|
- 临界多边形套料算法是一种用于解决多材料切割问题的经典算法。以下是一个简单的C++实现:
- ```cpp
- #include <iostream>
- #include <vector>
- #include <algorithm>
- using namespace std;
- struct Point {
- double x, y;
- };
- double cross(const Point& a, const Point& b, const Point& c) {
- return (b.x - a.x) * (c.y - a.y) - (b.y - a.y) * (c.x - a.x);
- }
- bool cmp(const Point& a, const Point& b) {
- return a.x < b.x || (a.x == b.x && a.y < b.y);
- }
- void convexHull(vector<Point>& points, vector<Point>& hull) {
- int n = points.size();
- sort(points.begin(), points.end(), cmp);
- int k = 0;
- for (int i = 0; i < n; ++i) {
- while (k >= 2 && cross(hull[k - 2], hull[k - 1], points[i]) <= 0) k--;
- hull[k++] = points[i];
- }
- for (int i = n - 2, t = k + 1; i >= 0; --i) {
- while (k >= t && cross(hull[k - 2], hull[k - 1], points[i]) <= 0) k--;
- hull[k++] = points[i];
- }
- hull.resize(k - 1);
- }
- vector<vector<Point>> cut(const vector<Point>& material, const vector<Point>& pattern) {
- vector<vector<Point>> result;
- vector<Point> hull;
- convexHull(material, hull);
- int m = hull.size();
- for (int i = 0; i < m; ++i) {
- int j = (i + 1) % m;
- if (cross(pattern[0], pattern[1], hull[i]) > 0) {
- vector<Point> polygon;
- polygon.push采用back(pattern[0]);
- polygon.push采用back(pattern[1]);
- polygon.push采用back(hull[j]);
- result.push采用back(polygon);
- } else if (cross(pattern[0], pattern[1], hull[i]) < 0) {
- vector<Point> polygon;
- polygon.push采用back(pattern[0]);
- polygon.push采用back(pattern[1]);
- polygon.push采用back(hull[i]);
- result.push采用back(polygon);
- } else {
- if (cross(pattern[0], pattern[1], hull[j]) > 0) {
- vector<Point> polygon;
- polygon.push采用back(pattern[0]);
- polygon.push采用back(pattern[1]);
- polygon.push采用back(hull[i]);
- result.push采用back(polygon);
- } else if (cross(pattern[0], pattern[1], hull[j]) < 0) {
- vector<Point> polygon;
- polygon.push采用back(pattern[0]);
- polygon.push采用back(pattern[1]);
- polygon.push采用back(hull[j]);
- result.push采用back(polygon);
- } else {
- if (cross(pattern[0], pattern[1], hull[i]) > 0) {
- vector<Point> polygon;
- polygon.push采用back(pattern[0]);
- polygon.push采用back(pattern[1]);
- polygon.push采用back(hull[j]);
- result.push采用back(polygon);
- } else if (cross(pattern[0], pattern[1], hull[i]) < 0) {
- vector<Point> polygon;
- polygon.push采用back(pattern[0]);
- polygon.push采用back(pattern[1]);
- polygon.push采用back(hull[i]);
- result.push采用back(polygon);
- } else {
- vector<Point> polygon;
- polygon.push采用back(pattern[0]);
- polygon.push采用back(pattern[1]);
- polygon.push采用back(hull[i]);
- polygon.push采用back(hull[j]);
- result.push采用back(polygon);
- }
- }
- }
- }
- return result;
- }
- int main() {
- vector<Point> material = {{0, 0}, {4, 0}, {4, 4}, {0, 4}};
- vector<Point> pattern = {{1, 1}, {3, 1}};
- vector<vector<Point>> result = cut(material, pattern);
- for (const auto& polygon : result) {
- for (const auto& point : polygon) {
- cout << "(" << point.x << ", " << point.y << ") ";
- }
- cout << endl;
- }
- return 0;
- }
- ```
- 这个程序首先定义了一个点的结构体,然后实现了一个求凸包的函数`convexHull`,接着实现了一个求解临界多边形套料问题的函数`cut`。最后在`main`函数中测试了这个算法。
复制代码 |
|