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#include "base/nebu_vector.h"
#include <math.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
vec4* vec4Add(vec4 *pOut, const vec4 *pV1, const vec4 *pV2) {
pOut->v[0] = pV1->v[0] + pV2->v[0];
pOut->v[1] = pV1->v[1] + pV2->v[1];
pOut->v[2] = pV1->v[2] + pV2->v[2];
pOut->v[3] = pV1->v[3] + pV2->v[3];
return pOut;
}
vec4* vec4Sub(vec4 *pOut, const vec4 *pV1, const vec4 *pV2) {
pOut->v[0] = pV1->v[0] - pV2->v[0];
pOut->v[1] = pV1->v[1] - pV2->v[1];
pOut->v[2] = pV1->v[2] - pV2->v[2];
pOut->v[3] = pV1->v[3] - pV2->v[3];
return pOut;
}
vec3* vec3Add(vec3 *pOut, const vec3 *pV1, const vec3 *pV2) {
pOut->v[0] = pV1->v[0] + pV2->v[0];
pOut->v[1] = pV1->v[1] + pV2->v[1];
pOut->v[2] = pV1->v[2] + pV2->v[2];
return pOut;
}
vec3* vec3Sub(vec3 *pOut, const vec3 *pV1, const vec3 *pV2) {
pOut->v[0] = pV1->v[0] - pV2->v[0];
pOut->v[1] = pV1->v[1] - pV2->v[1];
pOut->v[2] = pV1->v[2] - pV2->v[2];
return pOut;
}
vec3* vec3Cross(vec3 *pOut, const vec3 *pV1, const vec3 *pV2) {
vec3 tmp;
tmp.v[0] = pV1->v[1] * pV2->v[2] - pV1->v[2] * pV2->v[1];
tmp.v[1] = pV1->v[2] * pV2->v[0] - pV1->v[0] * pV2->v[2];
tmp.v[2] = pV1->v[0] * pV2->v[1] - pV1->v[1] * pV2->v[0];
memcpy(pOut, &tmp, sizeof(vec3));
return pOut;
}
float vec3Dot(const vec3 *pV1, const vec3 *pV2) {
return pV1->v[0] * pV2->v[0] +
pV1->v[1] * pV2->v[1] + pV1->v[2] * pV2->v[2];
}
float vec4Dot(const vec4 *pV1, const vec4 *pV2) {
return
pV1->v[0] * pV2->v[0] + pV1->v[1] * pV2->v[1] +
pV1->v[2] * pV2->v[2] + pV1->v[3] * pV2->v[3];
}
float vec3Length(const vec3 *pV) {
return (float) sqrt( pV->v[0] * pV->v[0] +
pV->v[1] * pV->v[1] + pV->v[2] * pV->v[2] );
}
float vec3LengthSqr(const vec3 *pV) {
return pV->v[0] * pV->v[0] +
pV->v[1] * pV->v[1] + pV->v[2] * pV->v[2];
}
vec3* vec3Normalize(vec3 *pOut, const vec3 *pV) {
float fLength = vec3Length(pV);
if(fLength != 0) {
pOut->v[0] = pV->v[0] / fLength;
pOut->v[1] = pV->v[1] / fLength;
pOut->v[2] = pV->v[2] / fLength;
}
return pOut;
}
void vec4Print(const vec4 *v) {
int i;
printf("[ ");
for(i = 0; i < 4; i++) {
printf("%.3f ", v->v[i]);
}
printf(" ]\n");
}
void vec3Print(const vec3 *v) {
int i;
printf("[ ");
for(i = 0; i < 3; i++) {
printf("%.3f ", v->v[i]);
}
printf(" ]\n");
}
vec4* vec4fromVec3(vec4 *pOut, const vec3 *pV) {
memcpy(pOut, pV, sizeof(vec3));
pOut->v[3] = 1;
return pOut;
}
vec3* vec3fromVec4(vec3 *pOut, const vec4 *pV) {
if(pV->v[3] != 0) {
pOut->v[0] = pV->v[0] / pV->v[3];
pOut->v[1] = pV->v[1] / pV->v[3];
pOut->v[2] = pV->v[2] / pV->v[3];
return pOut;
} else {
memset(pOut, 0, sizeof(vec3));
return NULL;
