这个程序demo了怎样使用glCopyToTexture函数绘制。这个纹理是应用在一个立方体上的。-This app demonstrates how to render to a texture using the glCopyToTexture function. I have used one of my old projects to create a interesting effect (Blending colors). This is rendered to a viewport and then copied to a texture. The texture is then applied to a cube.