Major restructuring of how streams work. Neither input nor output
streams are now blocking. This avoids stalling the rest of the client or
server when a peer is slow or unresponsive.
Note that this puts an extra burden on users of streams to make sure
they are allowed to do their work once the underlying transports are
ready (e.g. monitoring fds).
Allow conditional dependencies between rects when decoding
Some encodings only cause dependencies between rects some of the
time. Make sure we can allow parallel decoding of those rect that
aren't dependent on each other.
We need to split these steps up in preparation for multi-core
support. Reading needs to be done in a serial manner, whilst
decoding can be done in parallel.
This also involved a rather large cleanup of the Tight decoder.
Move image encoding logic into a central EncodeManager class
This allows us to apply a lot more server logic
independently of which encoder is in use.
Most of this class are things moved over from the
Tight encoder.
Use PixelBuffer objects as the interface for encoders and decoders
This avoid a lot of unnecessary middle men. This also pushes the
responsibility for pixel format conversion into the encoders and
decoders. The new bufferFromBuffer() is used for direct conversion,
rather than PixelTransformer/TransImageGetter.
Encoders/decoders should track the connection object
The connection object is a much more appropriate object for the
decoders and encoders to keep track of. Besides the streams, it also
contains state like connection parameters.
If the client and server are using identical pixel formats, then perform Tight decoding directly into the viewer's back buffer, rather than going through the slow fillRect/imageRect routines.