static void calc_bbox(BBOX *BBox, BBOX_TREE **Finite, long first, long last)
{
long i;
DBL tmin, tmax;
VECTOR bmin, bmax;
BBOX *bbox;
Make_Vector(bmin, BOUND_HUGE, BOUND_HUGE, BOUND_HUGE);
Make_Vector(bmax, -BOUND_HUGE, -BOUND_HUGE, -BOUND_HUGE);
for (i = first; i < last; i++)
{
bbox = &(Finite[i]->BBox);
tmin = bbox->Lower_Left[X];
tmax = tmin + bbox->Lengths[X];
if (tmin < bmin[X]) { bmin[X] = tmin; }
if (tmax > bmax[X]) { bmax[X] = tmax; }
tmin = bbox->Lower_Left[Y];
tmax = tmin + bbox->Lengths[Y];
if (tmin < bmin[Y]) { bmin[Y] = tmin; }
if (tmax > bmax[Y]) { bmax[Y] = tmax; }
tmin = bbox->Lower_Left[Z];
tmax = tmin + bbox->Lengths[Z];
if (tmin < bmin[Z]) { bmin[Z] = tmin; }
if (tmax > bmax[Z]) { bmax[Z] = tmax; }
}
Make_BBox_from_min_max(*BBox, bmin, bmax);
}
void calc_bbox(BoundingBox *BBox, BBOX_TREE **Finite, ptrdiff_t first, ptrdiff_t last)
{
ptrdiff_t i;
DBL tmin, tmax;
Vector3d bmin, bmax;
BoundingBox *bbox;
bmin = Vector3d(BOUND_HUGE);
bmax = Vector3d(-BOUND_HUGE);
for(i = first; i < last; i++)
{
bbox = &(Finite[i]->BBox);
tmin = bbox->lowerLeft[X];
tmax = tmin + bbox->size[X];
if(tmin < bmin[X]) { bmin[X] = tmin; }
if(tmax > bmax[X]) { bmax[X] = tmax; }
tmin = bbox->lowerLeft[Y];
tmax = tmin + bbox->size[Y];
if(tmin < bmin[Y]) { bmin[Y] = tmin; }
if(tmax > bmax[Y]) { bmax[Y] = tmax; }
tmin = bbox->lowerLeft[Z];
tmax = tmin + bbox->size[Z];
if(tmin < bmin[Z]) { bmin[Z] = tmin; }
if(tmax > bmax[Z]) { bmax[Z] = tmax; }
}
Make_BBox_from_min_max(*BBox, bmin, bmax);
}
void Recompute_Inverse_BBox(BBOX *bbox, TRANSFORM *trans)
{
int i;
VECTOR lower_left, lengths, corner;
VECTOR mins, maxs;
if (trans == NULL)
{
return;
}
Assign_BBox_Vect(lower_left, bbox->Lower_Left);
Assign_BBox_Vect(lengths, bbox->Lengths);
Make_Vector(mins, BOUND_HUGE, BOUND_HUGE, BOUND_HUGE);
Make_Vector(maxs, -BOUND_HUGE, -BOUND_HUGE, -BOUND_HUGE);
for (i = 1; i <= 8; i++)
{
Assign_Vector(corner, lower_left);
corner[X] += ((i & 1) ? lengths[X] : 0.0);
corner[Y] += ((i & 2) ? lengths[Y] : 0.0);
corner[Z] += ((i & 4) ? lengths[Z] : 0.0);
MInvTransPoint(corner, corner, trans);
if (corner[X] < mins[X]) { mins[X] = corner[X]; }
if (corner[X] > maxs[X]) { maxs[X] = corner[X]; }
if (corner[Y] < mins[Y]) { mins[Y] = corner[Y]; }
if (corner[Y] > maxs[Y]) { maxs[Y] = corner[Y]; }
if (corner[Z] < mins[Z]) { mins[Z] = corner[Z]; }
if (corner[Z] > maxs[Z]) { maxs[Z] = corner[Z]; }
}
/* Clip bounding box at the largest allowed bounding box. */
if (mins[X] < -BOUND_HUGE / 2) { mins[X] = -BOUND_HUGE / 2; }
if (mins[Y] < -BOUND_HUGE / 2) { mins[Y] = -BOUND_HUGE / 2; }
if (mins[Z] < -BOUND_HUGE / 2) { mins[Z] = -BOUND_HUGE / 2; }
if (maxs[X] > BOUND_HUGE / 2) { maxs[X] = BOUND_HUGE / 2; }
if (maxs[Y] > BOUND_HUGE / 2) { maxs[Y] = BOUND_HUGE / 2; }
if (maxs[Z] > BOUND_HUGE / 2) { maxs[Z] = BOUND_HUGE / 2; }
Make_BBox_from_min_max(*bbox, mins, maxs);
}
