*paintPreProcess
ʐFCB
**Tv
摜2l ʐFC쐬܂B
PȂlł͂ȂF̃gX͂Əo悤ɉH܂B
**g

-ctl(1)́A[baseClip]	ɕ`̐c̑̒(default 0)
-ctl(0)́A[bgClip]	̒q̍dєwimCY̏(default 255)
-ctl(2)́A[threshold]	`̓r؂̒(default 127)
ƂĎgpB
**\[X
---(
r:
put(scl(min(min(r,g),b),ctl(1),ctl(0),0,255)<ctl(2)? 0:255,0),
get(0)

g:
get(0)

b:
get(0)

a:
a
---)
**Zp

 RGBe`l̍ŏl擾Ĉꎟf[^ƂāA
 ꎟf[^ctl(1)-ctl(0)͈͂ŃNbvA
 0-255Ƀ}bsOA
 ctl(2)lɂēlĂ܂B

At@`l͍sĂ܂̂ŁA
KvɂĂƂʂɃAt@ĂB
