public GLRenderBuffer(int format, int width, int height, int fsaa)
: base(width, height, 1, GLPixelUtil.GetClosestPixelFormat(format), BufferUsage.WriteOnly)
{
GLFormat = format;
/// Generate renderbuffer
Gl.glGenRenderbuffersEXT(1, out this._renderBufferId);
/// Bind it to FBO
Gl.glBindRenderbufferEXT(Gl.GL_RENDERBUFFER_EXT, this._renderBufferId);
/// Allocate storage for depth buffer
Gl.glRenderbufferStorageEXT(Gl.GL_RENDERBUFFER_EXT, format, width, height);
}