/*===========================================*/
int VF_BackFaceCullViewPoint(ViewPort *view, Poly *poly_j)
{
int n;
Vector *normal_i, *normal_j, r;
normal_i = &(view->view_normal);
normal_j = &(poly_j->normal);
for (n=0; n<poly_j->np; n++) {
V3_Sub(&(poly_j->p[n]), &(view->view_point), &r);
if ((V3_Dot(&r, normal_i)>0.0) && (-V3_Dot(&r, normal_j)>0.0)) return 0;
}
return 1;
}
/*====================================*/
int VF_RayIntersect(Ray *ray, double tmax, Poly *poly)
{
double t, n_dot_d;
Vector q;
n_dot_d = V3_Dot(&(poly->normal), &ray->D);
if (fabs(n_dot_d)<VF_RAY_TEST) return 0;
V3_Sub(&(poly->p[0]), &ray->O, &q);
t = V3_Dot(&(poly->normal), &q)/n_dot_d;
if (t<=0.0 || t>=tmax) return 0;
if (poly->np!=2) {
return (VF_InsidePoly(ray, t, poly));
} else {
return (VF_InsideLine(ray, t, poly));
}
}
/*===========================================*/
int VF_BackFaceCullPolys(Poly *poly_i, Poly *poly_j)
{
int n, m;
double tmp;
Vector *normal_i, *normal_j, r;
normal_i = &(poly_i->normal);
normal_j = &(poly_j->normal);
for (m=0; m<poly_i->np; m++) {
for (n=0; n<poly_j->np; n++) {
V3_Sub(&(poly_j->p[n]), &(poly_i->p[m]), &r);
V3_Normalize(&r,tmp);
if ((V3_Dot(&r, normal_i)>0.0) && (-V3_Dot(&r, normal_j)>0.0)) return 0;
}
}
return 1;
}
/*=========================================*/
int VF_BehindPlane(Plane *plane, Poly *poly)
{
int n;
double value, spatial_tol;
VFtopology *topology=VF_CurrentTopology();
spatial_tol = topology->spatial_tol;
for (n=0; n<poly->np; n++) {
value = V3_Dot(&(poly->p[n]), &(plane->normal)) + plane->d;
if (value > spatial_tol) return 0;
}
return 1;
}
/*=========================================*/
int VF_BehindViewPoint(ViewPort *view, Poly *poly)
{
int n;
double value, spatial_tol;
VFtopology *topology=VF_CurrentTopology();
spatial_tol = topology->spatial_tol;
for (n=0; n<poly->np; n++) {
value = V3_Dot(&(poly->p[n]), &(view->view_normal)) + view->d;
if (value > spatial_tol) return 0;
}
return 1;
}
/*=========================================*/
int VF_BehindAndBackFaceCullViewPoint(ViewPort *view, Poly *poly)
{
int n;
double value, spatial_tol;
Vector *normal_i, *normal_j, r;
VFtopology *topology=VF_CurrentTopology();
spatial_tol = topology->spatial_tol;
for (n=0; n<poly->np; n++) {
value = V3_Dot(&(poly->p[n]), &(view->view_normal)) + view->d;
if (value > spatial_tol) {
/*===========================================*/
/* THIS VERTEX IS IN FRONT OF THE VIEWPOINT, */
/* NOW CHECK IF IT IS ALSO FACING IT */
/*===========================================*/
normal_i = &(view->view_normal);
normal_j = &(poly->normal);
V3_Sub(&(poly->p[n]), &(view->view_point), &r);
if ((V3_Dot(&r, normal_i)>0.0) && (-V3_Dot(&r, normal_j)>0.0)) return 0;
break;
}
}
return 1;
}
static int
NearestConstraintAxis (HVect loose,
HVect *axes,
int nAxes)
{
HVect onPlane;
register double max, dot;
register int i, nearest;
max = -1; nearest = 0;
for (i=0; i<nAxes; i++)
{
onPlane = ConstrainToAxis(loose, axes[i]);
dot = V3_Dot(onPlane, loose);
if (dot>max)
{
max = dot; nearest = i;
}
}
return (nearest);
}
static HVect
ConstrainToAxis (HVect loose,
HVect axis)
{
HVect onPlane;
register double norm;
onPlane = V3_Sub(loose, V3_Scale(axis, V3_Dot(axis, loose)));
norm = V3_Norm(onPlane);
if (norm > 0.0)
{
if (onPlane.z < 0.0) onPlane = V3_Negate(onPlane);
return ( V3_Scale(onPlane, 1/sqrt(norm)) );
}
/* else drop through */
/* ================= */
if (axis.z == 1) onPlane = V3_(1.0, 0.0, 0.0);
else onPlane = V3_Unit(V3_(-axis.y, axis.x, 0.0));
