static Mesh PerformOperation(Mesh a, Mesh b, CsgFunctionHandler fun)
{
CsgNode A = new CsgNode(PolygonsFromMesh(a));
CsgNode B = new CsgNode(PolygonsFromMesh(b));
CsgNode AB = fun(A, B);
List <CsgPolygon> polygons = AB.GetAllPolygons();
return(MeshFromPolygons(polygons));
}
// Return a list of all polygons in this BSP tree.
public static int GetTotalPolygons(CsgNode root)
{
int total = 0;
if (root != null)
{
total += GetTotalPolygons(root.back);
total += GetTotalPolygons(root.front);
total += root.polygons.Count;
}
return(total);
}
// Remove all polygons in this BSP tree that are inside the other BSP tree
// `bsp`.
public void ClipTo(CsgNode other)
{
this.polygons = other.ClipPolygons(this.polygons);
if (this.front != null)
{
this.front.ClipTo(other);
}
if (this.back != null)
{
this.back.ClipTo(other);
}
}
// Return a new CSG solid representing space both this solid and in the
// solid `csg`. Neither this solid nor the solid `csg` are modified.
//
// A.intersect(B)
//
// +-------+
// | |
// | A |
// | +--+----+ = +--+
// +----+--+ | +--+
// | B |
// | |
// +-------+
//
public static CsgNode Intersect(CsgNode a1, CsgNode b1)
{
CsgNode a = a1.Clone();
CsgNode b = b1.Clone();
a.Invert();
b.ClipTo(a);
b.Invert();
a.ClipTo(b);
b.ClipTo(a);
a.BuildFromPolygons(b.GetAllPolygons());
a.Invert();
CsgNode ret = new CsgNode(a.GetAllPolygons());
return ret;
}
// Return a new CSG solid representing space in either this solid or in the
// solid `csg`. Neither this solid nor the solid `csg` are modified.
//
// +-------+ +-------+
// | | | |
// | A | | |
// | +--+----+ = | +----+
// +----+--+ | +----+ |
// | B | | |
// | | | |
// +-------+ +-------+
//
public static CsgNode Union(CsgNode a1, CsgNode b1)
{
CsgNode a = a1.Clone();
CsgNode b = b1.Clone();
a.ClipTo(b);
b.ClipTo(a);
b.Invert();
b.ClipTo(a);
b.Invert();
a.BuildFromPolygons(b.GetAllPolygons());
CsgNode ret = new CsgNode(a.GetAllPolygons());
return(ret);
}
public CsgNode Clone()
{
CsgNode ret = new CsgNode();
ret.polygons = this.polygons;
ret.plane = this.plane;
if (this.front != null)
{
ret.front = this.front.Clone();
}
if (this.back != null)
{
ret.back = this.back.Clone();
}
return(ret);
}
// Convert solid space to empty space and empty space to solid space.
public void Invert()
{
for (int i = 0; i < this.polygons.Count; i++)
{
this.polygons[i].flip();
}
this.plane.flip();
if (this.front != null)
{
this.front.Invert();
}
if (this.back != null)
{
this.back.Invert();
}
CsgNode hold = this.front;
this.front = this.back;
this.back = hold;
}
// Build a BSP tree out of `polygons`. When called on an existing tree, the
// new polygons are filtered down to the bottom of the tree and become new
// nodes there. Each set of polygons is partitioned using the first polygon
// (no heuristic is used to pick a good split).
public void BuildFromPolygons(List <CsgPolygon> list)
{
if (list.Count <= 0)
{
return;
}
if (!this.plane.ok())
{
this.plane = list[0].plane;
}
List <CsgPolygon> list_front = new List <CsgPolygon>();
List <CsgPolygon> list_back = new List <CsgPolygon>();
for (int i = 0; i < list.Count; i++)
{
this.plane.SplitPolygon(list[i], this.polygons, this.polygons, list_front, list_back);
int count = CsgNode.GetTotalPolygons(this);
}
if (list_front.Count > 0)
{
if (this.front == null)
{
this.front = new CsgNode();
}
this.front.BuildFromPolygons(list_front);
}
if (list_back.Count > 0)
{
if (this.back == null)
{
this.back = new CsgNode();
}
this.back.BuildFromPolygons(list_back);
}
}
// Convert solid space to empty space and empty space to solid space.
public void Invert()
{
for (int i = 0; i < this.polygons.Count; i++)
{
this.polygons[i].flip();
}
this.plane.flip();
if (this.front != null)
{
this.front.Invert();
}
if (this.back != null)
{
this.back.Invert();
}
CsgNode hold = this.front;
this.front = this.back;
this.back = hold;
}
public CsgNode(List<CsgPolygon> list)
{
front = null;
back = null;
BuildFromPolygons(list);
}
public CsgNode()
{
front = null;
back = null;
}
// Build a BSP tree out of `polygons`. When called on an existing tree, the
// new polygons are filtered down to the bottom of the tree and become new
// nodes there. Each set of polygons is partitioned using the first polygon
// (no heuristic is used to pick a good split).
public void BuildFromPolygons(List<CsgPolygon> list)
{
if (list.Count <= 0) return;
if (!this.plane.ok()) this.plane = list[0].plane;
List<CsgPolygon> list_front = new List<CsgPolygon>();
List<CsgPolygon> list_back = new List<CsgPolygon>();
for (int i = 0; i < list.Count; i++)
{
this.plane.SplitPolygon(list[i], this.polygons, this.polygons, list_front, list_back);
int count = CsgNode.GetTotalPolygons(this);
}
if (list_front.Count > 0)
{
if (this.front == null) this.front = new CsgNode();
this.front.BuildFromPolygons(list_front);
}
if (list_back.Count > 0)
{
if (this.back == null) this.back = new CsgNode();
this.back.BuildFromPolygons(list_back);
}
}
public CsgNode Clone()
{
CsgNode ret = new CsgNode();
ret.polygons = this.polygons;
ret.plane = this.plane;
if (this.front != null)
{
ret.front = this.front.Clone();
}
if (this.back != null)
{
ret.back = this.back.Clone();
}
return ret;
}
// Return a list of all polygons in this BSP tree.
public static int GetTotalPolygons(CsgNode root)
{
int total = 0;
if (root != null)
{
total += GetTotalPolygons(root.back);
total += GetTotalPolygons(root.front);
total += root.polygons.Count;
}
return total;
}
// Remove all polygons in this BSP tree that are inside the other BSP tree
// `bsp`.
public void ClipTo(CsgNode other)
{
this.polygons = other.ClipPolygons(this.polygons);
if (this.front != null)
{
this.front.ClipTo(other);
}
if (this.back != null)
{
this.back.ClipTo(other);
}
}
public CsgNode()
{
front = null;
back = null;
}
public CsgNode(List <CsgPolygon> list)
{
front = null;
back = null;
BuildFromPolygons(list);
}
private static Mesh PerformOperation(Mesh a, Mesh b, CsgFunctionHandler fun)
{
CsgNode A = new CsgNode(PolygonsFromMesh(a));
CsgNode B = new CsgNode(PolygonsFromMesh(b));
CsgNode AB = fun(A, B);
List<CsgPolygon> polygons = AB.GetAllPolygons();
return MeshFromPolygons(polygons);
}