}
}
vec3* vec3Copy(vec3 *pOut, const vec3 *pV) {
memcpy(pOut, pV, sizeof(vec3));
return pOut;
}
vec3* vec3Scale(vec3 *pOut, const vec3 *pV, float f) {
pOut->v[0] = f * pV->v[0];
pOut->v[1] = f * pV->v[1];
pOut->v[2] = f * pV->v[2];
return pOut;
}
unsigned int uintFromVec3(vec3 *pV) {
return
( ( (unsigned int)(pV->v[0] * 127.0f + 128.0f) ) << 16 ) +
( ( (unsigned int)(pV->v[1] * 127.0f + 128.0f) ) << 8 ) +
( ( (unsigned int)(pV->v[2] * 127.0f + 128.0f) ) << 0 );
}
vec3* vec3Zero(vec3 *pV) {
memset(pV, 0, sizeof(vec3));
return pV;
}
vec3* vec3TriNormalDirection(vec3* pOut,
const vec3* pV1,
const vec3* pV2,
const vec3 *pV3) {
vec3 v1, v2;
vec3Sub(&v1, pV2, pV1);
vec3Sub(&v2, pV3, pV1);
vec3Cross(pOut, &v1, &v2);
return pOut;
}
vec2* vec2Copy(vec2 *pOut, const vec2 *pV) {
memcpy(pOut, pV, sizeof(vec2));
return pOut;
}
vec2* vec2_Orthogonal(vec2 *pOut, const vec2 *pV) {
pOut->v[0] = pV->v[1];
pOut->v[1] = - pV->v[0];
return pOut;
}
vec2* vec2Add(vec2 *pOut, const vec2 *pV1, const vec2 *pV2) {
pOut->v[0] = pV1->v[0] + pV2->v[0];
pOut->v[1] = pV1->v[1] + pV2->v[1];
return pOut;
}
vec2* vec2Sub(vec2 *pOut, const vec2 *pV1, const vec2 *pV2) {
pOut->v[0] = pV1->v[0] - pV2->v[0];
pOut->v[1] = pV1->v[1] - pV2->v[1];
return pOut;
}
vec2* vec2Scale(vec2 *pOut, const vec2 *pV, float fScale) {
pOut->v[0] = pV->v[0] * fScale;
pOut->v[1] = pV->v[1] * fScale;
return pOut;
}
vec2* vec2Normalize(vec2 *pOut, const vec2 *pV) {
return vec2Scale(pOut, pV, 1 / vec2Length(pV));
}
float vec2Dot(const vec2 *pV1, const vec2 *pV2) {
return pV1->v[0] * pV2->v[0] + pV1->v[1] * pV2->v[1];
}
float vec2Length(const vec2 *pV) {
float fLength2 = (pV->v[0] * pV->v[0] + pV->v[1] * pV->v[1]);
float l = sqrt(fLength2);
return l;
}
int segment2_findT(float *t, const segment2 *s, const vec2 *v) {
float epsilon = 0.001;
if( fabs(s->vDirection.v[0]) > fabs(s->vDirection.v[1]) ) {
*t = (v->v[0] - s->vStart.v[0]) / s->vDirection.v[0];
if( fabs(v->v[1] - (s->vStart.v[1] + *t * s->vDirection.v[1])) >
epsilon ) {
return 1;
}
} else {
*t = (v->v[1] - s->vStart.v[1]) / s->vDirection.v[1];
if( fabs(v->v[0] - (s->vStart.v[0] + *t * s->vDirection.v[0])) >
epsilon ) {
return 1;
}
}
return 0;
}
vec2* segment2_IntersectParallel(vec2 *pOut, float *t1, float *t2,
const segment2 *s1, const segment2 *s2) {
// if the lines don't overlap, return NULL
// else find t2 for t1 == 0
// if t2 in [0,1] return t2, t1 = 0
// else find t1 for t2 == 0 and t2 == 1
// if t1 < 0 return NULL (no intersection)
// else return the smaller t1 and the corresponding t2
vec2 v; float t;
// if the lines don't overlap, return NULL
