Agar

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SYNOPSIS

#include <agar/math.h>

DESCRIPTION

The M_PointSet family of structures describe arbitrary sets of points in space. They are defined as follows: 
/* Points in R2 */
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 R3 */
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 R2 or R3 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,
};

SEE ALSO

AG_DataSource(3), AG_Intro(3), M_Circle(3), M_Geometry(3), M_Plane(3), M_Polygon(3), M_Rectangle(3), M_Sphere(3), M_Triangle(3), M_Vector(3)

HISTORY

The M_PointSet family of structures first appeared in Agar 1.4.2
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