// NOTE: REPLACED ALL float'S WITH vec_t'S

// basic stuff

#include <time.h>
#include <math.h>
#include <stdlib.h>
#include <stdio.h>

#define M_PI 3.14159265358979323846f
#define DEG2RAD( a ) ( ( (a) * M_PI ) / 180.0F )

typedef float vec_t;
typedef vec_t vec3_t[3];

#define DotProduct(x,y)			((x)[0]*(y)[0]+(x)[1]*(y)[1]+(x)[2]*(y)[2])
#define VectorSubtract(a,b,c)	((c)[0]=(a)[0]-(b)[0],(c)[1]=(a)[1]-(b)[1],(c)[2]=(a)[2]-(b)[2])
#define VectorAdd(a,b,c)		((c)[0]=(a)[0]+(b)[0],(c)[1]=(a)[1]+(b)[1],(c)[2]=(a)[2]+(b)[2])
#define VectorCopy(a,b)			((b)[0]=(a)[0],(b)[1]=(a)[1],(b)[2]=(a)[2])
#define	VectorScale(v,s,o)	((o)[0]=(v)[0]*(s),(o)[1]=(v)[1]*(s),(o)[2]=(v)[2]*(s))
#define	VectorMA(v,s,b,o)	((o)[0]=(v)[0]+(b)[0]*(s),(o)[1]=(v)[1]+(b)[1]*(s),(o)[2]=(v)[2]+(b)[2]*(s))

void PerpendicularVector( vec3_t dst, const vec3_t src );
void ProjectPointOnPlane( vec3_t dst, const vec3_t p, const vec3_t normal );
void MatrixMultiply(vec_t in1[3][3], vec_t in2[3][3], vec_t out[3][3]);
vec_t VectorNormalize( vec3_t v );
vec_t VectorNormalize2( const vec3_t v, vec3_t out);
void CrossProduct( const vec3_t v1, const vec3_t v2, vec3_t cross );

void CrossProduct( const vec3_t v1, const vec3_t v2, vec3_t cross ) {
	cross[0] = v1[1]*v2[2] - v1[2]*v2[1];
	cross[1] = v1[2]*v2[0] - v1[0]*v2[2];
	cross[2] = v1[0]*v2[1] - v1[1]*v2[0];
}

vec_t VectorNormalize2( const vec3_t v, vec3_t out) {
	vec_t	length, ilength;

	length = v[0]*v[0] + v[1]*v[1] + v[2]*v[2];
	length = sqrt (length);

	if (length)
	{
		ilength = 1/length;
		out[0] = v[0]*ilength;
		out[1] = v[1]*ilength;
		out[2] = v[2]*ilength;
	} else {
		out[0] = 0;
		out[1] = 0;
		out[2] = 0;
	}
		
	return length;

}

vec_t VectorNormalize( vec3_t v ) {
	// NOTE: TTimo - Apple G4 altivec source uses double?
	vec_t	length, ilength;

	length = v[0]*v[0] + v[1]*v[1] + v[2]*v[2];
	length = sqrt (length);

	if ( length ) {
		ilength = 1/length;
		v[0] *= ilength;
		v[1] *= ilength;
		v[2] *= ilength;
	}
		
	return length;
}

void MatrixMultiply(vec_t in1[3][3], vec_t in2[3][3], vec_t out[3][3]) {
	out[0][0] = in1[0][0] * in2[0][0] + in1[0][1] * in2[1][0] +
				in1[0][2] * in2[2][0];
	out[0][1] = in1[0][0] * in2[0][1] + in1[0][1] * in2[1][1] +
				in1[0][2] * in2[2][1];
	out[0][2] = in1[0][0] * in2[0][2] + in1[0][1] * in2[1][2] +
				in1[0][2] * in2[2][2];
	out[1][0] = in1[1][0] * in2[0][0] + in1[1][1] * in2[1][0] +
				in1[1][2] * in2[2][0];
	out[1][1] = in1[1][0] * in2[0][1] + in1[1][1] * in2[1][1] +
				in1[1][2] * in2[2][1];
	out[1][2] = in1[1][0] * in2[0][2] + in1[1][1] * in2[1][2] +
				in1[1][2] * in2[2][2];
	out[2][0] = in1[2][0] * in2[0][0] + in1[2][1] * in2[1][0] +
				in1[2][2] * in2[2][0];
	out[2][1] = in1[2][0] * in2[0][1] + in1[2][1] * in2[1][1] +
				in1[2][2] * in2[2][1];
	out[2][2] = in1[2][0] * in2[0][2] + in1[2][1] * in2[1][2] +
				in1[2][2] * in2[2][2];
}

