在OpenGL ES(iPhone)中绘制到屏幕外渲染缓冲区

// 创建纹理对象
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);

// 将纹理对象作为渲染目标
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture, 0);

// 绘制图形
glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT);

// 将纹理对象绑定到屏幕上的矩形上
glBindTexture(GL_TEXTURE_2D, texture);
glEnable(GL_TEXTURE_2D);
glBegin(GL_QUADS);
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 0.0f);
glTexCoord2f(1.0f, 0.0f); glVertex3f(1.0f, -1.0f, 0.0f);
glTexCoord2f(1.0f, 1.0f); glVertex3f(1.0f, 1.0f, 0.0f);
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 0.0f);
glEnd();