Opengl第一个小例子

#include <GL/glut.h>

void init(void)
{
 glClearColor(1.0, 1.0, 1.0, 0.0);
 glMatrixMode(GL_PROJECTION);
 gluOrtho2D(0.0, 200, 0.0, 150.0);
}

void lineSegment(void)
{
 glClear(GL_COLOR_BUFFER_BIT);

 glColor3f(1.0, 0.0, 0.0);
 glBegin(GL_LINES);
  glVertex2i(180, 15);
  glVertex2i(10, 145);
 glEnd();

 glFlush();
}

void main(int argc, char **argv)
{
 glutInit(&argc, argv);
 glutInitDisplayMode(GLUT_SINGLE | GLUT_RGBA);
 glutInitWindowPosition(200, 200);
 glutInitWindowSize(400, 300);
 glutCreateWindow("an example opengl program");

 init();
 glutDisplayFunc(lineSegment);
 glutMainLoop();

}