bool Frustum::TestSweptSphere( const SVector3& pos, float radius, const SVector3& sweepDir ) const
{
// algorithm -- get all 12 intersection points of the swept sphere with the view frustum
// for all points >0, displace sphere along the sweep direction. if the displaced sphere
// is inside the frustum, return true. else, return false
float displacements[12];
int cnt = 0;
float a, b;
bool inFrustum = false;
for (int i=0; i<6; i++)
{
if (SweptSpherePlaneIntersect(a, b, camPlanes[i], pos, radius, sweepDir))
{
if (a>=0.f)
displacements[cnt++] = a;
if (b>=0.f)
displacements[cnt++] = b;
}
}
for (int i=0; i<cnt; i++)
{
SVector3 displPos = pos + sweepDir * displacements[i];
float displRadius = radius * 1.1f;
inFrustum |= TestSphere( displPos, displRadius );
}
return inFrustum;
}
plCullNode::plCullStatus plCullNode::ITestSphereRecur(const hsPoint3& center, float rad) const
{
plCullNode::plCullStatus retVal = TestSphere(center, rad);
// No Children, what we say goes.
if( (fOuterChild < 0) && (fInnerChild < 0) )
return retVal;
// No innerchild. If we cull, it's culled, else we
// hope our outerchild culls it.
if( fInnerChild < 0 )
{
if( retVal == kCulled )
return kCulled;
return IGetNode(fOuterChild)->ITestSphereRecur(center, rad);
}
// No outerchild. If we say it's clear, it's clear (or split), but if
// it's culled, we have to pass it to innerchild, who may pronounce it clear
if( fOuterChild < 0 )
{
if( retVal == kClear )
return kClear;
if( retVal == kSplit )
return kSplit;
return IGetNode(fInnerChild)->ITestSphereRecur(center, rad);
}
// We've got both children to feed.
// We pass the clear ones to the inner child, culled to outer,
// and split to both. Remember, a both children have to agree to cull a split.
if( retVal == kClear )
return IGetNode(fOuterChild)->ITestSphereRecur(center, rad);
if( retVal == kCulled )
return IGetNode(fInnerChild)->ITestSphereRecur(center, rad);
// Here's the split, to be culled, both children have to
// say its culled.
if( kCulled != IGetNode(fOuterChild)->ITestSphereRecur(center, rad) )
return kSplit;
if( kCulled != IGetNode(fInnerChild)->ITestSphereRecur(center, rad) )
return kSplit;
return kCulled;
}
