Abstract: When a mobile device comes within a proximity of one or more accessories, the one or more accessories can generate an indication for sending to the mobile device. The indication can be based on a state of the one or more accessories and can include state information. The indication can be used to communicate state information about the one or more accessories to the mobile device.

Abstract: A system and method provide for determining in a computer system the intersections between a plurality of rays residing in three dimensional (3D) space and one or more surface elements residing in the 3D space. The rays or lines corresponding to the rays share a common intersection point. The method includes for each of the rays, storing the intersection point of the ray with a projection surface in the 3D space in a data structure in the computer system. For each of the surface elements, determining using projection a two-dimensional (2D) region representing the projection of the surface element onto the projection surface; and determining using intersection testing which points stored in the data structure are inside the 2D region. The points determined to be inside the 2D region represent intersection points between the surface element and the rays corresponding to the points.