Development of an extension for PostgreSQL and PostGIS

Hello.

I will start developing an extension to PostgreSQL next to PostGIS using the C language.

If my new type were:

CREATE TYPE mytype (.., .., .., geom geometry);

The creation of the structure in c, would be something like?

#include "liblwgeom.h"

Struct mytype
{
Int32 id;
LWGEOM lwgeom;

};

In the extension I will create new data types for PostgreSQL, but I would like to use the geometric objects that the PostGIS extension offers, such as POINT, LINE, POLYGON, etc. In addition to their input functions (wkt- ST_GeomFromText ()), operators, index, etc.

In this case just importing the liblwgeom library would be enough to develop an extension to PostgreSQL / PostGIS?

Would you have any examples of such a project?

Thanks in advance!!