static void Compute_Polygon_BBox(POLYGON *Polyg)
{
int i;
VECTOR p, Puv, Min, Max;
Min[X] = Min[Y] = Min[Z] = BOUND_HUGE;
Max[X] = Max[Y] = Max[Z] = -BOUND_HUGE;
for (i = 0; i < Polyg->Data->Number; i++)
{
Puv[X] = Polyg->Data->Points[i][X];
Puv[Y] = Polyg->Data->Points[i][Y];
Puv[Z] = 0.0;
MTransPoint(p, Puv, Polyg->Trans);
Min[X] = min(Min[X], p[X]);
Min[Y] = min(Min[Y], p[Y]);
Min[Z] = min(Min[Z], p[Z]);
Max[X] = max(Max[X], p[X]);
Max[Y] = max(Max[Y], p[Y]);
Max[Z] = max(Max[Z], p[Z]);
}
Make_BBox_from_min_max(Polyg->BBox, Min, Max);
if (fabs(Polyg->BBox.Lengths[X]) < Small_Tolerance)
{
Polyg->BBox.Lower_Left[X] -= Small_Tolerance;
Polyg->BBox.Lengths[X] += 2.0 * Small_Tolerance;
}
if (fabs(Polyg->BBox.Lengths[Y]) < Small_Tolerance)
{
Polyg->BBox.Lower_Left[Y] -= Small_Tolerance;
Polyg->BBox.Lengths[Y] += 2.0 * Small_Tolerance;
}
if (fabs(Polyg->BBox.Lengths[Z]) < Small_Tolerance)
{
Polyg->BBox.Lower_Left[Z] -= Small_Tolerance;
Polyg->BBox.Lengths[Z] += 2.0 * Small_Tolerance;
}
}
void Triangle::Compute_BBox()
{
Vector3d Min, Max, Epsilon;
Epsilon = Vector3d(EPSILON);
Min[X] = min3(P1[X], P2[X], P3[X]);
Min[Y] = min3(P1[Y], P2[Y], P3[Y]);
Min[Z] = min3(P1[Z], P2[Z], P3[Z]);
Max[X] = max3(P1[X], P2[X], P3[X]);
Max[Y] = max3(P1[Y], P2[Y], P3[Y]);
Max[Z] = max3(P1[Z], P2[Z], P3[Z]);
Min -= Epsilon;
Max += Epsilon;
Make_BBox_from_min_max(BBox, Min, Max);
}
void Compute_Triangle_BBox(TRIANGLE *Triangle)
{
VECTOR Min, Max, Epsilon;
Make_Vector(Epsilon, EPSILON, EPSILON, EPSILON);
Min[X] = min3(Triangle->P1[X], Triangle->P2[X], Triangle->P3[X]);
Min[Y] = min3(Triangle->P1[Y], Triangle->P2[Y], Triangle->P3[Y]);
Min[Z] = min3(Triangle->P1[Z], Triangle->P2[Z], Triangle->P3[Z]);
Max[X] = max3(Triangle->P1[X], Triangle->P2[X], Triangle->P3[X]);
Max[Y] = max3(Triangle->P1[Y], Triangle->P2[Y], Triangle->P3[Y]);
Max[Z] = max3(Triangle->P1[Z], Triangle->P2[Z], Triangle->P3[Z]);
VSubEq(Min, Epsilon);
VAddEq(Max, Epsilon);
Make_BBox_from_min_max(Triangle->BBox, Min, Max);
}
void Recompute_Inverse_BBox(BoundingBox *bbox, const TRANSFORM *trans)
{
int i;
Vector3d lower_left, lengths, corner;
Vector3d mins, maxs;
if(trans == NULL)
return;
lower_left = Vector3d(bbox->lowerLeft);
lengths = Vector3d(bbox->size);
mins = Vector3d(BOUND_HUGE);
maxs = Vector3d(-BOUND_HUGE);
for(i = 1; i <= 8; i++)
{
corner = lower_left;
corner[X] += ((i & 1) ? lengths[X] : 0.0);
corner[Y] += ((i & 2) ? lengths[Y] : 0.0);
corner[Z] += ((i & 4) ? lengths[Z] : 0.0);
MInvTransPoint(corner, corner, trans);
if(corner[X] < mins[X]) { mins[X] = corner[X]; }
if(corner[X] > maxs[X]) { maxs[X] = corner[X]; }
if(corner[Y] < mins[Y]) { mins[Y] = corner[Y]; }
if(corner[Y] > maxs[Y]) { maxs[Y] = corner[Y]; }
if(corner[Z] < mins[Z]) { mins[Z] = corner[Z]; }
if(corner[Z] > maxs[Z]) { maxs[Z] = corner[Z]; }
}
// Clip bounding box at the largest allowed bounding box.
