Object Composition

For right now:

  1. Objects must be rigid to be compatible.
  2. All objects must be metal. The conductive properties of metal objects allow them to be read by projected capacitance touch screens. Projected capacitance touch screens were selected due to their superior multi-touch capabilities.

Triangular Points

Each object must have three conductive points below its base. These points can be anywhere below the base of the object, but must have a distinct arrangement as described below.

Two of the conductive points should be closer to each other than either is from the third point. This third conductive point is referred to as the “lead point”. (We’ll use LP from now on for “lead point”.) The other two points are the “orientation points” (OPs). The orientation of the object is determined by calculating the direction of the line that starts at the midpoint of the OPs and ends at LP.

Results of layout of LP and OPs

The distance from the LP to the OPs doesn’t matter as long as the OPs are closer to each other than to the LP. OPs are exclusively used to determine the orientation and have nothing to do with determining the object’s dimensions.

Note: The number of OPs could be reduced to two points if a screen could determine the type of point, perhaps by comparing size or other distinct signature.

Refer to appendix C on how to add conductive points to an object

Cite: The idea for the three point system was inspired by Vivien Cormier’s solution.