PLY

Save mode

"New file" to save in a new file.
"Append" to append to an existing polygon file.

Script Parameter: GRID2PLY.MODE

Edge resolution (cells)

Edge resolution for thinning.

Default is 1 cell – no thinning. EdgeRes> 1 will thin the edge points to resolve the edge to a courser sample.

Script Parameter: GRID2PLY.EDGERES (Default 1.0)

Draw Grid Edge on the Map

Line colour

Select a line colour

Script Parameter: GRID2PLY.LCOLOR

Fill colour

Select a fill colour

Script Parameter: GRID2PLY.FCOLOR

Line thickness (mm)

The thickness of the edge line in mm.

Script Parameter: GRID2PLY.THICK

Line style

Select a line style from the list.

Script Parameter: GRID2PLY.STYLE

Style pitch (mm)

For styled lines, specify the style pitch.

Script Parameter: GRID2PLY.PITCH

Edge resolution (cells)

Edge resolution for thinning, in mm. Use of this parameter will reduce the map size for complex edges plotted at large scales.

Default is 0.2mm. To disable edge thinning, set to a negative value.

Script Parameter: GRID2PLY.EDGERESMAP (Default 0.2)

Application Notes

Only the outside edge of the first encountered non-dummy area of the grid isoutlined. Holes and islands are not recognized.

If saving the grid outline to a polygon file, the polygon file can be used for the following purposes:

• As a mask outline by the masking functions.

• To be drawn on maps using the POLYDRAW GX.

• For use by other programs.

Parameter Edge Resolution is for edge thinning action, i.e. to remove "colinear" points outside of this specified resolution to resolve the edge to a courser sample.

Thinning is disabled for map output when set to less than zero (0.0), and is applied for output to a file only if set to larger than the "X" cell size.