OpenGL--Bezier曲线

来源：互联网发布：java编程大赛题目编辑：程序博客网时间：2024/05/23 14:35

关于Bezier曲线，相信所有接触过的都知道Q(t) = Pi *Cnk * (1-t)^(n-k) * t^k;（i = 0,1,2,3......n)

这里我们把Cnk * (1-t)^(n-k) * t^k当做调和函数（blendFcn) 其实所谓 blendFcn有点像数学中的权值，对于控制点，每个点都有一个权值比重，并由此比重与点的乘积和获得目标点的坐标，这个就是Bezier曲线的关键所在————————在此感谢学工老师的指导

#include "GL/glut.h"#include "stdio.h"/************************************************************************//* POINT_DENSITY PER 0-1                                              *//************************************************************************/#define POINT_DENSITY 100/************************************************************************//* here C = new GLfloat[n+1];                                           *//************************************************************************/struct P{GLfloat x, y, z;};void countCnk(GLint *C, GLint n){int i = 0;C[0] = 1;for(int k = 1; k <= n; k++){C[k] = C[k-1] * (n - k + 1)/k;}// for checkingfor(i = 0; i <= n; i++){printf("%3d", i);}printf("\n");for(i = 0; i <= n; i++){printf("%3d", C[i]);}printf("\n");}/************************************************************************//* HERE WE MAKE THE Z == pList.z WITHOUT CARING ABOUT THE BLENDARGS     *//************************************************************************/void countQt(GLint n, P* pList, GLint*C, GLfloat t, P *result){GLfloat blendArgs;result->x = result->y = result->z = 0;for(int k = 0; k <= n; k++){blendArgs = C[k] * pow(t, k) * pow(1-t, n-k);result->x += pList[k].x * blendArgs;result->y += pList[k].y * blendArgs;//result->z += pList[k].z * blendArgs;result->z = pList[k].z;}}void drawBezier(P *pList, int n){GLint *C = new GLint[n+1];P tempResult;GLfloat t;countCnk(C, n);glBegin(GL_LINE_STRIP);for(int i = 0; i < POINT_DENSITY; i++){t = GLfloat(i)/POINT_DENSITY;printf("drawing the t%1.2f\n", t);countQt(n, pList, C, t, &tempResult);glVertex3f(tempResult.x, tempResult.y, tempResult.z);}glEnd();}