I have one drawing in 3D. All the objects in the drawing are in 3D. I want to convert those entities in 2D. I have checked the SECTIONPLANE command in AutoCAD. How can I use this command programatically to cut those 3D entities and get the 2D entities from it. Is there any other method to get 2D entities from 3D?
you can glance at AsdkHlrApi - Hidden Line Removal - (provided along with objectarx utils/hlrapi folder), this API is able, for instance, to create 2d drawing primitives (lines, arcs, ) that represent 3d/2d entities given a viewport information, these primitives are provided along with their visibility status (hidden lines).
you can find hlrapi samples in oarx_root/utils/hlrapi/sample folder.