[Kst] Curve drawing time

[George Staikos]

Almost all time spent in curve drawing is spent inside the large loop in 
drawlines.  The rest is insignificant.  This code is completely undocumented 
and uses so many 1/2/3 letter variables it's very hard to dig into.  One 
thing I did notice is that it could use statistic optimizations on 
conditionals.  There are some multi-case if()s that have the common case 
last....  It would be a lot easier to debug this if we could extract the 
curve drawing code (as I suggested a while ago with KstCurveDrawer class 
hierarchy), and then wrote testcases for it.  Then we could automate 
regression testing of drawing too.

-- 
George Staikos
KDE Developer				http://www.kde.org/
Staikos Computing Services Inc.		http://www.staikos.net/