if(mins[X] < -BOUND_HUGE / 2) { mins[X] = -BOUND_HUGE / 2; }
if(mins[Y] < -BOUND_HUGE / 2) { mins[Y] = -BOUND_HUGE / 2; }
if(mins[Z] < -BOUND_HUGE / 2) { mins[Z] = -BOUND_HUGE / 2; }
if(maxs[X] > BOUND_HUGE / 2) { maxs[X] = BOUND_HUGE / 2; }
if(maxs[Y] > BOUND_HUGE / 2) { maxs[Y] = BOUND_HUGE / 2; }
if(maxs[Z] > BOUND_HUGE / 2) { maxs[Z] = BOUND_HUGE / 2; }
Make_BBox_from_min_max(*bbox, mins, maxs);
}
void Polygon::Compute_BBox()
{
int i;
Vector3d p, Puv, Min, Max;
Min[X] = Min[Y] = Min[Z] = BOUND_HUGE;
Max[X] = Max[Y] = Max[Z] = -BOUND_HUGE;
for (i = 0; i < Data->Number; i++)
{
Puv[X] = Data->Points[i][X];
Puv[Y] = Data->Points[i][Y];
Puv[Z] = 0.0;
MTransPoint(p, Puv, Trans);
Min = min(Min, p);
Max = max(Max, p);
}
Make_BBox_from_min_max(BBox, Min, Max);
if (fabs(BBox.size[X]) < SMALL_TOLERANCE)
{
BBox.lowerLeft[X] -= SMALL_TOLERANCE;
BBox.size[X] += 2.0 * SMALL_TOLERANCE;
}
if (fabs(BBox.size[Y]) < SMALL_TOLERANCE)
{
BBox.lowerLeft[Y] -= SMALL_TOLERANCE;
BBox.size[Y] += 2.0 * SMALL_TOLERANCE;
}
if (fabs(BBox.size[Z]) < SMALL_TOLERANCE)
{
BBox.lowerLeft[Z] -= SMALL_TOLERANCE;
BBox.size[Z] += 2.0 * SMALL_TOLERANCE;
}
}
void BicubicPatch::Compute_BBox()
{
int i, j;
Vector3d Min, Max;
Min = Vector3d(BOUND_HUGE);
Max = Vector3d(-BOUND_HUGE);
for (i = 0; i < 4; i++)
{
for (j = 0; j < 4; j++)
{
Min[X] = min(Min[X], Control_Points[i][j][X]);
Min[Y] = min(Min[Y], Control_Points[i][j][Y]);
Min[Z] = min(Min[Z], Control_Points[i][j][Z]);
Max[X] = max(Max[X], Control_Points[i][j][X]);
Max[Y] = max(Max[Y], Control_Points[i][j][Y]);
Max[Z] = max(Max[Z], Control_Points[i][j][Z]);
}
}
Make_BBox_from_min_max(BBox, Min, Max);
}
void Compute_Bicubic_Patch_BBox(BICUBIC_PATCH *Bicubic_Patch)
{
int i, j;
VECTOR Min, Max;
Make_Vector(Min, BOUND_HUGE, BOUND_HUGE, BOUND_HUGE);
Make_Vector(Max, -BOUND_HUGE, -BOUND_HUGE, -BOUND_HUGE);
for (i = 0; i < 4; i++)
{
for (j = 0; j < 4; j++)
{
Min[X] = min(Min[X], Bicubic_Patch->Control_Points[i][j][X]);
Min[Y] = min(Min[Y], Bicubic_Patch->Control_Points[i][j][Y]);
Min[Z] = min(Min[Z], Bicubic_Patch->Control_Points[i][j][Z]);
Max[X] = max(Max[X], Bicubic_Patch->Control_Points[i][j][X]);
Max[Y] = max(Max[Y], Bicubic_Patch->Control_Points[i][j][Y]);
Max[Z] = max(Max[Z], Bicubic_Patch->Control_Points[i][j][Z]);
}
}
Make_BBox_from_min_max(Bicubic_Patch->BBox, Min, Max);
