http://innersoft.itspanish.org/en/

InnerSoft CAD is a plug-in for AutoCAD that installs a set of productivity tools for Civil and Survey engineering, Counting, Estimating and measurements in construction project budgets. You can:

Export to an Excel Sheet the values of Area/Length property or coordinates for various AutoCAD entities.
Import from an Excel Sheet the vertex coordinates for a set of 2D polylines or 3D polylines (you can choose between 3 different methods). You can also import a set of points from Excel or a set of Texts with an insertion point for each one.
Convert splines into polylines. Convert objects into polylines. Convert vertices of objects into points.
Extract all block definitions of a drawing in individual AutoCAD files (each block definition in a single file).
Sum the area or length property of a set of objects. Sum accumulated distance of a user defined walk in the drawing.
Draw the longitudinal profile of a terrain or set of surfaces. Triangulate a set of points or mesh a model surface.
Get measurements on AutoCAD drawings for construction project budgets.
Create, open or save different libraries, which contain a series of AutoCAD drawings (*.dxf or *.dwg) organized by books.
Draw a polyline graph, a 2D & 3D convex hull; lines, planes, circles and spheres by regression from a selection of points; clothoids, parabolas, circular transition curves and parabolic vertical transitions.