So... possible replacements for OpenCanvas.
I'm seeing one major obstacle to why things like Open Canvas don't take off more:
They require you to use/learn their tools to make art. This is rather a large obstacle to a lot of artists, who find the tools that work best for them, and don't like re-learning things over, and over, and over as times change.
So remove that requirement for the streaming tool to provide any actual art tools itself. What are you left with?
A tool much like join.me, but that server-side remembers a much larger canvas for multiple users, and can somehow broadcast both that large canvas (shrunk somehow?) to read-only viewers, and broadcast overlays (differences if you will) of that meta-canvas versus a given user's local canvas.
Handling conflicts is very difficult, but I'm realizing it may not be required to handle them transparently. Allowing for a simple interface for a given read/write user to pull a clipboard-like snapshot from the master-canvas they can paste into their own canvas would be sufficient I believe. It would allow for cooperative collaboration, not conflicting collaboration, but still allow for the social doodling-beside-each-other aspect.
But the basic idea would be define (with a client akin to Join.Me's) "here is my canvas" and "here are my scroll bars" and then begin streaming, or joining into an existing stream/meta-canvas. First person in defines the overall canvas dimensions, and the meta-stream says what those are right at the top, so new folks joining in know what size canvas to take (meta-canvas sized or smaller) and can tie in.
Crossposted:
scribbles on the wall, add your own scribble?