OPENGL彩色圆环编程示例，本事例运用OpenGL绘制一圆环，其中包括GL_TRIANGLE_STRIP和glMaterialiv(GL_FRONT, GL_COLOR_INDEXES, colors[0].indexes)的使用．,Color Circle OPENGL programming examples, the examples of the use of OpenGL drawing a circle, including GL_TRIANGLE_STRIP and glMate