3x3 matrix functions

Macros
#define	Mat3Add(a, b, c)
#define	Mat3Blend(m1, m2, b, m)
#define	Mat3CompMult(a, b, c)
#define	Mat3Copy(a, b)
#define	Mat3Expand(a)
#define	Mat3Identity(a)
#define	Mat3MultAdd(a, s, b, c)
#define	Mat3Scale(a, b, c)
#define	Mat3Subtract(a, b, c)
#define	Mat3Trace(a)   ((a)[0] + (a)[4] + (a)[8])
#define	Mat3Zero(a)   memset ((a), 0, 9 * sizeof (a)[0])
#define	Mat4toMat3(a, b)

Functions
int	Mat3Decompose (const mat4_t mat, quat_t rot, vec3_t shear, vec3_t scale)
	Decompose a 3x3 column major matrix into its component transformations. More...
vec_t	Mat3Determinant (const mat3_t m)
void	Mat3Init (const quat_t rot, const vec3_t scale, mat3_t mat)
int	Mat3Inverse (const mat3_t a, mat3_t b)
void	Mat3Mult (const mat3_t a, const mat3_t b, mat3_t c)
void	Mat3MultVec (const mat3_t a, const vec3_t b, vec3_t c)
void	Mat3SymEigen (const mat3_t m, vec3_t e)
void	Mat3Transpose (const mat3_t a, mat3_t b)

Detailed Description

Macro Definition Documentation

#define Mat3Add	(		a,
			b,
			c
	)

Value:

do { \
		VectorAdd ((a) + 0, (b) + 0, (c) + 0); \
		VectorAdd ((a) + 3, (b) + 3, (c) + 3); \
		VectorAdd ((a) + 6, (b) + 6, (c) + 6); \
    } while (0)

#define Mat3Blend	(		m1,
			m2,
			b,
			m
	)

Value:

do { \
		VectorBlend ((m1) + 0, (m2) + 0, (b), (m) + 0); \
		VectorBlend ((m1) + 3, (m2) + 3, (b), (m) + 3); \
		VectorBlend ((m1) + 6, (m2) + 6, (b), (m) + 6); \
    } while (0)

#define Mat3CompMult	(		a,
			b,
			c
	)

Value:

do { \
		VectorCompMult ((a) + 0, (b) + 0, (c) + 0); \
		VectorCompMult ((a) + 3, (b) + 3, (c) + 3); \
		VectorCompMult ((a) + 6, (b) + 6, (c) + 6); \
    } while (0)

#define Mat3Copy	(		a,
			b
	)

Value:

do { \
		VectorCopy ((a) + 0, (b) + 0); \
		VectorCopy ((a) + 3, (b) + 3); \
		VectorCopy ((a) + 6, (b) + 6); \
    } while (0)

#define Mat3Expand

(

a

)

Value:

VectorExpand ((a) + 0), \
	VectorExpand ((a) + 3), \
	VectorExpand ((a) + 6)

#define Mat3Identity

(

a

)

Value:

do { \
		Mat3Zero (a); \
        (a)[8] = (a)[4] = (a)[0] = 1; \
    } while (0)

#define Mat3MultAdd	(		a,
			s,
			b,
			c
	)

Value:

do { \
		VectorMultAdd ((a) + 0, s, (b) + 0, (c) + 0); \
		VectorMultAdd ((a) + 3, s, (b) + 3, (c) + 3); \
		VectorMultAdd ((a) + 6, s, (b) + 6, (c) + 6); \
    } while (0)

#define Mat3Scale	(		a,
			b,
			c
	)

Value:

do { \
		VectorScale ((a) + 0, (b), (c) + 0); \
		VectorScale ((a) + 3, (b), (c) + 3); \
		VectorScale ((a) + 6, (b), (c) + 6); \
    } while (0)

#define Mat3Subtract	(		a,
			b,
			c
	)

Value:

do { \
		VectorSubtract ((a) + 0, (b) + 0, (c) + 0); \
		VectorSubtract ((a) + 3, (b) + 3, (c) + 3); \
		VectorSubtract ((a) + 6, (b) + 6, (c) + 6); \
    } while (0)

#define Mat3Trace

(

a

)

((a)[0] + (a)[4] + (a)[8])

#define Mat3Zero

(

a

)

memset ((a), 0, 9 * sizeof (a)[0])

#define Mat4toMat3	(		a,
			b
	)

Value:

do { \
		VectorCopy ((a) + 0, (b) + 0); \
		VectorCopy ((a) + 4, (b) + 3); \
		VectorCopy ((a) + 8, (b) + 6); \
    } while (0)

Function Documentation

int Mat3Decompose	(	const mat4_t	mat,
		quat_t	rot,
		vec3_t	shear,
		vec3_t	scale
	)

Decompose a 3x3 column major matrix into its component transformations.

This gives the matrix's rotation as a quaternion, shear (XY, XZ, YZ), and scale. Using the following sequence will give the same result as multiplying v by mat.

QuatMultVec (rot, v, v); VectorShear (shear, v, v); VectorCompMult (scale, v, v);

vec_t Mat3Determinant

(

const mat3_t

m

)

void Mat3Init	(	const quat_t	rot,
		const vec3_t	scale,
		mat3_t	mat
	)

int Mat3Inverse	(	const mat3_t	a,
		mat3_t	b
	)

void Mat3Mult	(	const mat3_t	a,
		const mat3_t	b,
		mat3_t	c
	)

void Mat3MultVec	(	const mat3_t	a,
		const vec3_t	b,
		vec3_t	c
	)

void Mat3SymEigen	(	const mat3_t	m,
		vec3_t	e
	)

void Mat3Transpose	(	const mat3_t	a,
		mat3_t	b
	)