}
void Compute_Quadric_BBox(QUADRIC *Quadric, VECTOR ClipMin, VECTOR ClipMax)
{
DBL A, B, C, D, E, F, G, H, I, J;
DBL a, b, c, d;
DBL rx, ry, rz, rx1, rx2, ry1, ry2, rz1, rz2, x, y, z;
DBL New_Volume, Old_Volume;
VECTOR Min, Max, TmpMin, TmpMax, NewMin, NewMax, T1;
BBOX Old;
OBJECT *Sib;
/*
* Check for 'normal' form. If the quadric isn't in it's normal form
* we can't do anything (we could, but that would be to tedious!
* Diagonalising the quadric's 4x4 matrix, i.e. finding its eigenvalues
* and eigenvectors -> solving a 4th order polynom).
*/
/* Get quadrics coefficients. */
A = Quadric->Square_Terms[X];
E = Quadric->Square_Terms[Y];
H = Quadric->Square_Terms[Z];
B = Quadric->Mixed_Terms[X] / 2.0;
C = Quadric->Mixed_Terms[Y] / 2.0;
F = Quadric->Mixed_Terms[Z] / 2.0;
D = Quadric->Terms[X] / 2.0;
G = Quadric->Terms[Y] / 2.0;
I = Quadric->Terms[Z] / 2.0;
J = Quadric->Constant;
/* Set small values to 0. */
if (fabs(A) < EPSILON) A = 0.0;
if (fabs(B) < EPSILON) B = 0.0;
if (fabs(C) < EPSILON) C = 0.0;
if (fabs(D) < EPSILON) D = 0.0;
if (fabs(E) < EPSILON) E = 0.0;
if (fabs(F) < EPSILON) F = 0.0;
if (fabs(G) < EPSILON) G = 0.0;
if (fabs(H) < EPSILON) H = 0.0;
if (fabs(I) < EPSILON) I = 0.0;
if (fabs(J) < EPSILON) J = 0.0;
/* Non-zero mixed terms --> return */
if ((B != 0.0) || (C != 0.0) || (F != 0.0))
{
return;
}
/* Non-zero linear terms --> get translation vector */
if ((D != 0.0) || (G != 0.0) || (I != 0.0))
{
if (A != 0.0)
{
T1[X] = -D / A;
}
else
{
if (D != 0.0)
{
T1[X] = J / (2.0 * D);
}
else
{
T1[X] = 0.0;
}
}
if (E != 0.0)
{
T1[Y] = -G / E;
}
else
{
if (G != 0.0)
{
T1[Y] = J / (2.0 * G);
}
else
{
T1[Y] = 0.0;
}
}
if (H != 0.0)
{
T1[Z] = -I / H;
}
else
{
if (I != 0.0)
{
T1[Z] = J / (2.0 * I);
}
else
{
T1[Z] = 0.0;
}
}
/* Recalculate coefficients. */
D += A * T1[X];
G += E * T1[Y];
I += H * T1[Z];
J -= T1[X]*(A*T1[X] + 2.0*D) + T1[Y]*(E*T1[Y] + 2.0*G) + T1[Z]*(H*T1[Z] + 2.0*I);
}
else
{
Make_Vector(T1, 0.0, 0.0, 0.0);
}
/* Get old bounding box. */
Old = Quadric->BBox;
/* Init new bounding box. */
NewMin[X] = NewMin[Y] = NewMin[Z] = -BOUND_HUGE/2;
NewMax[X] = NewMax[Y] = NewMax[Z] = BOUND_HUGE/2;
/* Get the bounding box of the clipping object. */
if (Quadric->Clip != NULL)
{
Min[X] = Min[Y] = Min[Z] = -BOUND_HUGE;
Max[X] = Max[Y] = Max[Z] = BOUND_HUGE;
