private void Add(List <byte> voxelList, BoundingCube test, IOctTreeInsertable obj, double precision)
{
int ind = voxelList.Count;
voxelList.Add(0); // 0 means: this is a final voxel, belonging to the object (we know, test interferes with the object)
if (test.XDiff > precision)
{
BoundingCube[] sc = subCubes(test);
for (int i = 0; i < 8; i++)
{
if (obj.HitTest(ref sc[i], precision))
{
voxelList[ind] |= (byte)(1 << i); // this adds a subvoxel to the list, it is no more final
Add(voxelList, sc[i], obj, precision);
}
}
}
}
/// <summary>
/// Creates the voxel representation of the provided <paramref name="obj"/> (only GetExtent and HitTest are beeing used)
/// </summary>
/// <param name="obj">the object for which the voxel represenation is to be created</param>
/// <param name="precision">the precision, size of the smallest voxel</param>
public VoxelTree(IOctTreeInsertable obj, double precision)
{
BoundingCube ext = obj.GetExtent(precision);
BoundingCube unit = new BoundingCube(-1, 1, -1, 1, -1, 1);
baseCube = 1;
double size = 1;
while (unit.Contains(ext))
{
size /= 2;
baseCube--;
unit.Set(-size, size, -size, size, -size, size);
}
if (baseCube == 1)
{ // ext is not contained in -1..1
size = 2;
unit.Set(-2, 2, -2, 2, -2, 2);
while (!unit.Contains(ext))
{
size *= 2;
baseCube++;
unit.Set(-size, size, -size, size, -size, size);
}
}
if (baseCube >= 0)
{
size = 1 << baseCube;
}
else
{
size = 1.0 / (1 << -baseCube);
}
unit.Set(-size, size, -size, size, -size, size); // this BoundingCube contains the whole object
List <byte> startCubesList = new List <byte>();
do
{
byte found = 255;
BoundingCube[] sc = subCubes(unit);
for (byte i = 0; i < 8; i++)
{
if (sc[i].Contains(ext))
{
if (found == 255)
{
found = i;
}
else
{ // two different cubes contain ext, so we must stop here
found = 255;
break;
}
}
}
if (found != 255)
{
startCubesList.Add(found);
unit = sc[found];
}
else
{
break;
}
} while (true);
startCube = startCubesList.ToArray();
List <byte> voxelList = new List <byte>();
Add(voxelList, unit, obj, precision);
voxels = voxelList.ToArray();
}
