//////////////////////////////////////////////////////////////////////////
//if ( !_check() )
// return;

//rendering bezier cells...
system("CLS");
for (int i=0; i {
int pos = i * 3;
if ( (pos+3) < vertexNum )
renderBezierCell( BezierCell(pos, pos+1, pos+2, pos+3) );
}
//////////////////////////////////////////////////////////////////////////
}

// 3次bezier曲线经过vetex0和vextex3
void renderBezierCell(const BezierCell& cell)
{
double *pBuffer = new double[Bezier3CtrlPnt * 3];

cout << "----------------------------------------------------" << endl;

cout << "Vertex number : " << vertexNum << endl;
cout << "Cell number : " << cellNum << endl;
cout << "The render cell: " << cell[0] << " " << cell[1] << " " << cell[2] << " " << cell[3] << endl;

for (int i = 0, bg = 0; i<4; i++)
{
Vec3d v = vertexVector[ cell[i] ];
pBuffer[bg++] = v.x();
pBuffer[bg++] = v.y();
pBuffer[bg++] = v.z();

cout << v.x() << " " << v.y() << " " << v.z() << endl;
}cout << "----------------------------------------------------" << endl;

glMap1d(GL_MAP1_VERTEX_3, 0.0, 1.0, 3, Bezier3CtrlPnt, pBuffer);
glBegin(GL_LINE_STRIP);
{
for (int i = 0; i <= 30; i++)
gleva lCoord1f((GLfloat) i/30.0f);
} glEnd();

delete pBuffer; pBuffer = 0;
}

void clear()
{
cellNum = 0;
vertexNum = 0;

isFirstRender = true;

vertexVector.clear();
}
protected:
bool _check() { vertexNum =vertexVector.size();
return vertexNum == (cellNum - 1) * 3 + 4; }
void _updateVertexNum() { vertexNum=vertexVector.size();}

int cellNum; //单元个数
int vertexNum; //顶点个数

bool isFirstRender; //首次标志
std::vector vertexVector; //顶点数组

class cellRenderImple
{
public:
enum RenderStep
{
Push = 0,
Change = 1
};
cellRenderImple(){ setPush(); }
bool operator()(void) { return flag; }
void setPush() { flag = Push; }
void setChange() { flag = Change; }

RenderStep flag; //cell的渲染状态
} cellRenderState;
};

测试程序如下：

#include
#include
#include

#include "BezierCurve.h"

using namespace std;

enum WindowSize{
WinWidth = 1024,
WinHeight = 768
};

int g_Viewport[4];
double g_ModelMatrix[16];
double g_ProjMatrix[16];
BezierCurve myBezier;

//////////////////////////////////////////////////////////////////////////
void init();
void display();
void reshape(int w, int h);
void keyboard(unsigned char key, int x, int y);
void mouse(int button, int state, int x, int y);
void motion(int x, int y);

int main(int argc, char** argv)
{
glutInit(&argc, argv);
glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB);
glutInitWindowSize (WinWidth, WinHeight);
glutInitWindowPosition (100, 100);
glutCreateWindow (argv[0]);

init ();
glutDisplayFunc(display);
glutReshapeFunc(reshape);
glutKeyboardFunc (keyboard);
glutMouseFunc(mouse);
glutMotionFunc(motion);

glutMainLoop();

return 0;
}

void init(void)
{
glClearColor(0.0, 0.0, 0.0, 0.0);
glShadeModel(GL_SMOOTH);

myBezier.begin();
}

void display(void)
{
glClear(GL_COLOR_BUFFER_BIT);

glColor3f(1.0, 1.0, 0.0);
glPointSize(5.0);

glPushMatrix();
{
myBezier.renderCurve();
}glPopMatrix();

glutSwapBuffers();
}

void reshape(int w, int h)
{
glViewport(0, 0, (GLsizei) w, (GLsizei) h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
if (w <= h)
glOrtho(-5.0, 5.0, -5.0*(GLfloat)h/(GLfloat)w,
5.0*(GLfloat)h/(GLfloat)w, -5.0, 5.0);
else
glOrtho(-5.0*(GLfloat)w/(GLfloat)h,
5.0*(GLfloat)w/(GLfloat)h, -5.0, 5.0, -5.0, 5.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}

void keyboard(unsigned char key, int x, int y)
{
switch (key) {
case 27:
exit(0);
break;
}
}

void mouse(int button, int state, int x, int y)
{
double vertex[3];