public bool RayCastStackless(int index)
{
LBVHNODE current = NativeNodes[0];
float3 rayDirection = Rays[index].Direction;
// ----------------------------------------------------------------------------------------------------
float sA = rayDirection[current.SplitAxis];
current.NearNodeID = math.@select(current.LChildID, current.RChildID, sA < 0f);
current.FarNodeID = math.@select(current.RChildID, current.LChildID, sA < 0f);
// ----------------------------------------------------------------------------------------------------
int rootNearID = current.NearNodeID;
int rootNodeID = current.NodeID;
current = NativeNodes[rootNearID];
TraverseState state = TraverseState.FromParent;
bool intersect = false;
while (current.NodeID != rootNodeID)
{
switch (state)
{
case TraverseState.FromChild:
int cID = current.NodeID;
current = NativeNodes[current.ParentID];
// ----------------------------------------------------------------------------------------------------
sA = rayDirection[current.SplitAxis];
current.NearNodeID = math.@select(current.LChildID, current.RChildID, sA < 0f);
current.FarNodeID = math.@select(current.RChildID, current.LChildID, sA < 0f);
// ----------------------------------------------------------------------------------------------------
if (cID == current.NearNodeID)
{
current = NativeNodes[current.FarNodeID];
state = TraverseState.FromSibling;
}
else
{
state = TraverseState.FromChild;
}
break;
case TraverseState.FromSibling:
// ReSharper disable once NotAccessedVariable
float dist;
if (!BVHBBox.IntersectRay(Rays[index], current.BMin, current.BMax, out dist))
{
current = NativeNodes[current.ParentID];
state = TraverseState.FromChild;
}
else if (current.IsLeaf == 1)
{
if (NativePrims[current.PrimitivesOffset].IntersectRay(Rays[index], ref TempHi, index))
{
HitInfos.Add(TempHi[index]);
intersect = true;
}
current = NativeNodes[current.ParentID];
state = TraverseState.FromChild;
}
else
{
// ----------------------------------------------------------------------------------------------------
sA = rayDirection[current.SplitAxis];
current.NearNodeID = math.@select(current.LChildID, current.RChildID, sA < 0f);
current.FarNodeID = math.@select(current.RChildID, current.LChildID, sA < 0f);
// ----------------------------------------------------------------------------------------------------
current = NativeNodes[current.NearNodeID];
state = TraverseState.FromParent;
}
break;
case TraverseState.FromParent:
if (!BVHBBox.IntersectRay(Rays[index], current.BMin, current.BMax, out dist))
{
cID = current.NodeID;
current = NativeNodes[current.ParentID];
// ----------------------------------------------------------------------------------------------------
sA = rayDirection[current.SplitAxis];
current.NearNodeID = math.@select(current.LChildID, current.RChildID, sA < 0f);
current.FarNodeID = math.@select(current.RChildID, current.LChildID, sA < 0f);
// ----------------------------------------------------------------------------------------------------
if (cID == current.NearNodeID)
{
current = NativeNodes[current.FarNodeID];
state = TraverseState.FromSibling;
}
else
{
current = NativeNodes[current.NearNodeID];
state = TraverseState.FromSibling;
}
}
else if (current.IsLeaf == 1)
{
// Test triangle for intersection
if (NativePrims[current.PrimitivesOffset].IntersectRay(Rays[index], ref TempHi, index))
{
HitInfos.Add(TempHi[index]);
intersect = true;
}
// ----------------------------------------------------------------------------------------------------
int lChild, rChild, splitAxis;
NativeNodes[current.ParentID]
.GetChildrenIDsAndSplitAxis(out lChild, out rChild, out splitAxis);
sA = rayDirection[splitAxis];
//int nearNodeID = math.@select(lChild, rChild, sA < 0f);
int farNodeID = math.@select(rChild, lChild, sA < 0f);
// ----------------------------------------------------------------------------------------------------
current = NativeNodes[farNodeID];
state = TraverseState.FromSibling;
}
else
{
// ----------------------------------------------------------------------------------------------------
sA = rayDirection[current.SplitAxis];
current.NearNodeID = math.@select(current.LChildID, current.RChildID, sA < 0f);
current.FarNodeID = math.@select(current.RChildID, current.LChildID, sA < 0f);
// ----------------------------------------------------------------------------------------------------
current = NativeNodes[current.NearNodeID];
state = TraverseState.FromParent;
}
break;
}
}
return(intersect);
}
public bool RayCast(int index, int nodeID)
{
if (NativeNodes[nodeID].IsLeaf == 1)
{
float bestDist = float.MaxValue;
HitInfo hitInfo = new HitInfo();
for (int i = 0; i < NativeNodes[nodeID].PrimitivesCount; i++)
{
hitInfo.Clear();
if (NativePrims[NativeNodes[nodeID].PrimitivesOffset + i].IntersectRay(Rays[index], out hitInfo))
{
if (hitInfo.HitDistance < bestDist)
{
bestDist = hitInfo.HitDistance;
HitInfos.Add(new HitInfo(hitInfo));
}
}
}
}
else
{
// ReSharper disable once NotAccessedVariable
float hitDist;
if (BVHBBox.IntersectRay(Rays[index], NativeNodes[nodeID].BMin, NativeNodes[nodeID].BMax, out hitDist))
{
float d1;
float d2;
int lNodeID = NativeNodes[nodeID].LChildID;
int rNodeID = NativeNodes[nodeID].RChildID;
bool bHitL = BVHBBox.IntersectRay(Rays[index], NativeNodes[lNodeID].BMin, NativeNodes[lNodeID].BMax,
out d1);
bool bHitR = BVHBBox.IntersectRay(Rays[index], NativeNodes[rNodeID].BMin, NativeNodes[rNodeID].BMax,
out d2);
if (bHitL && bHitR)
{
if (d1 > d2)
{
RayCast(index, lNodeID);
RayCast(index, rNodeID);
}
else
{
RayCast(index, rNodeID);
RayCast(index, lNodeID);
}
}
else if (bHitL)
{
RayCast(index, lNodeID);
}
else if (bHitR)
{
RayCast(index, rNodeID);
}
}
}
return(false);
}