// else find t2 for t1 == 0
vec2Copy(&v, &s1->vStart);
if(segment2_findT(t2, s2, &v)) {
// printf("[vector] are not collinear\n");
return NULL;
}
// if t2 in [0,1] return t2, t1 = 0
if(*t2 >= 0 && *t2 <= 1) {
vec2Copy(pOut, &s1->vStart);
*t1 = 0;
return pOut;
}
// else find t1 for t2 == 0 and t2 == 1
vec2Copy(&v, &s2->vStart);
if(segment2_findT(t1, s1, &v))
return NULL;
// if t1 < 0 return NULL (no intersection)
if(*t1 < 0) return NULL;
vec2Add(&v, &s2->vStart, &s2->vDirection);
if(segment2_findT(&t, s1, &v))
return NULL;
assert(t >= 0);
if(*t1 > 1 && t > 1)
return NULL;
// else return the smaller t1 and the corresponding t2
if(t < *t1) {
*t1 = t;
*t2 = 1;
vec2Copy(pOut, &v);
} else {
*t2 = 0;
vec2Copy(pOut, &s2->vStart);
}
return pOut;
}
vec2* segment2_IntersectNonParallel(vec2 *pOut, float *t1, float *t2,
const segment2 *s1, const segment2 *s2) {
vec3 v1, v2;
vec3 tmp1, tmp2;
vec3 vIntersection;
// compute the homogenous line coordinates
tmp1.v[0] = s1->vStart.v[0];
tmp1.v[1] = s1->vStart.v[1];
tmp1.v[2] = 1;
tmp2.v[0] = s1->vStart.v[0] + s1->vDirection.v[0];
tmp2.v[1] = s1->vStart.v[1] + s1->vDirection.v[1];
tmp2.v[2] = 1;
vec3Cross(&v1, &tmp1, &tmp2);
tmp1.v[0] = s2->vStart.v[0];
tmp1.v[1] = s2->vStart.v[1];
tmp1.v[2] = 1;
tmp2.v[0] = s2->vStart.v[0] + s2->vDirection.v[0];
tmp2.v[1] = s2->vStart.v[1] + s2->vDirection.v[1];
tmp2.v[2] = 1;
vec3Cross(&v2, &tmp1, &tmp2);
// compute the intersection in homogenous coordinates and
// project back to 2d
vec3Cross(&vIntersection, &v1, &v2);
pOut->v[0] = vIntersection.v[0] / vIntersection.v[2];
pOut->v[1] = vIntersection.v[1] / vIntersection.v[2];
// compute t1, t2
if(fabs(s1->vDirection.v[0]) > fabs(s1->vDirection.v[1]))
*t1 = (pOut->v[0] - s1->vStart.v[0]) / s1->vDirection.v[0];
else
*t1 = (pOut->v[1] - s1->vStart.v[1]) / s1->vDirection.v[1];
if(fabs(s2->vDirection.v[0]) > fabs(s2->vDirection.v[1]))
*t2 = (pOut->v[0] - s2->vStart.v[0]) / s2->vDirection.v[0];
else
*t2 = (pOut->v[1] - s2->vStart.v[1]) / s2->vDirection.v[1];
return pOut;
}
vec2* segment2_Intersect(vec2 *pOut, float *t1, float *t2,
const segment2 *s1, const segment2 *s2) {
// check if s1, s2 are parallel
vec2 tmp;
if( fabs(vec2Dot(&s1->vDirection,
vec2_Orthogonal(&tmp, & s2->vDirection) )) < 0.1) {
// printf("[vector] lines are parallel\n");
pOut = segment2_IntersectParallel(pOut, t1, t2, s1, s2);
if(!pOut) {
*t1 = 0;
*t2 = 0;
}
} else {
pOut = segment2_IntersectNonParallel(pOut, t1, t2, s1, s2);
}
return pOut;
}
float segment2_Length(const segment2 *s) {
return vec2Length(&s->vDirection);
}
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