// Slice From Point
static public Slice2D SliceFromPoint(Polygon2D polygon, Vector2D point, float rotation)
{
Slice2D result = Slice2D.Create(null, point, rotation);
// Normalize into clockwise
polygon.Normalize();
Vector2D sliceA = new Vector2D(point);
Vector2D sliceB = new Vector2D(point);
sliceA.Push(rotation, 1e+10f / 2);
sliceB.Push(rotation, -1e+10f / 2);
if (polygon.PointInPoly(point) == false)
{
return(result);
}
// Getting the list of intersections
List <Vector2D> intersectionsA = polygon.GetListLineIntersectPoly(new Pair2D(point, sliceA));
List <Vector2D> intersectionsB = polygon.GetListLineIntersectPoly(new Pair2D(point, sliceB));
// Sorting intersections from one point
if (intersectionsA.Count > 0 && intersectionsB.Count > 0)
{
sliceA = Vector2DList.GetListSortedToPoint(intersectionsA, point) [0];
sliceB = Vector2DList.GetListSortedToPoint(intersectionsB, point) [0];
}
else
{
return(result);
}
List <Pair2D> collisionList = new List <Pair2D>();
collisionList.Add(new Pair2D(sliceA, sliceB));
result.AddPolygon(polygon);
foreach (Pair2D id in collisionList)
{
result.AddCollision(id.A);
result.AddCollision(id.B);
// Sclice line points generated from intersections list
Vector2D vec0 = new Vector2D(id.A);
Vector2D vec1 = new Vector2D(id.B);
double rot = Vector2D.Atan2(vec0, vec1);
// Slightly pushing slice line so it intersect in all cases
vec0.Push(rot, LinearSlicer.precision);
vec1.Push(rot, -LinearSlicer.precision);
// For each in polygons list attempt convex split
List <Polygon2D> temp = new List <Polygon2D>(result.GetPolygons()); // necessary?
foreach (Polygon2D poly in temp)
{
// NO, that's the problem
Slice2D resultList = LinearSlicer.Slice(poly, new Pair2D(vec0, vec1));
if (resultList.GetPolygons().Count > 0)
{
if (resultList.slices.Count > 0)
{
foreach (List <Vector2D> i in resultList.slices)
{
result.AddSlice(i);
}
}
foreach (Polygon2D i in resultList.GetPolygons())
{
result.AddPolygon(i);
}
// If it's possible to perform splice, remove parent polygon from result list
result.RemovePolygon(poly);
}
}
}
result.RemovePolygon(polygon);
return(result);
}
static public Slice2D LinearSlice(Polygon2D polygon, Pair2D slice)
{
return(LinearSlicer.Slice(polygon, slice));
}