/* Intersect the members bounding boxes. */
for (Sib = Quadric->Clip; Sib != NULL; Sib = Sib->Sibling)
{
if (!Test_Flag(Sib, INVERTED_FLAG))
{
if (Sib->Methods == &Plane_Methods)
{
Compute_Plane_Min_Max((PLANE *)Sib, TmpMin, TmpMax);
}
else
{
Make_min_max_from_BBox(TmpMin, TmpMax, Sib->BBox);
}
Min[X] = max(Min[X], TmpMin[X]);
Min[Y] = max(Min[Y], TmpMin[Y]);
Min[Z] = max(Min[Z], TmpMin[Z]);
Max[X] = min(Max[X], TmpMax[X]);
Max[Y] = min(Max[Y], TmpMax[Y]);
Max[Z] = min(Max[Z], TmpMax[Z]);
}
}
Assign_Vector(ClipMin, Min);
Assign_Vector(ClipMax, Max);
}
/* Translate clipping box. */
VSubEq(ClipMin, T1);
VSubEq(ClipMax, T1);
/* We want A to be non-negative. */
if (A < 0.0)
{
A = -A;
D = -D;
E = -E;
G = -G;
H = -H;
I = -I;
J = -J;
}
/*
*
* Check for ellipsoid.
*
* x*x y*y z*z
* ----- + ----- + ----- - 1 = 0
* a*a b*b c*c
*
*/
if ((A > 0.0) && (E > 0.0) && (H > 0.0) && (J < 0.0))
{
a = sqrt(-J/A);
b = sqrt(-J/E);
c = sqrt(-J/H);
NewMin[X] = -a;
NewMin[Y] = -b;
NewMin[Z] = -c;
NewMax[X] = a;
NewMax[Y] = b;
NewMax[Z] = c;
}
/*
*
* Check for cylinder (x-axis).
*
* y*y z*z
* ----- + ----- - 1 = 0
* b*b c*c
*
*/
if ((A == 0.0) && (E > 0.0) && (H > 0.0) && (J < 0.0))
{
b = sqrt(-J/E);
c = sqrt(-J/H);
NewMin[Y] = -b;
NewMin[Z] = -c;
NewMax[Y] = b;
NewMax[Z] = c;
}
/*
*
* Check for cylinder (y-axis).
*
* x*x z*z
* ----- + ----- - 1 = 0
* a*a c*c
*
*/
if ((A > 0.0) && (E == 0.0) && (H > 0.0) && (J < 0.0))
{
a = sqrt(-J/A);
c = sqrt(-J/H);
NewMin[X] = -a;
NewMin[Z] = -c;
NewMax[X] = a;
NewMax[Z] = c;
}
/*
*
* Check for cylinder (z-axis).
*
* x*x y*y
* ----- + ----- - 1 = 0
* a*a b*b
*
*/
if ((A > 0.0) && (E > 0.0) && (H == 0.0) && (J < 0.0))
{
a = sqrt(-J/A);
b = sqrt(-J/E);
NewMin[X] = -a;
NewMin[Y] = -b;
NewMax[X] = a;
NewMax[Y] = b;
}
/*
*
* Check for cone (x-axis).
*
* x*x y*y z*z
* ----- - ----- - ----- = 0
* a*a b*b c*c
*
*/
if ((A > 0.0) && (E < 0.0) && (H < 0.0) && (J == 0.0))
{
a = sqrt(1.0/A);
b = sqrt(-1.0/E);
c = sqrt(-1.0/H);
/* Get radii for lower x value. */
x = ClipMin[X];
ry1 = fabs(x * b / a);
rz1 = fabs(x * c / a);
/* Get radii for upper x value. */
x = ClipMax[X];
ry2 = fabs(x * b / a);
rz2 = fabs(x * c / a);
ry = max(ry1, ry2);
rz = max(rz1, rz2);
NewMin[Y] = -ry;
NewMin[Z] = -rz;
NewMax[Y] = ry;
NewMax[Z] = rz;
}
/*
*
* Check for cone (y-axis).
