高速碰撞盒穿过薄墙：接触时刻必须沿整段位移求解

public readonly record struct V(double X, double Y);
public readonly record struct Box(V Min, V Max);
public readonly record struct Contact(string Kind, double Time, V Normal);

public static class SweepAabb
{
    public static Contact Cast(Box moving, V delta, Box target)
    {
        Validate(moving);
        Validate(target);
        if (!double.IsFinite(delta.X) || !double.IsFinite(delta.Y))
            throw new ArgumentException("Displacement must be finite.");
        if (moving.Min.X < target.Max.X && moving.Max.X > target.Min.X
            && moving.Min.Y < target.Max.Y && moving.Max.Y > target.Min.Y)
            return new("Overlap", 0, default);
        double enter = double.NegativeInfinity, exit = double.PositiveInfinity;
        V normal = default;
        if (!Axis(moving.Min.X, moving.Max.X, target.Min.X, target.Max.X,
                  delta.X, new V(-1, 0), ref enter, ref exit, ref normal)
            || !Axis(moving.Min.Y, moving.Max.Y, target.Min.Y, target.Max.Y,
                     delta.Y, new V(0, -1), ref enter, ref exit, ref normal)
            || enter < 0 || enter > 1 || enter >= exit)
            return new("Miss", 1, default);
        return new("Hit", enter, normal);
    }

    private static bool Axis(double lo, double hi, double wallLo,
        double wallHi, double d, V negativeNormal,
        ref double enter, ref double exit, ref V normal)
    {
        // 平行时要求严格重叠，沿边滑动不作为阻挡。
        if (d == 0) return lo < wallHi && hi > wallLo;
        double near = (wallLo - hi) / d, far = (wallHi - lo) / d;
        V n = negativeNormal;
        if (near > far)
        {
            (near, far) = (far, near);
            n = new(-n.X, -n.Y);
        }
        // 相同进入时刻固定选 X 轴，避免角点法线不确定。
        if (near > enter) { enter = near; normal = n; }
        exit = Math.Min(exit, far);
        return enter < exit;
    }

    private static void Validate(Box b)
    {
        if (!double.IsFinite(b.Min.X) || !double.IsFinite(b.Min.Y)
            || !double.IsFinite(b.Max.X) || !double.IsFinite(b.Max.Y)
            || b.Min.X >= b.Max.X || b.Min.Y >= b.Max.Y)
            throw new ArgumentException("Box must have finite positive extents.");
    }
}

$ dotnet build SweepAabbLab.csproj -c Release --nologo -p:NuGetAudit=false
exitCode=0 warnings=0 errors=0
$ dotnet run --project SweepAabbLab.csproj -c Release --no-build --no-restore
exitCode=0
passed=17 failed=0 skipped=0 elapsedMs=19.7313
samples=5600
endOverlap=false
kind=Hit time=0.35 contactCenter=(3.5,0) normal=(-1,0)