Space Pen investigates the possibilities of editing
3D geometry by simply drawing on any surface you want to modify. Currently,
the system enables users to draw on any surface or click to leave
a comment. Space Pen can also recognize some simple shapes (like circles,
rectangles, triangles or arrows) drawn in space.
Space Pen also displays a floor plan of the 3D
model. The floor plan is automatically calculated from the model and
shows the user's location and orientation in real time.
A recent adition allows drawing with light. The
"light pen" will indicate were to place a light to obtain
the desired illumination of the space.