*
* x*x y*y z*z
* ----- - ----- + ----- = 0
* a*a b*b c*c
*
*/
if ((A > 0.0) && (E < 0.0) && (H > 0.0) && (J == 0.0))
{
a = sqrt(1.0/A);
b = sqrt(-1.0/E);
c = sqrt(1.0/H);
/* Get radii for lower y value. */
y = ClipMin[Y];
rx1 = fabs(y * a / b);
rz1 = fabs(y * c / b);
/* Get radii for upper y value. */
y = ClipMax[Y];
rx2 = fabs(y * a / b);
rz2 = fabs(y * c / b);
rx = max(rx1, rx2);
rz = max(rz1, rz2);
NewMin[X] = -rx;
NewMin[Z] = -rz;
NewMax[X] = rx;
NewMax[Z] = rz;
}
/*
*
* Check for cone (z-axis).
*
* x*x y*y z*z
* ----- + ----- - ----- = 0
* a*a b*b c*c
*
*/
if ((A > 0.0) && (E > 0.0) && (H < 0.0) && (J == 0.0))
{
a = sqrt(1.0/A);
b = sqrt(1.0/E);
c = sqrt(-1.0/H);
/* Get radii for lower z value. */
z = ClipMin[Z];
rx1 = fabs(z * a / c);
ry1 = fabs(z * b / c);
/* Get radii for upper z value. */
z = ClipMax[Z];
rx2 = fabs(z * a / c);
ry2 = fabs(z * b / c);
rx = max(rx1, rx2);
ry = max(ry1, ry2);
NewMin[X] = -rx;
NewMin[Y] = -ry;
NewMax[X] = rx;
NewMax[Y] = ry;
}
/*
*
* Check for hyperboloid (x-axis).
*
* x*x y*y z*z
* ----- - ----- - ----- + 1 = 0
* a*a b*b c*c
*
*/
if ((A > 0.0) && (E < 0.0) && (H < 0.0) && (J > 0.0))
{
/* Get radii for lower x value. */
x = ClipMin[X];
d = 1.0 + A * Sqr(x);
ry1 = sqrt(-d / E);
rz1 = sqrt(-d / H);
/* Get radii for upper x value. */
x = ClipMax[X];
d = 1.0 + A * Sqr(x);
ry2 = sqrt(-d / E);
rz2 = sqrt(-d / H);
ry = max(ry1, ry2);
rz = max(rz1, rz2);
NewMin[Y] = -ry;
NewMin[Z] = -rz;
NewMax[Y] = ry;
NewMax[Z] = rz;
}
/*
*
* Check for hyperboloid (y-axis).
*
* x*x y*y z*z
* ----- - ----- + ----- - 1 = 0
* a*a b*b c*c
*
*/
if ((A > 0.0) && (E < 0.0) && (H > 0.0) && (J < 0.0))
{
/* Get radii for lower y value. */
y = ClipMin[Y];
d = 1.0 - E * Sqr(y);
rx1 = sqrt(d / A);
rz1 = sqrt(d / H);
/* Get radii for upper y value. */
y = ClipMax[Y];
d = 1.0 - E * Sqr(y);
rx2 = sqrt(d / A);
rz2 = sqrt(d / H);
rx = max(rx1, rx2);
rz = max(rz1, rz2);
NewMin[X] = -rx;
NewMin[Z] = -rz;
NewMax[X] = rx;
NewMax[Z] = rz;
}
/*
*
* Check for hyperboloid (z-axis).
*
* x*x y*y z*z
* ----- + ----- - ----- - 1 = 0
* a*a b*b c*c
*
*/
if ((A > 0.0) && (E > 0.0) && (H < 0.0) && (J < 0.0))
{
/* Get radii for lower z value. */
z = ClipMin[Z];
d = 1.0 - H * Sqr(z);
rx1 = sqrt(d / A);
ry1 = sqrt(d / E);
/* Get radii for upper z value. */
z = ClipMax[Z];
d = 1.0 - H * Sqr(z);
rx2 = sqrt(d / A);
ry2 = sqrt(d / E);
rx = max(rx1, rx2);
ry = max(ry1, ry2);
NewMin[X] = -rx;
NewMin[Y] = -ry;
NewMax[X] = rx;
NewMax[Y] = ry;
}
/*
*
* Check for paraboloid (x-axis).
