Commit 2ea511eed81770f423544525adebf7f954b8be93
2019-04-29T22:49:15
[smooth] Simplify cubic Bézier flattening. The previous implementation is correct but it is too complex. The revised algorithm is based on the fact that each split moves the control points closer to the trisection points on the chord. The corresponding distances are good surrogates for the curve deviation from the straight line. This cubic flattening algorithm is somewhat similar to the conic algorithm based the distance from the control point to the middle of the chord. The cubic distances, however, decrease less predictably but are easy enough to calculate on each step. * src/smooth/ftgrays.c (gray_render_cubic): Replace the split condition.