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MoonTools.Bonk
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even better gc optimization

generics
Evan Hemsley 2019-10-25 12:37:25 -07:00
parent 2a715e71db
commit 20872021fc
2 changed files with 104 additions and 22 deletions
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11
Bonk/EPA2D.cs
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@ -22,15 +22,14 @@ namespace MoonTools.Core.Bonk
public static class EPA2D
{
// vector returned gives direction from A to B
public static Vector2 Intersect(IShape2D shapeA, Transform2D Transform2DA, IShape2D shapeB, Transform2D Transform2DB, (Func<Vector2, Vector2>, Vector2, Vector2) givenSimplexVertices)
public static Vector2 Intersect(IShape2D shapeA, Transform2D Transform2DA, IShape2D shapeB, Transform2D Transform2DB, Simplex givenSimplex)
{
var simplexVertices = new SimplexVertices(new Vector2?[36]);
var (simplexSupport, a, b) = givenSimplexVertices;
simplexVertices.Add(simplexSupport(a));
simplexVertices.Add(simplexSupport(b));
simplexVertices.Add(simplexSupport(-a));
simplexVertices.Add(simplexSupport(-b));
foreach (var vertex in givenSimplex.Vertices)
{
simplexVertices.Add(vertex);
}
var e0 = (simplexVertices[1].X - simplexVertices[0].X) * (simplexVertices[1].Y + simplexVertices[0].Y);
var e1 = (simplexVertices[2].X - simplexVertices[1].X) * (simplexVertices[2].Y + simplexVertices[1].Y);

115
Bonk/GJK2D.cs
View File

@ -2,43 +2,126 @@
using MoonTools.Core.Structs;
using System;
using MoonTools.Core.Bonk.Extensions;
using System.Collections.Generic;
namespace MoonTools.Core.Bonk
{
// TODO: get rid of minkowski closure for GC purposes
public struct MinkowskiDifference : IEquatable<MinkowskiDifference>
{
private IShape2D shapeA;
private Transform2D transformA;
private IShape2D shapeB;
private Transform2D transformB;
public MinkowskiDifference(IShape2D shapeA, Transform2D transformA, IShape2D shapeB, Transform2D transformB)
{
this.shapeA = shapeA;
this.transformA = transformA;
this.shapeB = shapeB;
this.transformB = transformB;
}
public bool Equals(MinkowskiDifference other)
{
return
shapeA == other.shapeA &&
transformA.Equals(other.transformA) &&
shapeB == other.shapeB &&
transformB.Equals(other.transformB);
}
public Vector2 Support(Vector2 direction)
{
return shapeA.Support(direction, transformA) - shapeB.Support(-direction, transformB);
}
}
public struct Simplex : IShape2D
{
MinkowskiDifference minkowskiDifference;
Vector2 directionA;
Vector2 directionB;
public Simplex(MinkowskiDifference minkowskiDifference, Vector2 directionA, Vector2 directionB)
{
this.minkowskiDifference = minkowskiDifference;
this.directionA = directionA;
this.directionB = directionB;
}
public IEnumerable<Position2D> Vertices
{
get
{
yield return (Position2D)Support(directionA);
yield return (Position2D)Support(directionB);
yield return (Position2D)Support(-(directionB - directionA).Perpendicular());
}
}
public AABB AABB(Transform2D transform)
{
return Bonk.AABB.FromTransformedVertices(Vertices, transform);
}
public bool Equals(IShape2D other)
{
if (other is Simplex polytope)
{
return minkowskiDifference.Equals(polytope.minkowskiDifference) &&
directionA == polytope.directionA &&
directionB == polytope.directionB;
}
return false;
}
public Vector2 Support(Vector2 direction)
{
return minkowskiDifference.Support(direction);
}
public Vector2 Support(Vector2 direction, Transform2D transform)
{
return Vector2.Transform(Support(direction), transform.TransformMatrix);
}
}
public static class GJK2D
{
public static bool TestCollision(IShape2D shapeA, Transform2D transformA, IShape2D shapeB, Transform2D transformB)
{
return OriginInside(MinkowskiDifference(shapeA, transformA, shapeB, transformB));
var minkowskiDifference = new MinkowskiDifference(shapeA, transformA, shapeB, transformB);
return OriginInside(minkowskiDifference);
}
public static (bool, (Func<Vector2, Vector2>, Vector2, Vector2)) CollisionAndSimplex(IShape2D shapeA, Transform2D transformA, IShape2D shapeB, Transform2D transformB)
public static (bool, Simplex) CollisionAndSimplex(IShape2D shapeA, Transform2D transformA, IShape2D shapeB, Transform2D transformB)
{
var support = MinkowskiDifference(shapeA, transformA, shapeB, transformB);
var result = OriginInsideWithSimplex(support);
return (result.Item1, (support, result.Item2, result.Item3));
var minkowskiDifference = new MinkowskiDifference(shapeA, transformA, shapeB, transformB);
var (collision, a, b) = OriginInsideWithSimplex(minkowskiDifference);
var polytope = new Simplex(minkowskiDifference, a, b);
return (collision, polytope);
}
private static Func<Vector2, Vector2> MinkowskiDifference(IShape2D shapeA, Transform2D transformA, IShape2D shapeB, Transform2D transformB)
private static Vector2 MinkowskiDifference(Vector2 direction, IShape2D shapeA, Transform2D transformA, IShape2D shapeB, Transform2D transformB)
{
return direction => shapeA.Support(direction, transformA) - shapeB.Support(-direction, transformB);
return shapeA.Support(direction, transformA) - shapeB.Support(-direction, transformB);
}
private static bool OriginInside(Func<Vector2, Vector2> support)
private static bool OriginInside(MinkowskiDifference minkowskiDifference)
{
var a = support(Vector2.UnitX);
var b = support(-a);
var a = minkowskiDifference.Support(Vector2.UnitX);
var b = minkowskiDifference.Support(-a);
return Vector2.Dot(a, b) > 0 ? false : CheckSimplex(support, a, b);
return Vector2.Dot(a, b) > 0 ? false : CheckSimplex(minkowskiDifference.Support, a, b);
}
private static (bool, Vector2, Vector2) OriginInsideWithSimplex(Func<Vector2, Vector2> support)
private static (bool, Vector2, Vector2) OriginInsideWithSimplex(MinkowskiDifference minkowskiDifference)
{
var a = support(Vector2.UnitX);
var b = support(-a);
var a = minkowskiDifference.Support(Vector2.UnitX);
var b = minkowskiDifference.Support(-a);
return Vector2.Dot(a, b) > 0 ? (false, a, b) : Simplex(support, a, b);
return Vector2.Dot(a, b) > 0 ? (false, a, b) : Simplex(minkowskiDifference.Support, a, b);
}
private static bool CheckSimplex(Func<Vector2, Vector2> support, Vector2 a, Vector2 b)