/// <summary>
/// Initializes a new instance of the <see cref="SDL2StreamWrapper"/> class.
/// </summary>
/// <param name="stream">The stream which will be wrapped by this object.</param>
public SDL2StreamWrapper(Stream stream)
{
Contract.Require(stream, nameof(stream));
this.stream = stream;
this.gchandle = GCHandle.Alloc(this, GCHandleType.Weak);
this.rwops = (SDL_RWops *)SDL.AllocRW();
this.rwops->size = Marshal.GetFunctionPointerForDelegate(new RWops_size(RWops_size_callback));
this.rwops->seek = Marshal.GetFunctionPointerForDelegate(new RWops_seek(RWops_seek_callback));
this.rwops->read = Marshal.GetFunctionPointerForDelegate(new RWops_read(RWops_read_callback));
this.rwops->write = Marshal.GetFunctionPointerForDelegate(new RWops_write(RWops_write_callback));
this.rwops->close = Marshal.GetFunctionPointerForDelegate(new RWops_close(RWops_close_callback));
this.rwops->data1 = GCHandle.ToIntPtr(gchandle);
}