Patent ID: 6111582
Filing Date: 2000-08-29
Classification: G06T

Abstract:
A method of generating a computer generated image sequence from primitives stored in a list of visible primitives, wherein said image sequence comprises consecutive frames representing simultaneous viewpoint translation and view direction vector rotation, the method comprising the steps of:a) transforming graphics primitives visible in a previous frame by a translational component of a view transformation;b) repositioning extents of a viewport on a viewplane by an amount that reflects a view direction vector rotation angle;c) classifying previously visible primitives to the repositioned viewport;d) rasterizing the previously visible primitives into the repositioned viewport;e) storing, in an augmented depth buffer, both depth value and primitive references for image samples produced by rasterizing each of the previously visible primitives for the previous frame and a current frame;f) determining, using said augmented depth buffer after the step e) of storing, locations in the current frame where previously invisible primitives may be newly exposed by finding in corresponding locations of said augmented depth buffer, locations in which:1) a first primitive of the previously visible primitives rasterized for the current frame belongs to a different substantially convex object than a second primitive of the previously visible primitives rasterized in the corresponding location for a preceding frame, and2) depth values of the locations for the current frame are greater than the depth values for the preceding frame;g) searching in the locations to find newly visible primitives using visibility tracing;h) rasterizing the newly visible primitives using depth-comparison rasterization;i) adding the newly exposed primitives to the list of visible primitives; andj) repositioning the image samples, produced by rasterizing the primitives which are not yet rotated, by rotating the image samples by an amount that reflects the view direction vector rotation.