GPU-accelerated path rendering

摘要

This disclosure is directed to techniques for performing GPU-accelerated path rendering. A GPU is described that is configured to receive data indicative of a path segment of a path to be rendered, tessellate the path segment into a plurality of primitives, and render at least one of a fill area and a stroke area for the path segment based on the plurality of primitives. The techniques of this disclosure may be used to improve the performance of path rendering operations, to reduce memory bandwidth requirements needed to perform path rendering operations, and/or to reduce the memory footprint needed to perform path rendering operations.

主权项

1. A method comprising:
receiving, with a graphics processing unit (GPU), data indicative of a first path segment of a first path to be rendered and a second path segment of a second path to be rendered, the first path segment and the second path segment comprising respective two-dimensional vector graphics paths; tessellating, with the GPU, the first path segment into a first plurality of primitives and the second path segment into a second plurality of primitives; rendering, with the GPU, a fill area for the first path segment based on the first plurality of primitives, wherein the first plurality of primitives comprises a first plurality of line segments, and wherein rendering the fill area comprises:
generating, with the GPU, a first plurality of triangle primitives based on the first plurality of line segments, each of the first plurality of triangle primitives being generated based on a respective one of the first plurality of line segments;rendering, with the GPU, each of the first plurality of triangle primitives into a common stencil buffer such that the common stencil buffer stores data indicative of which pixels are inside of the fill area for the first path segment; andrendering, with the GPU, one or more first primitives that encompass the pixels that are inside of the fill area based on the data stored in the common stencil buffer and a fill color to generate a rasterized version of the fill area for the first path segment; and rendering, with the GPU, a stroke area for the second path segment based on the second plurality of primitives comprises a second plurality of line segments, and wherein rendering the stroke area comprises:
fattening, with a geometry shader of the GPU, the second plurality of line segments by shifting endpoints of the second plurality of line segments in positive and negative normal directions;generating, with the geometry shader of the GPU, a triangulation of the stroke area creating a second plurality of triangle primitives; andrendering, with the GPU, the second plurality of triangle primitives, wherein rendering comprises correcting overlapping portions of rendered second plurality of triangle primitives using a depth test, and the depth test configured to use data stored in the common stencil buffer without allocating a separate depth buffer.