public Box3f(AxisAlignedBox3f aaBox)
{
Extent = 0.5f * aaBox.Diagonal;
Center = aaBox.Min + Extent;
AxisX = Vector3f.AxisX;
AxisY = Vector3f.AxisY;
AxisZ = Vector3f.AxisZ;
}
public Box3f(AxisAlignedBox3f aaBox)
{
// [RMS] this should produce Empty for aaBox.Empty...
Extent = new Vector3f(aaBox.Width * 0.5f, aaBox.Height * 0.5f, aaBox.Depth * 0.5f);
Center = aaBox.Center;
AxisX = Vector3f.AxisX;
AxisY = Vector3f.AxisY;
AxisZ = Vector3f.AxisZ;
}
public static AxisAlignedBox3f Bounds <T>(IEnumerable <T> values, Func <T, Vector3f> PositionF)
{
AxisAlignedBox3f box = AxisAlignedBox3f.Empty;
foreach (T t in values)
{
box.Contain(PositionF(t));
}
return(box);
}
public static AxisAlignedBox3f Bounds(IEnumerable <Vector3f> positions)
{
AxisAlignedBox3f box = AxisAlignedBox3f.Empty;
foreach (Vector3f v in positions)
{
box.Contain(v);
}
return(box);
}
int split_tri_set_sorted(int[] triangles, Vector3d[] centers, int iStart, int iCount, int depth, int minTriCount,
boxes_set tris, boxes_set nodes, out AxisAlignedBox3f box)
{
box = AxisAlignedBox3f.Empty;
int iBox = -1;
if (iCount < minTriCount)
{
// append new triangles box
iBox = tris.iBoxCur++;
tris.box_to_index.insert(tris.iIndicesCur, iBox);
tris.index_list.insert(iCount, tris.iIndicesCur++);
for (int i = 0; i < iCount; ++i)
{
tris.index_list.insert(triangles[iStart + i], tris.iIndicesCur++);
box.Contain(mesh.GetTriBounds(triangles[iStart + i]));
}
tris.box_centers.insert(box.Center, iBox);
tris.box_extents.insert(box.Extents, iBox);
return(-(iBox + 1));
}
AxisComp c = new AxisComp()
{
Axis = depth % 3
};
Array.Sort(centers, triangles, iStart, iCount, c);
int mid = iCount / 2;
int n0 = mid;
int n1 = iCount - mid;
// create child boxes
AxisAlignedBox3f box1;
int child0 = split_tri_set_sorted(triangles, centers, iStart, n0, depth + 1, minTriCount, tris, nodes, out box);
int child1 = split_tri_set_sorted(triangles, centers, iStart + mid, n1, depth + 1, minTriCount, tris, nodes, out box1);
box.Contain(box1);
// append new box
iBox = nodes.iBoxCur++;
nodes.box_to_index.insert(nodes.iIndicesCur, iBox);
nodes.index_list.insert(child0, nodes.iIndicesCur++);
nodes.index_list.insert(child1, nodes.iIndicesCur++);
nodes.box_centers.insert(box.Center, iBox);
nodes.box_extents.insert(box.Extents, iBox);
return(iBox);
}
// accumulate triangle counts and track each box-parent index.
