第一个多边形

void GLWidget::paintGL(){    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);    glLoadIdentity();    glTranslatef(-1.5,0.0,-6.0);    glColor3f(1,0,0);    glBegin(GL_TRIANGLES);    glVertex3f(0,1.0,0.0);    glVertex3f(-1.0,-1.0,0.0);    glVertex3f(1.0,-1.0,0.0);    glEnd();    glTranslatef(3.0,0.0,0.0);    glBegin(GL_QUADS);    glVertex3f(-1.0,1.0,0.0);    glVertex3f(1.0,1.0,0.0);    glVertex3f(1.0,-1.0,0.0);    glVertex3f(-1.0,-1.0,0.0);    glEnd();}

参考资料：OpenGL教程