void ProjectPointOnPlane( vec3_t dst, const vec3_t p, const vec3_t normal )
{
	vec_t d;
	vec3_t n;
	vec_t inv_denom;

	inv_denom =  DotProduct( normal, normal );
	inv_denom = 1.0f / inv_denom;

	d = DotProduct( normal, p ) * inv_denom;

	n[0] = normal[0] * inv_denom;
	n[1] = normal[1] * inv_denom;
	n[2] = normal[2] * inv_denom;

	dst[0] = p[0] - d * n[0];
	dst[1] = p[1] - d * n[1];
	dst[2] = p[2] - d * n[2];
}

void PerpendicularVector( vec3_t dst, const vec3_t src )
{
	int	pos;
	int i;
	vec_t minelem = 1.0F;
	vec3_t tempvec;

	/*
	** find the smallest magnitude axially aligned vector
	*/
	for ( pos = 0, i = 0; i < 3; i++ )
	{
		if ( fabs( src[i] ) < minelem )
		{
			pos = i;
			minelem = fabs( src[i] );
		}
	}
	tempvec[0] = tempvec[1] = tempvec[2] = 0.0F;
	tempvec[pos] = 1.0F;

	/*
	** project the point onto the plane defined by src
	*/
	ProjectPointOnPlane( dst, tempvec, src );

	/*
	** normalize the result
	*/
	VectorNormalize( dst );
}

/***************\
* THE FUNCTIONS *
\***************/

void RPAV_QUAKE3( vec3_t dst, const vec3_t dir, const vec3_t point,
							 vec_t degrees ) {
	vec_t	m[3][3];
	vec_t	im[3][3];
	vec_t	zrot[3][3];
	vec_t	tmpmat[3][3];
	vec_t	rot[3][3];
	int	i;
	vec3_t vr, vup, vf;
	vec_t	rad;

	vf[0] = dir[0];
	vf[1] = dir[1];
	vf[2] = dir[2];

	PerpendicularVector( vr, dir );
	CrossProduct( vr, vf, vup );

	m[0][0] = vr[0];
	m[1][0] = vr[1];
	m[2][0] = vr[2];

	m[0][1] = vup[0];
	m[1][1] = vup[1];
	m[2][1] = vup[2];

	m[0][2] = vf[0];
	m[1][2] = vf[1];
	m[2][2] = vf[2];

	memcpy( im, m, sizeof( im ) );

	im[0][1] = m[1][0];
	im[0][2] = m[2][0];
	im[1][0] = m[0][1];
	im[1][2] = m[2][1];
	im[2][0] = m[0][2];
	im[2][1] = m[1][2];

	memset( zrot, 0, sizeof( zrot ) );
	zrot[0][0] = zrot[1][1] = zrot[2][2] = 1.0F;

	rad = DEG2RAD( degrees );
	zrot[0][0] = cos( rad );
	zrot[0][1] = sin( rad );
	zrot[1][0] = -sin( rad );
	zrot[1][1] = cos( rad );

	MatrixMultiply( m, zrot, tmpmat );
	MatrixMultiply( tmpmat, im, rot );

	for ( i = 0; i < 3; i++ ) {
		dst[i] = rot[i][0] * point[0] + rot[i][1] * point[1] + rot[i][2] * point[2];
	}
}

void RPAV_TREMULOUS( vec3_t dst, const vec3_t dir, const vec3_t point,
							 vec_t degrees ) {
	vec_t sin_a;
	vec_t cos_a;
	vec_t cos_ia;
	vec_t i_i_ia;
	vec_t j_j_ia;
	vec_t k_k_ia;
	vec_t i_j_ia;
	vec_t i_k_ia;
	vec_t j_k_ia;
	vec_t a_sin;
	vec_t b_sin;
	vec_t c_sin;
	vec_t rot[3][3];

	cos_ia = DEG2RAD(degrees);
	sin_a = sin(cos_ia);
	cos_a = cos(cos_ia);
	cos_ia = 1.0F - cos_a;

	i_i_ia = dir[0] * dir[0] * cos_ia;
	j_j_ia = dir[1] * dir[1] * cos_ia;
	k_k_ia = dir[2] * dir[2] * cos_ia;
	i_j_ia = dir[0] * dir[1] * cos_ia;
	i_k_ia = dir[0] * dir[2] * cos_ia;
	j_k_ia = dir[1] * dir[2] * cos_ia;

	a_sin = dir[0] * sin_a;
	b_sin = dir[1] * sin_a;
	c_sin = dir[2] * sin_a;

	rot[0][0] = i_i_ia + cos_a;
	rot[0][1] = i_j_ia - c_sin;
	rot[0][2] = i_k_ia + b_sin;
	rot[1][0] = i_j_ia + c_sin;
	rot[1][1] = j_j_ia + cos_a;
	rot[1][2] = j_k_ia - a_sin;
	rot[2][0] = i_k_ia - b_sin;
	rot[2][1] = j_k_ia + a_sin;
	rot[2][2] = k_k_ia + cos_a;

