public static float SqrDistSegOBBInternal(Segment rkLine, CollisionOBB rkBox,
SegOBBParams pf)
{
// compute coordinates of line in box coordinate system
Vector3 kDiff = rkLine.origin - rkBox.center;
Vector3 kPnt = new Vector3(kDiff.Dot(rkBox.axes[0]),
kDiff.Dot(rkBox.axes[1]),
kDiff.Dot(rkBox.axes[2]));
Vector3 kDir = new Vector3(rkLine.direction.Dot(rkBox.axes[0]),
rkLine.direction.Dot(rkBox.axes[1]),
rkLine.direction.Dot(rkBox.axes[2]));
// Apply reflections so that direction vector has nonnegative components.
bool[] bReflect = new bool[3] { false, false, false };
int i;
for (i = 0; i < 3; i++) {
if (kDir[i] < 0.0f) {
kPnt[i] = -kPnt[i];
kDir[i] = -kDir[i];
bReflect[i] = true;
}
}
float fSqrDistance = 0.0f;
if (kDir.x > 0.0f) {
if (kDir.y > 0.0f) {
if (kDir.z > 0.0f) {
// (+,+,+)
CaseNoZeros(ref kPnt,kDir,rkBox,pf,ref fSqrDistance);
} else {
// (+,+,0)
Case0(0,1,2,ref kPnt,kDir,rkBox,pf,ref fSqrDistance);
}
} else {
if (kDir.z > 0.0f) {
// (+,0,+)
Case0(0,2,1,ref kPnt,kDir,rkBox,pf,ref fSqrDistance);
} else {
// (+,0,0)
Case00(0,1,2,ref kPnt,kDir,rkBox,pf,ref fSqrDistance);
}
}
} else {
if (kDir.y > 0.0f) {
if (kDir.z > 0.0f) {
// (0,+,+)
Case0(1,2,0,ref kPnt,kDir,rkBox,pf,ref fSqrDistance);
} else {
// (0,+,0)
Case00(1,0,2,ref kPnt,kDir,rkBox,pf,ref fSqrDistance);
}
} else {
if (kDir.z > 0.0f)
{
// (0,0,+)
Case00(2,0,1,ref kPnt,kDir,rkBox,pf,ref fSqrDistance);
} else {
// (0,0,0)
Case000(ref kPnt,rkBox,ref fSqrDistance);
if (pf.useIt)
pf.pfLParam = 0.0f;
}
}
}
if (pf.useIt) {
// undo reflections
for (i = 0; i < 3; i++) {
if (bReflect[i])
kPnt[i] = -kPnt[i];
}
pf.pfBVec = kPnt;
}
return fSqrDistance;
}
public static float SqrDistSegOBB(Segment rkSeg, CollisionOBB rkBox,
SegOBBParams pf)
{
Segment kLine = new Segment(rkSeg.origin, rkSeg.direction);
float fSqrDistance = SqrDistSegOBBInternal(kLine,rkBox,pf);
if (pf.pfLParam >= 0.0f) {
if (pf.pfLParam <= 1.0f) {
return fSqrDistance;
} else {
fSqrDistance = XSqDistPtOBB(rkSeg.origin + rkSeg.direction,rkBox,pf);
if (pf.useIt)
pf.pfLParam = 1.0f;
return fSqrDistance;
}
} else {
fSqrDistance = XSqDistPtOBB(rkSeg.origin,rkBox,pf);
if (pf.useIt)
pf.pfLParam = 0.0f;
return fSqrDistance;
}
}