Commit d7383b7b86bf9d8e37d73d2ac1a7fec54d8f746e
2012-12-20T01:03:22
[base] Improve trigonometric core. FreeType used to rely on a 24-step iteration CORDIC algorithm to calculate trigonometric functions and rotate vectors. It turns out that once the vector is in the right half-plane, the initial rotation by 63 degrees is not necessary. The algorithm is perfectly capable to converge to any angle starting from the second 45 degree rotation. This patch removes the first rotation and makes it a 23-step CORDIC algorithm. * src/base/fttrigon.c (FT_TRIG_SCALE, FT_TRIG_COSCALE): Update macro values. (ft_trig_pseudo_rotate, ft_trig_pseudo_polarize): Remove initial rotation.