NAME

M_PointSet — Agar-Math point set structures

SYNOPSIS

#include <agar/core.h>
#include <agar/gui.h>
#include <agar/math/m.h>

DESCRIPTION

The M_PointSet family of structures describe arbitrary sets of points in space. They are defined as follows:

/* Points in R^2 */
typedef struct m_point_set2 {
	M_Vector2 *p;
	Uint n, nMax;
} M_PointSet2;

/* Points in Z^2 */
typedef struct m_point_set2i {
	M_Real w, h;
	int *x, *y;
	Uint n, nMax;
} M_PointSet2i;

/* Points in R^3 */
typedef struct m_point_set3 {
	M_Vector3 *p;
	Uint n, nMax;
} M_PointSet3;

/* Points in Z^3 */
typedef struct m_point_set3i {
	M_Real w, h, d;			/* Scaling factor */
	int *x, *y, *z;
	Uint n, nMax;
} M_PointSet3i;

The points in a M_PointSet[23] are stored under the p array of vectors (see M_Vector(3)).

The points in M_PointSet[23]i are stored as separate arrays of integers x, y, z. The w, h and d members specify scaling factors to use when converting from an integer set to a real set.

INITIALIZATION

void
M_PointSetInit2(M_PointSet2 *S);

void
M_PointSetInit3(M_PointSet3 *S);

void
M_PointSetInit2i(M_PointSet2i *S, M_Real w, M_Real h);

void
M_PointSetInit3i(M_PointSet3i *S, M_Real w, M_Real h, M_Real d);

int
M_PointSetAlloc2(M_PointSet2 *S, Uint n);

int
M_PointSetAlloc3(M_PointSet3 *S, Uint n);

int
M_PointSetAlloc2i(M_PointSet2i *S, Uint n);

int
M_PointSetAlloc3i(M_PointSet3i *S, Uint n);

void
M_PointSetFree2(M_PointSet2 *S);

void
M_PointSetFree3(M_PointSet3 *S);

void
M_PointSetFree2i(M_PointSet2i *S);

void
M_PointSetFree3i(M_PointSet2i *S);

M_PointSet2
M_PointSetRead2(AG_DataSource *ds);

void
M_PointSetWrite2(AG_DataSource *ds, const M_PointSet2 *S);

M_PointSet3
M_PointSetRead3(AG_DataSource *ds);

void
M_PointSetWrite3(AG_DataSource *ds, const M_PointSet3 *S);

M_PointSet2i
M_PointSetRead2i(AG_DataSource *ds);

void
M_PointSetWrite2i(AG_DataSource *ds, const M_PointSet2i *S);

M_PointSet3i
M_PointSetRead3i(AG_DataSource *ds);

void
M_PointSetWrite3i(AG_DataSource *ds, const M_PointSet3i *S);

M_PointSet2
M_POINT_SET2_EMPTY(void);

M_PointSet3
M_POINT_SET3_EMPTY(void);

M_PointSet2i
M_POINT_SET2I_EMPTY(void);

M_PointSet3i
M_POINT_SET3I_EMPTY(void);

The M_PointSetInit[23]() functions initialize a point set in R^2 or R^3 to the null set.

The M_PointSetInit[23]i() functions initialize a point set in Z^3 or Z^3 to the null set. The w, h, d arguments specify the scaling factor to use when converting from an integer to a real point set.

The M_PointSetAlloc*() functions allocates memory for the specified number of points, returning 0 on success or -1 if insufficient memory is available.

The M_PointSetFree*() functions free the point sets, clearing the arrays and reinitializing the point count to 0.

The M_PointSetRead*() and M_TriangleWrite*() functions read or write a triangle structure from/to an AG_DataSource(3).

The macros M_POINT_SET*_EMPTY() expand to static initializers for any of the M_PointSet structures.

OPERATIONS

int
M_PointSetAdd2(M_PointSet2 *S, M_Vector2 v);

int
M_PointSetAdd3(M_PointSet3 *S, M_Vector3 v);

int
M_PointSetAdd2i(M_PointSet2 *S, int x, int y);

int
M_PointSetAdd3i(M_PointSet3i *S, int x, int y, int z);

int
M_PointSetCopy2(M_PointSet2 *D, const M_PointSet2 *S);

int
M_PointSetCopy3(M_PointSet3 *D, const M_PointSet3 *S);

int
M_PointSetCopy2i(M_PointSet2i *D, const M_PointSet2i *S);

int
M_PointSetCopy3i(M_PointSet3i *D, const M_PointSet3i *S);

void
M_PointSetSort2(M_PointSet2 *S, enum m_point_set_sort_mode2);

void
M_PointSetSort3(M_PointSet3 *S, enum m_point_set_sort_mode3);

The M_PointSetAdd*() functions insert a new point at the end of the set S. On success, the index of the new point is returned. If insufficient memory is available, -1 is returned.

The M_PointSetCopy*() functions copy the contents of source set S into destination set D, returning 0 on success or -1 if insufficient memory is available.

The M_PointSetSort[23]() functions sort the point sets by point coordinate. The mode arguments specify the sorting mode:

enum m_point_set_sort_mode2 {
	M_POINT_SET_SORT_XY,
	M_POINT_SET_SORT_YX,
};
enum m_point_set_sort_mode3 {
	M_POINT_SET_SORT_XYZ,
	M_POINT_SET_SORT_XZY,
	M_POINT_SET_SORT_YXZ,
	M_POINT_SET_SORT_YZX,
	M_POINT_SET_SORT_ZXY,
	M_POINT_SET_SORT_ZYX,
};

HISTORY

The M_PointSet family of structures first appeared in Agar 1.4.2.