// also checks that triangles are contained in boxes
private void test_coverage(int[] tri_counts, int[] parent_indices, int iBox)
{
int idx = box_to_index[iBox];
debug_check_child_tris_in_box(iBox);
if (idx < triangles_end)
{
// triange-list case, array is [N t1 t2 ... tN]
int n = index_list[idx];
AxisAlignedBox3f box = get_box(iBox);
for (int i = 1; i <= n; ++i)
{
int ti = index_list[idx + i];
tri_counts[ti]++;
Index3i tv = mesh.GetTriangle(ti);
for (int j = 0; j < 3; ++j)
{
Vector3f v = (Vector3f)mesh.GetVertex(tv[j]);
if (!box.Contains(v))
{
Util.gBreakToDebugger();
}
}
}
}
else
{
int i0 = index_list[idx];
if (i0 < 0)
{
// negative index means we only have one 'child' box to descend into
i0 = (-i0) - 1;
parent_indices[i0] = iBox;
test_coverage(tri_counts, parent_indices, i0);
}
else
{
// positive index, two sequential child box indices to descend into
i0 = i0 - 1;
parent_indices[i0] = iBox;
test_coverage(tri_counts, parent_indices, i0);
int i1 = index_list[idx + 1];
i1 = i1 - 1;
parent_indices[i1] = iBox;
test_coverage(tri_counts, parent_indices, i1);
}
}
}
public AxisAlignedBox3f Intersect(AxisAlignedBox3f box)
{
AxisAlignedBox3f intersect = new AxisAlignedBox3f(
Math.Max(Min.x, box.Min.x), Math.Max(Min.y, box.Min.y), Math.Max(Min.z, box.Min.z),
Math.Min(Max.x, box.Max.x), Math.Min(Max.y, box.Max.y), Math.Min(Max.z, box.Max.z));
if (intersect.Height <= 0 || intersect.Width <= 0 || intersect.Depth <= 0)
{
return(AxisAlignedBox3f.Empty);
}
else
{
return(intersect);
}
}
// Appends a box that contains free triangles in one-ring of vertex vid.
// If tri count is < spill threshold, push onto spill list instead.
// Returns # of free tris found.
int add_one_ring_box(int vid, byte[] used_triangles, int[] temp_tris,
ref int iBoxCur, ref int iIndicesCur,
DVector <int> spill, int nSpillThresh)
{
// collect free triangles
int num_free = 0;
foreach (int tid in mesh.VtxTrianglesItr(vid))
{
if (used_triangles[tid] == 0)
{
temp_tris[num_free++] = tid;
}
}
// none free, get out
if (num_free == 0)
{
return(0);
}
// if we only had a couple free triangles, wait and see if
// they get picked up by another vert
if (num_free < nSpillThresh)
{
spill.Add(vid);
return(num_free);
}
// append new box
AxisAlignedBox3f box = AxisAlignedBox3f.Empty;
int iBox = iBoxCur++;
box_to_index.insert(iIndicesCur, iBox);
index_list.insert(num_free, iIndicesCur++);
for (int i = 0; i < num_free; ++i)
{
index_list.insert(temp_tris[i], iIndicesCur++);
used_triangles[temp_tris[i]]++; // incrementing for sanity check below, just need to set to 1
box.Contain(mesh.GetTriBounds(temp_tris[i]));
}
box_centers.insert(box.Center, iBox);
box_extents.insert(box.Extents, iBox);
return(num_free);
}
public AxisAlignedBox3f ToAABB()
{
// [TODO] probably more efficient way to do this...at minimum can move center-shift
// to after the containments...
