BOOL hit_geo_sphere (GEO *Generic, RAY *Ray, HIT *Hit, PAIR *Bound, void *Info)
{
GEO_SPHERE *Geo;
VECTOR Point;
REAL a, b, Distance, Delta;
Geo = (GEO_SPHERE *) Generic;
VEC_SUB (Point, Ray->Point, Geo->Point);
a = - VEC_DOT (Point, Ray->Vector);
b = VEC_DOT (Point, Point);
Delta = a * a - b + Geo->Radius * Geo->Radius;
if (Delta < 0.0)
return (FALSE);
Delta = sqrt (Delta);
Distance = a - Delta; /* - Epsilon;*/
if (Distance < Bound->u || Distance > Bound->v)
return (FALSE);
if (Hit) {
Ray->Distance = Distance;
VEC_LIN (Point, Ray->Point, Distance, Ray->Vector);
VEC_SUB (Hit->Normal, Point, Geo->Point);
if (VEC_DOT (Ray->Vector, Hit->Normal) > 0.0)
VEC_NEG (Hit->Normal);
VEC_UNIT (Hit->Normal, Distance);
VEC_LIN (Hit->Point, Point, Epsilon, Hit->Normal);
xyz2uv_geo_sphere (Geo, Hit);
}
return (TRUE);
}
/********************************************************
* Search for an intersection between a nappe and a ray *
*******************************************************/
BOOL hit_geo_nappe (GEO *Generic, RAY *Ray, HIT *Hit, PAIR *Bound, void *Info)
{
GEO_NAPPE *Geo;
FCT *Fct;
PNT *Pnt, *PntA, *PntB;
VECTOR Normal;
VECTOR Point;
REAL a, b, c, u, v, uA, vA, uB, vB, Distance, Real;
Geo = (GEO_NAPPE *) Generic;
Fct = (FCT *) Info;
Distance = VEC_DOT (Ray->Vector, Fct->Normal);
if (ABS(Distance) < EPSILON)
return (FALSE);
Pnt = Geo->TabPnt + Fct->i;
VEC_SUB (Point, Pnt->Point, Ray->Point);
Distance = VEC_DOT (Point, Fct->Normal) / Distance ; /*-Epsilon est vire*/
if (Distance < Bound->u || Distance > Bound->v)
return (FALSE);
VEC_LIN (Point, Ray->Point, Distance, Ray->Vector);
if ((ABS(Fct->Normal.z) > ABS(Fct->Normal.x)) && (ABS(Fct->Normal.z) > ABS(Fct->Normal.y))) {
u = Point.x - Pnt->Point.x; v = Point.y - Pnt->Point.y;
PntA = Geo->TabPnt + Fct->j; PntB = Geo->TabPnt + Fct->k;
uA = PntA->Point.x - Pnt->Point.x; vA = PntA->Point.y - Pnt->Point.y;
uB = PntB->Point.x - Pnt->Point.x; vB = PntB->Point.y - Pnt->Point.y;
a = uA*vB - vA*uB; b = (u*vB - v*uB)/a; c = (v*uA-u*vA) / a; a = 1.0-b-c;
if (a > -EPSILON && b > -EPSILON && c > -EPSILON) {
VEC_INTER (Normal, a, Pnt->Normal, b, PntA->Normal, c, PntB->Normal);
Real = VEC_DOT (Ray->Vector, Normal);
if (Real > 0.0)
return (FALSE);
if (Hit) {
Real = VEC_LEN (Normal); VEC_UNIT (Normal, Real);
Ray->Distance = Distance; Hit->Point = Point; Hit->Normal = Normal;
xyz2uv_geo_nappe (Geo, Hit, Fct);
}
return (TRUE);
}
if (Fct->l == Fct->i)
return (FALSE);
PntA = Geo->TabPnt + Fct->l;
uA = PntA->Point.x - Pnt->Point.x; vA = PntA->Point.y - Pnt->Point.y;
a = uA*vB - vA*uB; b = (u*vB - v*uB)/a; c = (v*uA - u*vA)/a; a = 1.0-b-c;
if (a > -EPSILON && b > -EPSILON && c > -EPSILON) {
VEC_INTER (Normal, a, Pnt->Normal, b, PntA->Normal, c, PntB->Normal);
Real = VEC_DOT (Ray->Vector, Normal);
if (Real > 0.0)
return (FALSE);
if (Hit) {
Real = VEC_LEN (Normal); VEC_UNIT (Normal, Real);
