by raf » Mon Jan 31, 2011 2:52 pm
Yes, Apple Cinema displays are really nice monitors, I have to agree.
Unfortunately, the way the VNC protocol works is by sending the whole screen over the line. Your system needs a lot of RAM in order to be able to display such large screens.
Example, if your monitors are say 1600x1200 and say 1680x1050. Then you would need this much RAM on your iOS device:
1600x1200x32BPP = 60MB x 2 (frontbuffer and backbuffer) = 120MB
PLUS
1680x1050x32BPP = 54MB x 2 = 108MB.
That means you need 228MB FREE memory on your device.
The iPad has only 256MB of RAM total, and that is used by the OS and any running applications; so there is no physical way to do it with this little RAM.
One possible fix would be to down-scale the screen buffer before sending it to the VNC client. This feature is called server-scaling; and is not supported by the stock Apple VNC server. It is supported by some 3rd party VNC servers in other OSs, and Remoter will support this in the near future.
Another option is for a way for the client and server to determine which of the two monitors to display. This is supported by the Apple VNC server, but as a proprietary extension that is not part of the open RFB protocol. I'm planning on offering support for this as well, but it might take some time.
Raf.