If a function needs to maintain the state of some data over successive calls, such as a working buffer or a pointer, the caller should provide this data.

如果函数需要在一系列调用期间维持某些数据的状态，比如工作缓存或指针，那么调用者应该提供此数据。

This pre-conversion is critical for maintaining color state through transitions of different frames as their portions are blitted to the buffer and, eventually, the screen.

帧的局部经过位块传输后保存在缓冲区，最终在屏幕显示。 这种预转换通过帧间转换，对保持色彩状态十分重要。

This changes the state of the buffer to FULL.

这样就把缓冲的状态变成FULL。

Because the state of the internal buffer is FULL, the available data is returned and a notify issued.

因为内部缓冲的状态是FULL，所以可用数据将被返回，并发出一个notify 。

As we know, we also need to add a sequence number and a state (IOType variable, IOZeroReadCompleted, etc.) to our buffer.

众所周知，我们也需要添加序号和状态(IOType变量，IOZeroReadCompleted，等等)到我们的缓冲中。