Resolution Independent Curve Rendering using Programmable Graphics Hardware

Charles Loop, Jim Blinn

July 2005 Transactions on Graphics (TOG) - (Siggraph 2005) |

Published by Association for Computing Machinery, Inc.

We present a method for resolution independent rendering of paths and bounded regions, defined by quadratic and cubic spline curves, that leverages the parallelism of programmable graphics hardware to achieve high performance. A simple implicit equation for a parametric curve is found in a space that can be thought of as an analog to texture space. The image of a curve’s B’ezier control points are found in this space and assigned to the control points as texture coordinates. When the triangle(s) corresponding to the B’ezier curve control hull are rendered, a pixel shader program evaluates the implicit equation for a pixel’s interpolated texture coordinates to determine an inside/outside test for the curve. We extend our technique to handle anti-aliasing of boundaries. We also construct a vector image from mosaics of triangulated B’ezier control points and show how to deform such images to create resolution independent texture on three dimensional objects.