This article introduces quadrature prefiltering, an accurate, efficien
t, and fairly simple algorithm for prefiltering polygons for scanline
rendering. It renders very high quality images at reasonable cost, str
ongly suppressing aliasing artifacts. For equivalent RMS error, quadra
ture prefiltering is significantly faster than either uniform or jitte
red supersampling. Quadrature prefiltering is simple to implement and
space-efficient; it needs only a small two-dimensional lookup table, e
ven when computing nonradially symmetric filter kernels. Previous algo
rithms have required either three-dimensional tables or a restriction
to radially symmetric filter kernels. Though only slightly more compli
cated to implement than the widely used box prefiltering method, quadr
ature prefiltering can generate images with much less visible aliasing
artifacts.