APPARATUS AND METHOD FOR FRAGMENT OPERATIONS IN A 3D-GRAPHICS PIPELINE

摘要

Apparatus and method for rendering 3D-graphics images. The apparatus includes a port for receiving commands from a graphics application, an output for sending a rendered image to a display and a fragment-operations pipeline, coupled to the port and to the output, the pipeline (2MO) including a stage for performing a fragment operation on a per-pixel basis and on a per-sample basis. Performing on a per-pixel basis one of the following test stages: scissor, stipple (2BO), alpha (2CO) or color (2DO). Performing on a per-sample basis one of the following test stages: Z (2EO), blending (2FO) or dithering (2GO). The apparatus programmatically selects the following: whether to perform a stencil test (2EO) on a per-pixel or a per-sample basis and performs the stencil test (2EO) on the selected basis, pixel samples for per-sample operations, where the samples differ with different instances of the same per-sample operation, a set of subdivisions of a pixel as samples for use in the per-sample fragment operation, programmatically assigns different weights to at least two samples, and performs the per-sample operation using the programmatically selected and differently weighted samples.