Camera based safety mechanisms for users of head mounted displays

A method for using a head mounted display, the method comprising:

• providing interactive content for rendering on a display portion of the head mounted display (HMD) worn by a user, the HMD when worn by the user is configured to block a view to a real-world environment;
• receiving images of a physical environment in a vicinity of the user wearing the head mounted display while the user is viewing the interactive content;
• tracking location information of the user wearing the HMD as the user is interacting with the interactive content, wherein the location information is tracked in relation to an area within the physical environment in which the user is able to move around while interacting with the interactive content, the area defined by calibration based on an amount of space available for the user to move within the physical environment;
• determining the user approaching an edge of a safe interaction zone defined in the area of the physical environment while interacting with the interactive content that is being rendered on the display portion of the HMD;
• and
• adding a highlighted indicator to the interactive content currently being rendered on the display portion of the HMD, the highlighted indicator indicative of the edge of the safe interaction zone defined in the area of the physical environment in which the user is interacting with the interactive content.