Geometry drawing TUI
PROJECT SUMMARY
This project is a simple drawing application that was first demonstrated at the ACCAD open house during the Spring of 2008. The application utlizes Flash OSC and Reactivision to create a geometry drawing table using tangible drawing tools. Several participants can interact with the drawing table simultanneously. Each person has two tools, a modifier and a drawing tool. When the modifier is placed on the table alone it can be used to select one of 6 drawing modes: Free-Hand, Line, Triangle, Square, Circle, and Erase. After setting a mode use the drawing tool to draw shapes. In the Free-Hand mode, use the drawing tool to draw squiggles and curves. While in line mode, each time the tool is placed on the table and then lifted off a new point is set and a line is drawn to any previously set points. Place and lift the drawing tool on the table to draw circles, triangles, and squares. Rotate the tool while in a shape mode to rotate shapes. Swipe the erase tool over the drawing to erase. Place the modifier tool on the table at the same time as the drawing tool and new kinds of interaction become possible. Rotate the modifier to set the drawing color. While drawing shapes, move the modifier over the shape edges and the shape scales based on the distance between the drawing tool and the modifier.
AUDIENCE
A large number of students, teachers, staff, and their friends and family came to the ACCAD open house to see demonstrations of student work and emmerging technologies. It was an ideal time to showcase a multi-user interface like the geometry table, because there was a large number of people interested in interacting with the piece at one time. Kids were really drawn to the interface, but has some difficulties knowing know what it could do. Further iterations are being developed based on discoveries made during this exhibitions. In the next version I hope to increase the visibility of menus and include features and signage that make it easy for people to understand its capabilities without instruction.
Photography by Alan Price
INTERACTION
Interactive flow is dependant upon whether the tools are used alone or in combination.
When the modifier is used alone a menu appears. Rotate the tool and lift to set the drawing mode.
Move and rotate the drawing tool to set the location and orientation of shapes. Draw straight and curved lines in free-form and line modes. Erase mistakes in erase mode. In the next version I would like to includ emore subtle erasing, because the current version only has one erase mode that erases everything.
Use the modifier with the drawing tool to change the drawing color and resize shapes.
In the next version I will have an opportunity to use a new version of the Reactivision engine which was just recently released. This version enables finger tracking in addition to marker tracking. This will allow for some enhancements in the UI. A few ideas for enhancements would be the ability to manipulate shapes after they've been created and the ability to draw with multiple fingers simultaneously.
INTERFACE DISPLAY
Here's some examples of how the current interface works. Place the modifier on the table alone to open a drawing mode menu. Rotate the tool to target and lift to select a mode. During the open house many of the colors in the menu system were hard to read because the projector distorted contrast and color quite dramatically. In the new version these features of the menus need to be improved.
Another feature that I would like to add in the next version is some sound effects. I feel this could greatly improve usability because it would increase user awareness. Tones can be used to indicate when certain features have been selected. This feedback would be helpful for shape shape transformations, draw mode status and menu selections. In the current model, moving the modifier tool away from the drawing tool to increase the size of shapes and closer to decrease the size. The color of objects can only be changed while the object is being drawn by placing the modifier on the stage and rotate it. Every 10 degrees a tone and label indicates a color change and new color name.
SYNOPSIS OF CHANGES FOR NEXT VERSION
After demonstrating the table at the open house a few things became apparent with regard to the user interface of the TUIO Geometry Table. More feedback needs to be included in the system that informs users about the state of drawing modes being used. Also, feedback is needed in order to inform participants that their tool has been recognized after it has been placed on the table. Further enhancements to the interface could be made to coding and more time needs to be taken to correct bugs present within the programming. Currently the coding is written in Actionscript 2.0 and this needs to be upgraded to 3.0 for performance reasons.
In addition more robust tangible tools need to be constructed. There were issues during the exhibitions with the markers malfunctioning after passing through many hands once holding food and beverages. A more robust design is being developed with internal illumination and a protective coating.