Managing augmented-reality graphical elements under power constraints

A system comprising:

• a display comprising a plurality of zones whose luminance is individually controllable;
• and
• at least one processor configured to:
• identify a plurality of graphical elements to be presented in a sequence of images;
• for each graphical element of the plurality of graphical elements, determine a corresponding importance level;
• for each graphical element of the plurality of graphical elements, determine a corresponding set of zones of the plurality of zones within the display that are to be used to present each graphical element;
• for each zone of the corresponding set of zones, determine a minimum luminance level and a maximum luminance level, based on at least one graphical element of the plurality of graphical elements to be presented by each zone, and an importance level of the at least one graphical element;
• for each zone of the corresponding set of zones, estimate a minimum power consumption value and a maximum power consumption value, based on a respective minimum luminance level and a respective maximum luminance level;
• calculate a maximum total power consumption value for the display, by summing maximum power consumption values of the plurality of zones;
• determine whether the maximum total power consumption value exceeds a current power budget of the display;
• and
• when it is determined that the maximum total power consumption value exceeds the current power budget,
• identify first zones of the plurality of zones that correspond to at least one graphical element having a lowest importance level of the plurality of graphical elements;
• and
• adjust luminance levels of the first zones to lie between respective minimum luminance levels and respective maximum luminance levels, until a first adjusted total power consumption value of the display does not exceed the current power budget;
• determine when at least one first zone of the corresponding set of zones corresponds to both a first graphical element having a first importance level and a first portion of a second graphical element having a second importance level that is lower than the first importance level, and when at least one second zone corresponds to a second portion of the second graphical element only;
• and
• when it is determined that the at least one first zone corresponds to both the first graphical element and the first portion of the second graphical element, and the at least one second zone corresponds to the second portion of the second graphical element only,
• drive the at least one first zone at a first luminance level corresponding to the first importance level and the at least one second zone at a second luminance level corresponding to the second importance level;
• and
• adjust a rendered intensity of the first portion of the second graphical element in the sequence of images, to match an estimated perceived luminance of the first portion of the second graphical element with an estimated perceived luminance of the second portion of the second graphical element.