Fiducial rings in virtual reality

A system comprising:

• a fiducial ring including:
• a ring body that includes a plurality of fiducial markers that each are positioned at different locations on the ring body and each are active devices emitting light;
• an imaging device configured to capture one or more images of the fiducial ring by capturing the light emitted from at least one of the fiducial markers;
• and
• a console comprising a processor and a memory coupled to the processor, the memory including instructions that, when executed by the processor, cause the processor to:
• receive the one or more image images from the imaging device, the one or more images including an image with a fiducial marker, of the plurality of fiducial markers,
• determine a location on the fiducial ring that corresponds to the imaged fiducial marker,
• determine a position of the fiducial ring based at least in part on the determined location of the fiducial marker on the fiducial ring, and
• provide content to a head-mounted display (HMD) based on the determined position of the fiducial ring.

A system comprising:

• a fiducial ring including:
• a ring body that includes a plurality of fiducial markers that each are positioned at different locations on the ring body and each are active devices emitting light, the ring body configured to fit on a portion of a user's finger;
• an imaging device configured capture one or more images of the fiducial ring;
• and
• a console configured to provide content to a head-mounted display (HMD) based in part on the one or more images of the fiducial ring.