版权声明:欢迎转载,请注明出处噢,谢谢 https://blog.csdn.net/DT2131/article/details/78948132
二次插值样条曲线补首尾的画法
N 为点数+2,虚拟首尾
DIV 代表曲线细分的程度
使用了 EasyX 图形库,感谢 EasyX 团队
#include <bits/stdc++.h>
#include <graphics.h>
#include <conio.h>
using namespace std;
typedef struct Node {
int x, y;
}Node;
const int N = 8 + 2;
const int DIV = 50000;
Node nodes[N];
void input() {
nodes[1] = { 100,100 };
nodes[2] = { 140,160 };
nodes[3] = { 180,200 };
nodes[4] = { 220,220 };
nodes[5] = { 260,270 };
nodes[6] = { 300,300 };
nodes[7] = { 340,320 };
nodes[8] = { 370,370 };
nodes[0] = nodes[1];
nodes[9] = nodes[8];
for (int i = 0; i < N; i++)
putpixel(nodes[i].x, nodes[i].y, RED);
}
void interpolation() {
int x, y;
double t, dt = 0.5 / DIV;
for (int i = 0; i < N - 3; i++) {
for (t = 0; t <= 0.5; t += dt) {
x = (-4 * t*t*t + 4 * t*t - t)*nodes[i].x + (12 * t*t*t - 10 * t*t + 1)*nodes[i + 1].x + (-12 * t*t*t + 8 * t*t + t)*nodes[i + 2].x + (4 * t*t*t - 2 * t*t)*nodes[i + 3].x;
y = (-4 * t*t*t + 4 * t*t - t)*nodes[i].y + (12 * t*t*t - 10 * t*t + 1)*nodes[i + 1].y + (-12 * t*t*t + 8 * t*t + t)*nodes[i + 2].y + (4 * t*t*t - 2 * t*t)*nodes[i + 3].y;
putpixel(x, y, WHITE);
}
}
}
int main()
{
initgraph(640, 480);
input();
interpolation();
system("pause");
return 0;
}