OpenGL绘制绿色网状圆柱 c++

下面是使用OpenGL绘制绿色网状圆柱的C++代码：

#include <GL/glut.h>
#include <cmath>

const int N = 50; // 网格数量
const float PI = 3.1415926f; // 圆周率

void drawCylinder() {
  glColor3f(0.0f, 1.0f, 0.0f); // 绿色
  glBegin(GL_QUAD_STRIP);
  for (int i = 0; i <= N; ++i) {
    float angle = 2 * PI / N * i;
    float x = cos(angle);
    float y = sin(angle);
    glVertex3f(x, y, -1.0f);
    glVertex3f(x, y, 1.0f);
  }
  glEnd();

  glColor3f(0.0f, 0.0f, 0.0f); // 黑色
  glBegin(GL_LINES);
  for (int i = 0; i <= N; ++i) {
    float angle = 2 * PI / N * i;
    float x = cos(angle);
    float y = sin(angle);
    glVertex3f(x, y, -1.0f);
    glVertex3f(x, y, 1.0f);
  }
  glEnd();

  glBegin(GL_POLYGON);
  for (int i = 0; i <= N; ++i) {
    float angle = 2 * PI / N * i;
    float x = cos(angle);
    float y = sin(angle);
    glVertex3f(x, y, -1.0f);
  }
  glEnd();

  glBegin(GL_POLYGON);
  for (int i = 0; i <= N; ++i) {
    float angle = 2 * PI / N * i;
    float x = cos(angle);
    float y = sin(angle);
    glVertex3f(x, y, 1.0f);
  }
  glEnd();
}

void display() {
  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
  gluLookAt(2.0f, 2.0f, 2.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f);
  drawCylinder();
  glutSwapBuffers();
}

void reshape(int width, int height) {
  glViewport(0, 0, width, height);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  gluPerspective(60.0f, (float)width / height, 0.1f, 100.0f);
}

int main(int argc, char *argv[]) {
  glutInit(&argc, argv);
  glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH);
  glutInitWindowSize(800, 600);
  glutCreateWindow("Cylinder");
  glutDisplayFunc(display);
  glutReshapeFunc(reshape);
  glEnable(GL_DEPTH_TEST);
  glutMainLoop();
  return 0;
}

该程序使用OpenGL库绘制一个绿色的网状圆柱，并使用GLUT库管理窗口和事件。具体实现采用了三个步骤：首先绘制圆柱侧面的网格，然后绘制网格线，最后绘制圆柱两端的多边形。其中，使用GL_QUAD_STRIP绘制圆柱侧面的网格，使用GL_LINES绘制网格线，使用GL_POLYGON绘制圆柱两端的多边形。