Ray->Distance = Distance; Hit->Point = Point; Hit->Normal = Normal;
xyz2uv_geo_nappe (Geo, Hit, Fct);
}
return (TRUE);
}
return (FALSE);
}
else if (ABS(Fct->Normal.y) > ABS(Fct->Normal.x)) {
u = Point.z - Pnt->Point.z; v = Point.x - Pnt->Point.x;
PntA = Geo->TabPnt + Fct->j; PntB = Geo->TabPnt + Fct->k;
uA = PntA->Point.z - Pnt->Point.z; vA = PntA->Point.x - Pnt->Point.x;
uB = PntB->Point.z - Pnt->Point.z; vB = PntB->Point.x - Pnt->Point.x;
a = uA*vB - vA*uB; b = (u*vB - v*uB)/a; c = (v*uA - u*vA)/a; a = 1.0-b-c;
if (a > -EPSILON && b > -EPSILON && c > -EPSILON) {
VEC_INTER (Normal, a, Pnt->Normal, b, PntA->Normal, c, PntB->Normal);
Real = VEC_DOT (Ray->Vector, Normal);
if (Real > 0.0)
return (FALSE);
if (Hit) {
Real = VEC_LEN (Normal); VEC_UNIT (Normal, Real);
Ray->Distance = Distance; Hit->Point = Point; Hit->Normal = Normal;
xyz2uv_geo_nappe (Geo, Hit, Fct);
}
return (TRUE);
}
if (Fct->l == Fct->i) return (FALSE);
PntA = Geo->TabPnt + Fct->l;
uA = PntA->Point.z - Pnt->Point.z; vA = PntA->Point.x - Pnt->Point.x;
a = uA*vB - vA*uB; b = (u*vB - v*uB)/a; c = (v*uA - u*vA)/a; a = 1.0-b-c;
if (a > -EPSILON && b > -EPSILON && c > -EPSILON) {
VEC_INTER (Normal, a, Pnt->Normal, b, PntA->Normal, c, PntB->Normal);
Real = VEC_DOT (Ray->Vector, Normal);
if (Real > 0.0)
return (FALSE);
if (Hit) {
Real = VEC_LEN (Normal); VEC_UNIT (Normal, Real);
Ray->Distance = Distance; Hit->Point = Point; Hit->Normal = Normal;
xyz2uv_geo_nappe (Geo, Hit, Fct);
}
return (TRUE);
}
return (FALSE);
}
else if (ABS(Fct->Normal.x) > EPSILON) {
u = Point.y - Pnt->Point.y; v = Point.z - Pnt->Point.z;
PntA = Geo->TabPnt + Fct->j; PntB = Geo->TabPnt + Fct->k;
uA = PntA->Point.y - Pnt->Point.y; vA = PntA->Point.z - Pnt->Point.z;
uB = PntB->Point.y - Pnt->Point.y; vB = PntB->Point.z - Pnt->Point.z;
a = uA*vB - vA*uB; b = (u*vB - v*uB)/a; c = (v*uA - u*vA)/a; a = 1.0-b-c;
if (a > -EPSILON && b > -EPSILON && c > -EPSILON) {
VEC_INTER (Normal, a, Pnt->Normal, b, PntA->Normal, c, PntB->Normal);
Real = VEC_DOT (Ray->Vector, Normal);
if (Real > 0.0)
return (FALSE);
if (Hit) {
Real = VEC_LEN (Normal); VEC_UNIT (Normal, Real);
Ray->Distance = Distance; Hit->Point = Point; Hit->Normal = Normal;
xyz2uv_geo_nappe (Geo, Hit, Fct);
}
return (TRUE);
}
if (Fct->l == Fct->i) return (FALSE);
PntA = Geo->TabPnt + Fct->l;
uA = PntA->Point.y - Pnt->Point.y; vA = PntA->Point.z - Pnt->Point.z;
a = uA*vB - vA*uB; b = (u*vB - v*uB)/a; c = (v*uA - u*vA)/a; a = 1.0-b-c;
if (a > -EPSILON && b > -EPSILON && c > -EPSILON) {
VEC_INTER (Normal, a, Pnt->Normal, b, PntA->Normal, c, PntB->Normal);
Real = VEC_DOT (Ray->Vector, Normal);
if (Real > 0.0)
return (FALSE);
if (Hit) {
Real = VEC_LEN (Normal); VEC_UNIT (Normal, Real);
Ray->Distance = Distance; Hit->Point = Point; Hit->Normal = Normal;
xyz2uv_geo_nappe (Geo, Hit, Fct);
}
return (TRUE);
}
return (FALSE);
}
return (FALSE);
}
