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# SYNOPSIS

 ```#include #include #include ```

# DESCRIPTION

The Agar-Math library implements a number of algorithms and operations on related to geometrical structures. The following basic structures are defined, see their respective manual pages for more details:
 M_Line(3) Line segment or ray in R2 (M_Line2) or R3 (M_Line3). M_Circle(3) Circle in R2 (M_Circle2) or R3 (M_Circle3). M_Sphere(3) Sphere in R3. M_Plane(3) Plane in R3 (M_Plane). M_Triangle(3) Triangle in R2 (M_Triangle2) or R3 (M_Triangle3). M_Rectangle(3) Rectangle in R2 (M_Rectangle2) or R3 (M_Rectangle3). M_Polygon(3) Polygon in R2. M_Polyhedron(3) Polyhedron in R3.

# GENERIC GEOMETRIC ENTITIES

A number of routines (e.g., computation of intersections) return sets of zero or more geometrical structures of different types, depending on the

The M_Geom2 structure defines a geometrical entity in R2:
 ```typedef struct m_geom2 { M_GeomType type; union { M_Vector2 point; M_Line2 line; M_Circle2 circle; M_Triangle2 triangle; M_Rectangle2 rectangle; M_Polygon polygon; } g; } M_Geom2; ```

Similarly, M_Geom3 defines an entity in R3:
 ```typedef struct m_geom3 { M_GeomType type; union { M_Vector3 point; M_Line3 line; M_Circle3 circle; M_Triangle3 triangle; M_Rectangle3 rectangle; M_Polygon polygon; M_Sphere sphere; M_Plane plane; M_Polyhedron polyhedron; } g; } M_Geom3; ```

The type field can take on the following values:
 M_NONE Undefined type M_POINT An M_Vector2(3) or M_Vector3(3). M_LINE An M_Line2(3) or M_Line3(3). M_CIRCLE An M_Circle2(3) or M_Circle3(3). M_POLYGON An M_Polygon(3). M_TRIANGLE An M_Triangle2(3) or M_Triangle3(3). M_RECTANGLE An M_Rectangle2(3) or M_Rectnagle3(3). M_SPHERE An M_Sphere(3). M_PLANE An M_Plane3(3).

# GENERIC GEOMETRIC ENTITIES: SETS

Sets of generic geometric entities in R2 are described by the structure:
 ```typedef struct m_geom_set2 { M_Geom2 *g; Uint n; } M_GeomSet2; ```
Similarly for R3:
 ```typedef struct m_geom_set3 { M_Geom3 *g; Uint n; } M_GeomSet3; ```

The following routines allow the manipulation of these sets.

 M_GeomSet2 M_GEOM_SET_EMPTY (void)M_GeomSet3 M_GEOM_SET_EMPTY (void)void M_GeomSetAdd2 (M_GeomSet2 *S, const M_Geom2 *g)void M_GeomSetAdd3 (M_GeomSet3 *S, const M_Geom3 *g)void M_GeomSetFree2 (M_GeomSet2 *S)void M_GeomSetFree3 (M_GeomSet3 *S)

The M_GEOM_SET_EMPTY() macro is provided as a static initializer for M_GeomSet2 and M_GeomSet3.

The M_GeomSetAdd2() and M_GeomSetAdd3() functions insert a copy of the entity g into the geometric set S.

M_GeomSetFree2() and M_GeomSetFree3() release the resources allocated by a geometric set.  