	dst[0] = point[0] * rot[0][0] + point[1] * rot[0][1] + point[2] * rot[0][2];
	dst[1] = point[0] * rot[1][0] + point[1] * rot[1][1] + point[2] * rot[1][2];
	dst[2] = point[0] * rot[2][0] + point[1] * rot[2][1] + point[2] * rot[2][2];
}

void RPAV_NEW( vec3_t dst, const vec3_t dir,
                              const vec3_t point, vec_t degrees ) {
	vec_t sind, cosd, expr;
	vec3_t dxp;

	degrees = DEG2RAD( degrees );
	sind = sin( degrees );
	cosd = cos( degrees );
	expr = ( 1 - cosd ) * DotProduct( dir, point );
	CrossProduct( dir, point, dxp );

	dst[0] = expr*dir[0] + cosd*point[0] + sind*dxp[0];
	dst[1] = expr*dir[1] + cosd*point[1] + sind*dxp[1];
	dst[2] = expr*dir[2] + cosd*point[2] + sind*dxp[2];
}

/**************\
* TESTING CODE *
\**************/

#define DATA_COUNT 999
#define REPEAT_COUNT 99999

vec3_t* dirs;
vec3_t* points;
vec_t* degs;
vec3_t* work;

void fillup() {
	int n;
	dirs = malloc( sizeof( vec3_t[ DATA_COUNT ] ) );
	points = malloc( sizeof( vec3_t[ DATA_COUNT ] ) );
	degs = malloc( sizeof( vec_t[ DATA_COUNT ] ) );
	work = malloc( sizeof( vec3_t[ DATA_COUNT ] ) );

	for( n = 0; n < DATA_COUNT; n++ ) {
		dirs[n][0] = (vec_t)rand();
		dirs[n][1] = (vec_t)rand();
		dirs[n][2] = (vec_t)rand();
		VectorNormalize( dirs[n] );

		points[n][0] = (vec_t)rand();
		points[n][1] = (vec_t)rand();
		points[n][2] = (vec_t)rand();

		degs[n] = (vec_t)rand();
	}
}

void test( void (*RPAV)( vec3_t, const vec3_t, const vec3_t, vec_t ), char* name, vec3_t final ) {
	int n, k;
	clock_t c1, c2;

   	for( n = 0; n < DATA_COUNT; n++ ) {
		VectorCopy( points[n], work[n] );
	}

	c1 = clock();
	for( k = 0; k < REPEAT_COUNT; k++ ) {
		for( n = 1; n < DATA_COUNT; n++ ) {
			(*RPAV)( work[n], dirs[n], work[n-1], degs[n] );
		}
		VectorCopy( work[ DATA_COUNT - 1 ], work[0] );
	}
	c2 = clock();

	printf( "%s: %imsec\n", name, c2 - c1 );

	VectorCopy( work[0], final );
}

int main() {
	int n;
	vec3_t final[3];

	fillup();

	for( n = 0; n < 6; n++ ) {
		vec3_t dst;

		RPAV_QUAKE3( dst, dirs[n], points[n], degs[n] );
		printf( "RPAV_QUAKE3   : %f, %f, %f\n", dst[0], dst[1], dst[2] );

		RPAV_TREMULOUS( dst, dirs[n], points[n], degs[n] );
		printf( "RPAV_TREMULOUS: %f, %f, %f\n", dst[0], dst[1], dst[2] );

		RPAV_NEW( dst, dirs[n], points[n], degs[n] );
		printf( "RPAV_NEW      : %f, %f, %f\n", dst[0], dst[1], dst[2] );
		
		printf( "\n" );
	}

	printf( "\nSPEED TEST (this may take a few minutes)\n\n" );

	test( RPAV_QUAKE3, "RPAV_QUAKE3", final[0] );
	test( RPAV_TREMULOUS, "RPAV_TREMULOUS", final[1] );
	test( RPAV_NEW, "RPAV_NEW", final[2] );

	printf( "\nFINAL DATA AFTER %i SEQUENTIAL ITERATIONS (LOL):\n", DATA_COUNT * REPEAT_COUNT );
	printf( "RPAV_QUAKE3   : %f, %f, %f\n", final[0][0], final[0][1], final[0][2] );
	printf( "RPAV_TREMULOUS: %f, %f, %f\n", final[1][0], final[1][1], final[1][2] );
	printf( "RPAV_NEW      : %f, %f, %f\n", final[2][0], final[2][1], final[2][2] );

	return 0;
}