/// <summary>
/// result * other ~= Proj(this onto other)
/// </summary>
/// <param name="other"></param>
/// <returns></returns>
[Pure] public double ProjectOntoComponentD(IntVector2 other)
{
return(other.Dot(this) / (double)other.SquaredNorm2());
}
public bool Equals(IntVector2 other) => X == other.X && Y == other.Y;
[Pure] public long Dot(IntVector2 other) => (long)X * other.X + (long)Y * other.Y;
[Pure] public IntVector2 To(IntVector2 other) => other - this;
public bool Contains(ref IntVector2 q) => Contains(First, Second, q);
public static bool Contains(IntVector2 p1, IntVector2 p2, IntVector2 q) => Contains(ref p1, ref p2, ref q);
public bool Contains(IntVector2 q) => Contains(ref q);
public static IntLineSegment2 Create(IntVector2 first, IntVector2 second)
{
return(new IntLineSegment2(first, second));
}
public void Deconstruct(out IntVector2 first, out IntVector2 second)
{
first = First;
second = Second;
}
/// <summary>
/// Note: Containment definition varies by hole vs terrain: Containment for holes
/// does not include the hole edge, containment for terrain includes the terrain edge.
/// This is important, else e.g. knockback + terrain push placing an entity on an edge
/// would potentially infinite loop.
/// </summary>
public static void PickDeepestPolynodeGivenHoleShapePolytree(this PolyTree polyTree, IntVector2 query, out PolyNode result, out bool isHole)
{
polyTree.AssertIsContourlessRootHolePunchResult();
PolyNode current = polyTree;
while (true)
{
// current is a hole of a hole's shape
PolyNode match;
// if we fail to find the first child land node border-inclusively containing the query point
if (!current.Childs.TryFindFirst(child => Clipper.PointInPolygon(new IntVector2(query.X, query.Y), child.Contour) == PolygonContainmentResult.InPolygon, out match))
{
result = current;
isHole = true;
return;
}
// next off, current is land of a hole's shape
current = match;
// If we fail to find a child hole border-excludingly containing the query point
if (!current.Childs.TryFindFirst(child => Clipper.PointInPolygon(new IntVector2(query.X, query.Y), child.Contour) != PolygonContainmentResult.OutsidePolygon, out match))
{
result = current;
isHole = false;
return;
}
// next off, current is a hole of a hole's shape
current = match;
}
}
public static bool PointInPolytree(this PolyTree polyTree, IntVector2 query, out PolyNode deepestPolyNode)
{
PickDeepestPolynodeGivenHoleShapePolytree(polyTree, query, out deepestPolyNode, out var isHole);
return(!isHole);
}
