c# - 查找形状上的角/边（可以定义该形状的最小顶点）

Question

我正在尝试获得以下形状的角：

我所说的角落是指这个（红点）：

可以定义此形状的最小点数。

我已经实现了以下内容：

    public Shape Optimize()
    {
        // If the vertices are null or empty this can't be executed
        if (vertices.IsNullOrEmpty())
            return this; // In this case, return the same instance.

        if (!edges.IsNullOrEmpty())
            edges = null; //Reset edges, because a recalculation was requested

        // The corners available on each iteration
        var corners = new Point[] { Point.upperLeft, Point.upperRight, Point.downLeft, Point.downRight };

        //The idea is to know if any of the following or previous vertice is inside of the the array from upside, if it is true then we can add it.

        Point[] vs = vertices.ToArray();

        for (int i = 0; i < vertices.Count - 1; ++i)
        {
            Point backPos = i > 0 ? vs[i - 1] : vs[vertices.Count - 1],
                  curPos = vs[i], //Punto actual
                  nextPos = i < vertices.Count - 1 ? vs[i + 1] : vs[0];

            // We get the difference point between the actual point and the back & next point
            Point backDiff = backPos - curPos,
                  nextDiff = nextPos - curPos,
                  totalDiff = nextPos - backPos;

            if (corners.Contains(backDiff) || corners.Contains(nextDiff) || corners.Contains(totalDiff))
                AddEdge(curPos, center); // If any of the two points are defined in the corners of the point of before or after it means that the actual vertice is a edge/corner
        }

        return this;
    }

这适用于矩形形状，但旋转后的形状非常清晰，因此，此代码效果不佳：