OPENGL3_基本图元

类型	说明
GL_POINTS	单个顶点集
GL_LINES	多组双顶点线段
GL_POLYGON	单个简单填充凸多边形
GL_TRAINGLES	多组独立填充三角形
GL_QUADS	多组独立填充四边形
GL_LINE_STRIP	不闭合折线
GL_LINE_LOOP	闭合折线
GL_TRAINGLE_STRIP	线型连续填充三角形串
GL_TRAINGLE_FAN	扇形连续填充三角形串
GL_QUAD_STRIP	连续填充四边形串

　　　　　　　　　　　　　　　　　　几何图元类型说明

代码效果

代码

int DrawGLScene(GLvoid)									// Here's Where We Do All The Drawing
{
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);	// Clear Screen And Depth Buffer
	glLoadIdentity();									// Reset The Current Modelview Matrix

	//移动是相对当前位置移动（第一次移动相对与屏幕中心0，0，0下一次再移动时相对的就是本次移动后的位置了）
	//向屏幕内移动18.9个单位，这样1个单位（1米）对应480/(2*tan(22.5)*(18.9+0.1)= 30像素
	glTranslatef(0.0f,0.0f,-18.9f);

	// 绘制不连续线段，把屏幕分成9部分
	glBegin(GL_LINES);
	// 横线
	glVertex3f( -21.0f, 3.0f, 0.0f);
	glVertex3f(21.0f, 3.0f, 0.0f);
	glVertex3f( -21.0f, -3.0f, 0.0f);
	glVertex3f( 21.0f, -3.0f, 0.0f);
	// 竖线
	glVertex3f( -3.0f, 8.0f, 0.0f);
	glVertex3f(-3.0f, -8.0f, 0.0f);
	glVertex3f( 3.0f, 8.0f, 0.0f);
	glVertex3f( 3.0f, -8.0f, 0.0f);
	glEnd();

	// 绘制点
	glBegin(GL_POINTS);
	glColor3f(1.0f,0.0f,0.0f);// 设置当前色为红色
	glVertex3f( -8.0f, 5.5f, 0.0f);
	glVertex3f( -7.5f, 5.5f, 0.0f);
	glVertex3f( -7.0f, 5.5f, 0.0f);
	glEnd();

	// 绘制不闭合折线
	glBegin(GL_LINE_STRIP);
	glColor3f(1.0f,1.0f,0.0f);// 设置当前色为黄色
	glVertex3f( -2.0f, 5.5f, 0.0f);
	glVertex3f( 2.0f, 5.5f, 0.0f);
	glVertex3f( -2.0f, 4.0f, 0.0f);
	glVertex3f( 2.0f, 4.0f, 0.0f);
	glEnd();

	// 绘制闭合折线
	glBegin(GL_LINE_LOOP);
	glColor3f(0.0f,0.0f,1.0f);// 设置当前色为蓝色
	glVertex3f( 6.0f, 6.0f, 0.0f);
	glVertex3f( 4.0f, 4.0f, 0.0f);
	glVertex3f( 8.0f, 4.0f, 0.0f);
	glEnd();

	// 绘制多组独立填充三角形（以下绘制2个三角形）
	glBegin(GL_TRIANGLES);
	glColor3f(1.0f,0.0f,0.0f);// 设置当前色为红色
	glVertex3f( -9.0f, 1.0f, 0.0f);
	glVertex3f(-8.0f,-1.0f, 0.0f);
	glVertex3f( -10.0f,-1.0f, 0.0f);

	glVertex3f( -6.0f, 1.0f, 0.0f);
	glVertex3f(-5.0f,-1.0f, 0.0f);
	glVertex3f( -7.0f,-1.0f, 0.0f);
	glEnd();

	// 绘制三角形带
	glBegin(GL_TRIANGLE_STRIP);//(以下绘制3个连续三角形)

	//第一个三角形由点123逆时针构成
	//第二个三角形由点324逆时针构成
	//第三个三角形由点345逆时针构成

	glColor3f(1.0f,0.0f,0.0f);// 设置当前色为红色
	glVertex3f( -2.0f,-1.0f, 0.0f);//点1
	glVertex3f(0.0f,-1.0f, 0.0f);//点2
	glVertex3f( -1.0f, 1.0f, 0.0f);//点3
	glColor3f(0.0f,1.0f,0.0f);// 设置当前色为绿色
	glVertex3f( 1.0f,1.0f, 0.0f);//点4
	glColor3f(0.0f,0.0f,1.0f);// 设置当前色为蓝色
	glVertex3f(2.5f,2.5f, 0.0f);//点5

	glEnd();

	return TRUE;										// Everything Went OK
}