// 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 CSG intersect(CSG csg)
{
CSGNode a = new CSGNode(this.clone().polygons);
CSGNode b = new CSGNode(csg.clone().polygons);
a.invert();
b.clipTo(a);
b.invert();
a.clipTo(b);
b.clipTo(a);
a.addPolygons(b.allPolygons());
a.invert();
return(CSG.fromPolygons(a.allPolygons()));
}
// 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.union(B)
//
// +-------+ +-------+
// | | | |
// | A | | |
// | +--+----+ = | +----+
// +----+--+ | +----+ |
// | B | | |
// | | | |
// +-------+ +-------+
//
public CSG union(CSG csg)
{
CSGNode a = new CSGNode(this.clone().polygons);
CSGNode b = new CSGNode(csg.clone().polygons);
a.clipTo(b);
b.clipTo(a);
b.invert();
b.clipTo(a);
b.invert();
List <CSGPolygon> result = a.allPolygons();
result.AddRange(b.allPolygons());
return(CSG.fromPolygons(result));
}
// Convert solid space to empty space and empty space to solid space.
public void invert()
{
for (int i = 0; i < polygons.Count; i++)
{
polygons[i].flip();
}
plane.flip();
if (front != null)
{
front.invert();
}
if (back != null)
{
back.invert();
}
CSGNode temp = front;
front = back;
back = temp;
}