SpaTools: Cut Polygon in AutoCAD










Cutting a Polygon into Two Parts is a frequent operation used in GIS environments such as ArcGIS and QGIS for real estate, land development, cartography, parcel mapping applications.




In cad environment, it is little bit tricky to cut a polygon into two polygons. A command named as “MPSPLIT” was introduced in AutoCAD Map which cuts a MPOLOYGON object into two polygons. MPPOLYGON is not an ordinary polygon but rather a special object created for AutoCAD MAP and CIVIL 3D. MPSPLIT requires a MPPOLYGON object which can be created by converting a simple closed polyline using command MAPPOLYLINETOPOLYGON.

In order to cut an ordinary polygon, Let me introduce a new tool (CUTPOLYGON) as part of SpaTools which can cut a polygon (closed polyline) into exactly two polygons.  The workflow of CutPolygon can be understood from the following animations.






Just enter CUTPOLYGON command on command prompt. Select the source polygon and a cutting line. If you want to delete the source polygon, simply enter it by default value of Yes otherwise type N to retain the original source polygon.

This tool can be useful when dividing the lots of land into parcels, digitizing the parcels for parcel mapping and many more applications in cartography under Autocad environment. 

The cutting edge is just a line segment intersecting the polygon at two points dividing the polygon into exactly two parts, but I intend to extend it for cutting polygon by a polyline comprising of multiple line segments. 

The updated SpaTools DLL can be downloaded from Cadomation. Give your feedback and suggestions for new tools in comments.

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Note: Read the previous blog if there is any error in loading using Netload. 

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