Patent ID: 7564470

Claim:
A computer program product comprising one or more computer-readable storage media having stored computer-executable instructions which, when executed by a computing system having a processor, implement a method for compositing an image having a plurality of sources in a system that includes a display device for displaying the image, wherein the method comprises: the computing system dividing the image into slices, each slice including at least one line; the computing system dividing each line in each slice into at least one span, wherein each span has at least one associated source included in the plurality of sources and each span in each slice has the same at least one associated source; for each span in each line, the computing system reading data directly from the associated source without reading the data as part of a composite image from a buffer; the computing system identifying portions of the image that are opaque and portions of the image that are translucent; for each portion of the image that is translucent, the computing system reading, blending and displaying the data from the sources corresponding to the translucent portion; for each portion of the image that is opaque, the computing system reading only from the sources that correspond to the opaque portion and that would be visible within the opaque portion during display of the image, and without reading data from any sources that would otherwise be obscured in the opaque portion during display of the image.