GroupStorm SketchClient Building a “Push” style extension to PostBrainstorm Hans Andersen

PostBrainstorm has a bottleneck: Only one person can manipulate PostBrainstorm’s data at a time Other people can add ideas verbally, but they cannot add new content Users must take turns at the mural

Push vs. Pull PostBrainstorm uses a “pull” system to add external content - a user operating the board requests that content be added In a “push” system, devices external to the existing system deliver content to the board “Content” can be text, pictures, a URL… Anything that would be useful to display

Advantages of Push Multiple people, with multiple devices, can add content concurrently PostBrainstorm doesn’t need to know about the devices sending it data, so long as they conform to a standard interface New devices can be added or removed seamlessly

Example: the SketchClient Idea: group of people, each with their own pad of sticky notes, scribbling furiously Intuitive interface: tablet, pen, paper, and two buttons. “Disappearing computer” Actions: sketch, send, and clear Sketches appear nearly instantly on PostBrainstorm for later manipulation

Design Constraints Must work without modifying PostBrainstorm Must interact with Wacom tablet -> no Java Must be fast enough to be usable for brainstorming

the PostPicture event PostBrainstorm already has an interface for pushing pictures to the board Two step process: First, copy the picture over to iw-file; then, send a PostPicture event (id 6340) to the Eheap PostPicture has one custom field, “name”, which contains the picture’s file path The picture appears on the board

The Generic Process Generate an image in your application Run “convert” to make a jpeg Make it accessible to PostBrainstorm Run “postpicture” Java app

Problem: sending the image PostPicture event requires a Windows file name (\\iw-file\data\temp\mypic.jpg) Getting the picture to the right place can be tricky on a non-Windows machine Possibilities: WebDAV? scp?

Problem: The process is slow Upon sending the event, it can take a minute or more for the picture to appear Diagnosis? EHeap is slow (Tspaces?) Solution: EHeap2 is fast. Presumably, once PostBrainstorm is modified to use EHeap 2, it will be fast.

SketchClient in action

A note about performance... Transmit process takes 4-5 seconds in this demo However, the process of (EHeap2 registers event, MiniMural fetches event, downloads picture, scales picture, displays picture) takes <1 second! With a faster SketchClient, the transmit process could be as fast as 1-2 seconds

Future Possibilities Couple PostPicture with the Data Heap, so that just about any bitmap image can be sent & translated in a cross-platform manner More than just graphics - PostText, PostURL, PostSVG, etc. Other devices - a keyboard-based TextClient, or a scanner with 1-touch scan- and-post capabilities

More future possibilities Extend PostXYZ to allow finer control over posting (Control initial placement, scaling) Enable multiple PostBrainstorm systems to copy and share information