简单的四叉树的代码

比眉伴天荒 2024-03-25 15:02 4阅读 0赞

四叉树是一种用于管理二维空间中的对象的数据结构。它通过将二维空间划分成若干个较小的矩形区域(也称为节点)来帮助组织和管理对象。每个节点都有四个子节点，因此称之为四叉树。

以下是一个简单的四叉树代码的示例，使用 Python 语言编写:

\`\`\` class QuadTreeNode: def **init**(self, bounds, depth=0, max\_depth=5, max\_items=3): self.bounds = bounds self.depth = depth self.max\_depth = max\_depth self.max\_items = max\_items self.items = \[\] self.children = \[\]

def insert(self, item):
        if len(self.children) == 0:
            self.items.append(item)
    
            if len(self.items) > self.max_items and self.depth < self.max_depth:
                self.subdivide()
        else:
            index = self.get_index(item)
            if index != -1:
                self.children[index].insert(item)
            else:
                self.items.append(item)
    
    def get_index(self, item):
        x = item[0]
        y = item[1]
        left = self.bounds[0]
        top = self.bounds[1]
        right = self.bounds[2]
        bottom = self.bounds[3]
    
        if x < left or x > right or y < top or y > bottom:
            return -1
    
        mid_x = (left + right) / 2
        mid_y = (top + bottom) / 2
    
        if x < mid_x:
            if y < mid_y:
                return 0
            else:
                return 3
        else:
            if y < mid_y:
                return 1
            else:
                return 2
    
    def subdivide(self):
        left = self.bounds[0]
        top = self.bounds[1]
        right = self.bounds[2]
        bottom = self.bounds[3]
    
        mid_x = (left + right) / 2
        mid_y = (top + bottom) / 2
    
        self.children.append(QuadTreeNode((left, top, mid_x, mid_y), self.depth + 1, self.max_depth, self.max_items))
        self.children.append(Quad