return (onPlane);
}
double VF_Visibility(Poly *poly_i, Poly *poly_j,
CandidateList *candidates, int nc)
{
int i, j, n, ns, cnt, nt, test_vertices=0;
double tmax, tmp, n_dot_d;
Ray ray0,*ray;
Point samples_i[4096], samples_j[4096];
Vector q;
Adaptive *adaptive;
VFenclosure *enclosure=VF_CurrentEnclosure();
adaptive = &(enclosure->adaptive);
if (nc==0) return(1.0);
VF_SamplesUVtoXYZ(poly_i, &(adaptive->visibility.sampling),
adaptive->visibility.sampleuv_i, samples_i);
VF_SamplesUVtoXYZ(poly_j, &(adaptive->visibility.sampling),
adaptive->visibility.sampleuv_j, samples_j);
ns = adaptive->visibility.sampling.n;
if (test_vertices) {
cnt = nt = ns+poly_i->np*poly_j->np;
} else {
cnt = nt = ns;
}
/*=================================================*/
/* TEST VISIBILITY OF RAYS BETWEEN SAMPLING POINTS */
/*=================================================*/
for (n=0; n<ns; n++) {
ray = &(adaptive->visibility.ray[n]);
ray->O = samples_i[n];
ray->vis = 0;
V3_Sub(&(samples_j[n]), &(ray->O), &(ray->D));
V3_Normalize(&(ray->D),tmp);
n_dot_d = V3_Dot(&(poly_j->normal), &(ray->D));
if (fabs(n_dot_d)<VF_RAY_TEST) {
cnt--;
} else {
V3_Sub(&(poly_j->p[0]), &(ray->O), &q);
tmax = V3_Dot(&(poly_j->normal), &q)/n_dot_d;
if (VF_RayPatchListTest(&(adaptive->visibility.ray[n]),
n, tmax, candidates, nc)) cnt--;
}
}
if (test_vertices) {
/*===============================================================*/
/* ALSO TEST RAYS BETWEEN ALL VERTEX COMBINATIONS FOR VISIBILITY */
/*===============================================================*/
for (i=0; i<poly_i->np; i++) {
for (j=0; j<poly_j->np; j++) {
ray0.vis = 0;
ray0.O = poly_i->p[i];
V3_Sub(&(poly_j->p[j]), &(ray0.O), &(ray0.D));
V3_Normalize(&(ray0.D),tmp);
n_dot_d = V3_Dot(&(poly_j->normal), &(ray0.D));
if (fabs(n_dot_d)<VF_RAY_TEST) {
cnt--;
} else {
V3_Sub(&(poly_j->p[0]), &(ray0.O), &q);
tmax = V3_Dot(&(poly_j->normal), &q)/n_dot_d;
if (VF_RayPatchListTest(&ray0, n, tmax, candidates, nc)) {
cnt--;
}
}
}
}
}
return ((double)(cnt)/(double)(nt));
}
void OBJECT::SortVertexEdges()
{
for (int x=0; x<VertexNum; x++)
{
if (VertexList[x].EdgeNum>2)
{
VECTOR3 vertvector;
VECTOR3 normal = V3_Normalize(VertexList[x].Normal);
VECTOR3 vx = VertexList[x].Position;
float *szogek = new float[VertexList[x].EdgeNum];
int e=GetEdgeVertex(this,x,VertexList[x].EdgeList[0]);
VECTOR3 refvector=VertexList[e].Position;
refvector = V3_Sub(refvector,vx);
VECTOR3 projvec=normal;
projvec=V3_Mults(projvec,V3_Dot(refvector,normal));
refvector = V3_Normalize(V3_Sub(refvector,projvec));
int y;
for (y=1; y<VertexList[x].EdgeNum; y++)
{
e=GetEdgeVertex(this,x,VertexList[x].EdgeList[y]);
vertvector = V3_Sub(VertexList[e].Position,vx);
projvec=V3_Mults(normal,V3_Dot(vertvector,normal));
vertvector = V3_Normalize(V3_Sub(vertvector,projvec));
float cosTheta = max(-1.0f,min(1.0f,V3_Dot(vertvector,refvector)));
float angle = (float)acos(cosTheta) * 180.0f / 3.1415f;
VECTOR3 crossProd=V3_Cross(vertvector,refvector);
if (V3_Dot(crossProd,normal) < 0) angle = 360 - angle;
szogek[y]=angle;
}
int smallest,b1;
float smallestvalue, b2;
for (int z=0; z<VertexList[x].EdgeNum; z++)
{
smallest=z;
smallestvalue=szogek[z];
for (y=z; y<VertexList[x].EdgeNum; y++)
{
if (szogek[y]<=smallestvalue)
{
smallest=y;
smallestvalue=szogek[y];
}
}
b2=szogek[smallest];
szogek[smallest]=szogek[z];
szogek[z]=b2;
b1=VertexList[x].EdgeList[smallest];
VertexList[x].EdgeList[smallest]=VertexList[x].EdgeList[z];
VertexList[x].EdgeList[z]=b1;
}
delete[] szogek;
}
}
}