// Utility function to figure out how well a subdivision point splits stuff
public int[,,] CheckSubdivision(Vec3 split)
{
int[, ,] results = new int[2, 2, 2];
double[][] array = new double[][]
{
new double[] { bounds.array[0][0], split.x, bounds.array[0][1] },
new double[] { bounds.array[1][0], split.y, bounds.array[1][1] },
new double[] { bounds.array[2][0], split.z, bounds.array[2][1] }
};
for (int i = 0; i < 2; i++)
{
for (int j = 0; j < 2; j++)
{
for (int k = 0; k < 2; k++)
{
AABB subregion = new AABB {
array = new double[][] { new double[] { array[0][i], array[0][i + 1] }, new double[] { array[1][j], array[1][j + 1] }, new double[] { array[2][k], array[2][k + 1] } }
};
foreach (Item item in items)
{
if (AABB.CheckIntersection(item.aabb, subregion))
{
results[i, j, k]++;
}
}
}
}
}
return(results);
}
// Interesting constructor
// Does the populating of the tree and whatnot automatically, given the objects to populate it with
public ModelIntersectTree(CSGModel a, CSGModel b)
{
AABB a_box = a.ComputeAABB();
AABB b_box = b.ComputeAABB();
if (!AABB.CheckIntersection(a_box, b_box))
{
return;
}
AABB intersection = AABB.Intersection(a_box, b_box);
BoundsInit(intersection, 5);
foreach (Octree.Item item in a.GetSourceTriangleOctreeData())
{
if (item.obj is CSGSourceTriangle)
{
allItems[0].Add((item.obj as CSGSourceTriangle).id);
InsertItem(0, item);
}
}
foreach (Octree.Item item in b.GetSourceTriangleOctreeData())
{
if (item.obj is CSGSourceTriangle)
{
allItems[1].Add((item.obj as CSGSourceTriangle).id);
InsertItem(1, item);
}
}
}
/// <summary>
/// 求se 与三角形边的交点，se在三角形平面上，其中 s在三角形内部，e 在三角形外部，一定有交点的。
/// </summary>
/// <param name="s"></param>
/// <param name="e"></param>
/// <returns></returns>
public bool GetLineIntersectPoint(Vector3 s, Vector3 e, ref Vector3 ret)
{
if (AABB.CheckIntersection(this.Parent.Normal, this.P1, this.P2, s, e, ref ret) == true)
{
return(true);
}
else if (AABB.CheckIntersection(this.Parent.Normal, this.P2, this.P3, s, e, ref ret) == true)
{
return(true);
}
else if (AABB.CheckIntersection(this.Parent.Normal, this.P3, this.P1, s, e, ref ret) == true)
{
return(true);
}
return(false);
}
// Inserts an item into the category-th list (possibly of children, based on the item's bounding box)
public void InsertItem(int category, Octree.Item item)
{
if (AABB.CheckIntersection(item.aabb, bounds))
{
items[category].Add(item);
if (children != null)
{
foreach (ModelIntersectTree grid in children)
{
grid.InsertItem(category, item);
}
}
if (children == null && max_subdivisions > 0)
{
Subdivide();
}
}
}
/// <summary>
/// 求se 与多边形边的交点，se在多边形平面上，其中 s在多边形内部，e 在多边形外部，一定有交点的。用于切换多边形处理
/// </summary>
/// <param name="s"></param>
/// <param name="e"></param>
/// <returns></returns>
public bool GetLineIntersectPoint(Vector3 s, Vector3 e, ref Vector3 ret)
{
if (m_ListPt == null || m_ListPt.Count < 3)
{
return(false);
}
for (int i = 0; i < m_ListPt.Count - 1; i++)
{
if (AABB.CheckIntersection(this.Normal, m_ListPt[i].Pos, m_ListPt[i + 1].Pos, s, e, ref ret) == true)
{
return(true);
}
}
if (AABB.CheckIntersection(this.Normal, m_ListPt[m_ListPt.Count - 1].Pos, m_ListPt[0].Pos, s, e, ref ret) == true)
{
return(true);
}
return(false);
}
// Inserts an item into the category-th list (possibly of children, based on the item's bounding box)
public void InsertItem(Item item)
{
if (AABB.CheckIntersection(item.aabb, bounds))
{
items.Add(item);
if (children != null)
{
foreach (Octree grid in children)
{
grid.InsertItem(item);
}
}
else if (ConditionallySubdivide())
{
Subdivide();
}
}
}
// Inserts an item into the category-th list (possibly of children, based on the item's bounding box)
public void InsertItem(int category, int item, AABB box)
{
if (AABB.CheckIntersection(box, bounds))
{
items[category].Add(item);
if (children == null && max_subdivisions > 0)
{
Subdivide();
}
if (children != null)
{
foreach (PartitioningGrid grid in children)
{
grid.InsertItem(category, item, box);
}
}
}
max_encountered_item[category] = Math.Max(max_encountered_item[category], item);
}
// Do the CSG stuff
// This is a virtual function, just in case someone thinks they can do it better
public virtual void Compute()
{
first_blob = ModelInput.FromBasicModelData(first_in, first_xform);
second_blob = ModelInput.FromBasicModelData(second_in, second_xform);
/*
* CSGModel derp1 = ModelUtil.ModelFromBMD(first_in, first_xform);
* CSGModel derp2 = ModelUtil.ModelFromBMD(second_in, second_xform);
* int count = 0;
* ModelIntersectTree.CullIntersections(derp1, derp2,
* (i, j) =>
* {
* count++;
* });
*/
AABB aa_box = first_blob.AABB;
AABB bb_box = second_blob.AABB;
if (AABB.CheckIntersection(aa_box, bb_box)) // check whether their bounding boxes even intersect... if they don't, most of the math can be skipped!
{
AABB intersection = AABB.Intersection(aa_box, bb_box);
PartitioningGrid grid = new PartitioningGrid(intersection, 5);
first_blob.PopulateGrid(grid, 0);
second_blob.PopulateGrid(grid, 1);
List <TrianglePair> pairs = new List <TrianglePair>();
grid.ForLeafLevelPairs(
(first, second) =>
{
pairs.Add(new TrianglePair {
a = first, b = second
});
});
Snip(first_blob, second_blob, pairs);
}
else
{
Snip(first_blob, second_blob, new List <TrianglePair>());
}
}