Abstract:
Because of the resolution independent nature of vector graphics images,
it is useful to consider using them directly as textures in
3D rendering.
Spline curves are used to represent boundaries in standard vector graphics
representations.
Antialiased rendering of such content can be obtained by soft thresholding
an implicit representation of these boundary features.
The distance function
is an especially useful implicit representation, and
an accurate distance can also be used for special effects such as embossing
and stroke texturing.
Unfortunately, computation of the true distance to a spline curve
is expensive.
Therefore, normally either the distance is approximated
or the spline curves are approximated with simpler primitives
for which an accurate distance can be computed.
Approximation with line segments gives only C0
continuity.
We approximate spline curves using circular arcs instead.
This approximation has C1
continuity,
and computing the distance to a circular arc is nearly
equivalent in expense to computing the distance to a line segment.
Vector images
