METHOD OF AND APPARATUS FOR DISPLAYING AN OUTPUT SURFACE IN DATA PROCESSING SYSTEMS

摘要

A display controller provides an output frame to a display for display by sending respective output surface regions that together form the output frame, each respective region of the output surface being generated from a respective region or regions of one or more input surfaces, to the display. When a new version of an output surface region is generated, the display controller determines whether the output surface region has been unchanged for a period, and if it has, then stores the generated output surface region in a frame buffer. Then, for the subsequent frame, checks are performed to see if the output surface region could have changed. If there is no change the stored version of the output surface region is reused, but if there is a change in the output surface region, the output surface region is regenerated.

主权项

1. A method of providing an output surface, the output surface comprising one or more regions that together form the output surface, each respective region of the output surface being generated from a respective region or regions of one or more input surfaces; the method comprising:
when a new version of an output surface is to be provided, for at least one region of the output surface: checking whether a previously generated version for the at least one region of the output surface is stored in a buffer; and when a previously generated version for the at least one region of the output surface is not stored in the buffer: reading in the respective region or regions of the one or more input surfaces from which the at least one region of the output surface is to be generated, and generating a new version of the at least one region of the output surface from the respective region or regions of the one or more input surfaces; determining whether the at least one region of the output surface is likely to change; and when it is determined that the at least one region of the output surface is unlikely to change: sending the new version of the at least one region of the output surface for use and writing the new version of the at least one region of the output surface to the buffer.