*.shp file is a kind of shape definition file which can be created by a text editor or word processor that enables you to save in ASCII format. In this shape definition file you can either define a font or a shape.
*.shx file is a kind of compiled shape file that can be imported by CAD software directly such as AutoCAD and Zwcad and so on.
How to use *.shp file?
Firstly, the COMPILE command compiles a SHP file and generates a SHX file.
And then, if you defines a font in the SHP file, use the STYLE command to define a text style and use one of the text placement commands (TEXT or MTEXT) to place the characters in the drawing. If you defines shapes in the SHP file, use the LOAD command to load the relative compiled shape file(SHX file) into the drawing and use the SHAPE command to place the individual shapes in the drawing (similar in concept to the INSERT command).
ZWCAD doesn't support COMPILE command at present.
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