using System;
using System.Collections.Generic;
using System.Numerics;
using MoonTools.Core.Structs;
namespace MoonTools.Core.Bonk
{
///
/// A rectangle is a shape defined by a minimum and maximum X value and a minimum and maximum Y value.
///
public struct Rectangle : IShape2D, IEquatable
{
public int MinX { get; }
public int MinY { get; }
public int MaxX { get; }
public int MaxY { get; }
public AABB AABB { get; }
public IEnumerable Vertices
{
get
{
yield return new Position2D(MinX, MinY);
yield return new Position2D(MinX, MaxY);
yield return new Position2D(MaxX, MinY);
yield return new Position2D(MaxX, MaxY);
}
}
public Rectangle(int minX, int minY, int maxX, int maxY)
{
MinX = minX;
MinY = minY;
MaxX = maxX;
MaxY = maxY;
AABB = new AABB(minX, minY, maxX, maxY);
}
public Vector2 Support(Vector2 direction, Transform2D transform)
{
var maxDotProduct = float.NegativeInfinity;
var maxVertex = new Vector2(MinX, MinY);
foreach (var vertex in Vertices)
{
var transformed = Vector2.Transform(vertex, transform.TransformMatrix);
var dot = Vector2.Dot(transformed, direction);
if (dot > maxDotProduct)
{
maxVertex = transformed;
maxDotProduct = dot;
}
}
return maxVertex;
}
public AABB TransformedAABB(Transform2D transform)
{
return AABB.Transformed(AABB, transform);
}
public override bool Equals(object obj)
{
return obj is IShape2D other && Equals(other);
}
public bool Equals(IShape2D other)
{
return (other is Rectangle rectangle && Equals(rectangle)) || (other is Polygon polygon && Equals(polygon));
}
public bool Equals(Rectangle other)
{
return MinX == other.MinX &&
MinY == other.MinY &&
MaxX == other.MaxX &&
MaxY == other.MaxY;
}
public bool Equals(Polygon other)
{
return RectanglePolygonComparison.Equals(other, this);
}
public override int GetHashCode()
{
return HashCode.Combine(MinX, MinY, MaxX, MaxY);
}
public static bool operator ==(Rectangle a, Rectangle b)
{
return a.Equals(b);
}
public static bool operator !=(Rectangle a, Rectangle b)
{
return !(a == b);
}
}
}