CAD Tips

Pedro Gerstberger e-mailed a request to export x,y,z points from either polylines or AutoCAD point entities. The AutoLISP solution plist.lsp lets you select lightweight polylines, 2D polylines, or point objects, then makes a comma-delimited text file suitable for opening in Microsoft Excel.

plist.lsp lists the points grouped in this order: lightweight polylines, 2D polylines, and point objects. Figure 1 shows an AutoCAD drawing with an assortment of polyline types and some point entities. Figure 2 shows a Microsoft Excel worksheet that displays the x,y,z locations of points selected from the drawing in Figure 1.
I wrote an AutoLISP Solution more than two years ago (Cadalyst, July 2000) that extracted the vertex points from polylines. That program, vertext.lsp, was suitable for early versions of AutoCAD. This month's solution is an update that includes polylines and point entities and uses the more modern approach of object-oriented programming with ActiveX objects, methods, and properties.