Vector3f extAxis0 = Extent.x * AxisX;
Vector3f extAxis1 = Extent.y * AxisY;
Vector3f extAxis2 = Extent.z * AxisZ;
AxisAlignedBox3f result = new AxisAlignedBox3f(Center - extAxis0 - extAxis1 - extAxis2);
result.Contain(Center + extAxis0 - extAxis1 - extAxis2);
result.Contain(Center + extAxis0 + extAxis1 - extAxis2);
result.Contain(Center - extAxis0 + extAxis1 - extAxis2);
result.Contain(Center - extAxis0 - extAxis1 + extAxis2);
result.Contain(Center + extAxis0 - extAxis1 + extAxis2);
result.Contain(Center + extAxis0 + extAxis1 + extAxis2);
result.Contain(Center - extAxis0 + extAxis1 + extAxis2);
return(result);
}
// do full tree traversal below iBox to make sure that all child triangles are contained
void debug_check_child_tris_in_box(int iBox)
{
AxisAlignedBox3f box = get_box(iBox);
TreeTraversal t = new TreeTraversal()
{
NextTriangleF = (tID) => {
Index3i tv = mesh.GetTriangle(tID);
for (int j = 0; j < 3; ++j)
{
Vector3f v = (Vector3f)mesh.GetVertex(tv[j]);
if (box.Contains(v) == false)
{
Util.gBreakToDebugger();
}
}
}
};
tree_traversal(iBox, 0, t);
}
int split_tri_set_midpoint(int[] triangles, Vector3d[] centers, int iStart, int iCount, int depth, int minTriCount,
boxes_set tris, boxes_set nodes, out AxisAlignedBox3f box)
{
box = AxisAlignedBox3f.Empty;
int iBox = -1;
if (iCount < minTriCount)
{
// append new triangles box
iBox = tris.iBoxCur++;
tris.box_to_index.insert(tris.iIndicesCur, iBox);
tris.index_list.insert(iCount, tris.iIndicesCur++);
for (int i = 0; i < iCount; ++i)
{
tris.index_list.insert(triangles[iStart + i], tris.iIndicesCur++);
box.Contain(mesh.GetTriBounds(triangles[iStart + i]));
}
tris.box_centers.insert(box.Center, iBox);
tris.box_extents.insert(box.Extents, iBox);
return(-(iBox + 1));
}
//compute interval along an axis and find midpoint
int axis = depth % 3;
Interval1d interval = Interval1d.Empty;
for (int i = 0; i < iCount; ++i)
{
interval.Contain(centers[iStart + i][axis]);
}
double midpoint = interval.Center;
int n0, n1;
if (Math.Abs(interval.a - interval.b) > MathUtil.ZeroTolerance)
{
// we have to re-sort the centers & triangles lists so that centers < midpoint
// are first, so that we can recurse on the two subsets. We walk in from each side,
// until we find two out-of-order locations, then we swap them.
int l = 0;
int r = iCount - 1;
while (l < r)
{
// [RMS] is <= right here? if v.axis == midpoint, then this loop
// can get stuck unless one of these has an equality test. But
// I did not think enough about if this is the right thing to do...
while (centers[iStart + l][axis] <= midpoint)
{
l++;
}
while (centers[iStart + r][axis] > midpoint)
{
r--;
}
if (l >= r)
{
break; //done!
}
//swap
Vector3d tmpc = centers[iStart + l]; centers[iStart + l] = centers[iStart + r]; centers[iStart + r] = tmpc;
int tmpt = triangles[iStart + l]; triangles[iStart + l] = triangles[iStart + r]; triangles[iStart + r] = tmpt;
}
n0 = l;
n1 = iCount - n0;
Debug.Assert(n0 >= 1 && n1 >= 1);
}
else
{
// interval is near-empty, so no point trying to do sorting, just split half and half
n0 = iCount / 2;
n1 = iCount - n0;
}
// create child boxes
AxisAlignedBox3f box1;
int child0 = split_tri_set_midpoint(triangles, centers, iStart, n0, depth + 1, minTriCount, tris, nodes, out box);
int child1 = split_tri_set_midpoint(triangles, centers, iStart + n0, n1, depth + 1, minTriCount, tris, nodes, out box1);
box.Contain(box1);
// append new box
iBox = nodes.iBoxCur++;
nodes.box_to_index.insert(nodes.iIndicesCur, iBox);
nodes.index_list.insert(child0, nodes.iIndicesCur++);
nodes.index_list.insert(child1, nodes.iIndicesCur++);
nodes.box_centers.insert(box.Center, iBox);
nodes.box_extents.insert(box.Extents, iBox);
return(iBox);
}
public bool Intersects(AxisAlignedBox3f box)
{
return(!((box.Max.x <= Min.x) || (box.Min.x >= Max.x) ||
(box.Max.y <= Min.y) || (box.Min.y >= Max.y) ||
(box.Max.z <= Min.z) || (box.Min.z >= Max.z)));
}
public void Contain(AxisAlignedBox3f box)
{
Contain(box.Min);
Contain(box.Max);
}