*
* y*y z*z
* x - ----- - ----- = 0
* b*b c*c
*
*/
if ((A == 0.0) && (D != 0.0) && (E != 0.0) && (H != 0.0) && (J == 0.0))
{
/* Get radii for lower x value. */
x = ClipMin[X];
ry1 = sqrt(fabs(2.0 * D * x / E));
rz1 = sqrt(fabs(2.0 * D * x / H));
/* Get radii for upper x value. */
x = ClipMax[X];
ry2 = sqrt(fabs(2.0 * D * x / E));
rz2 = sqrt(fabs(2.0 * D * x / H));
ry = max(ry1, ry2);
rz = max(rz1, rz2);
NewMin[Y] = -ry;
NewMin[Z] = -rz;
NewMax[Y] = ry;
NewMax[Z] = rz;
}
/*
*
* Check for paraboloid (y-axis).
*
* x*x z*z
* y - ----- - ----- = 0
* a*a c*c
*
*/
if ((E == 0.0) && (G != 0.0) && (A != 0.0) && (H != 0.0) && (J == 0.0))
{
/* Get radii for lower y-value. */
y = ClipMin[Y];
rx1 = sqrt(fabs(2.0 * G * y / A));
rz1 = sqrt(fabs(2.0 * G * y / H));
/* Get radii for upper y value. */
y = ClipMax[Y];
rx2 = sqrt(fabs(2.0 * G * y / A));
rz2 = sqrt(fabs(2.0 * G * y / H));
rx = max(rx1, rx2);
rz = max(rz1, rz2);
NewMin[X] = -rx;
NewMin[Z] = -rz;
NewMax[X] = rx;
NewMax[Z] = rz;
}
/*
*
* Check for paraboloid (z-axis).
*
* x*x y*y
* z - ----- - ----- = 0
* a*a b*b
*
*/
if ((H == 0.0) && (I != 0.0) && (A != 0.0) && (E != 0.0) && (J == 0.0))
{
/* Get radii for lower z-value. */
z = ClipMin[Z];
rx1 = sqrt(fabs(2.0 * I * z / A));
ry1 = sqrt(fabs(2.0 * I * z / E));
/* Get radii for upper z value. */
z = ClipMax[Z];
rx2 = sqrt(fabs(2.0 * I * z / A));
ry2 = sqrt(fabs(2.0 * I * z / E));
rx = max(rx1, rx2);
ry = max(ry1, ry2);
NewMin[X] = -rx;
NewMin[Y] = -ry;
NewMax[X] = rx;
NewMax[Y] = ry;
}
/* Intersect clipping object's and quadric's bounding boxes */
NewMin[X] = max(NewMin[X], ClipMin[X]);
NewMin[Y] = max(NewMin[Y], ClipMin[Y]);
NewMin[Z] = max(NewMin[Z], ClipMin[Z]);
NewMax[X] = min(NewMax[X], ClipMax[X]);
NewMax[Y] = min(NewMax[Y], ClipMax[Y]);
NewMax[Z] = min(NewMax[Z], ClipMax[Z]);
/* Use old or new bounding box? */
New_Volume = (NewMax[X] - NewMin[X]) * (NewMax[Y] - NewMin[Y]) * (NewMax[Z] - NewMin[Z]);
BOUNDS_VOLUME(Old_Volume, Old);
if (New_Volume < Old_Volume)
{
/* Add translation. */
Quadric->Automatic_Bounds = true;
VAddEq(NewMin, T1);
VAddEq(NewMax, T1);
Make_BBox_from_min_max(Quadric->BBox, NewMin, NewMax);
/* Beware of bounding boxes to large. */
if ((Quadric->BBox.Lengths[X] > CRITICAL_LENGTH) ||
(Quadric->BBox.Lengths[Y] > CRITICAL_LENGTH) ||
(Quadric->BBox.Lengths[Z] > CRITICAL_LENGTH))
{
Make_BBox(Quadric->BBox, -BOUND_HUGE/2, -BOUND_HUGE/2, -BOUND_HUGE/2,
BOUND_HUGE, BOUND_HUGE, BOUND_HUGE);
}
}
}