[REBOL] Re: draw question
From: cyphre:seznam:cz at: 25-Oct-2002 13:59
Hello Bruno and all,
I'm not sure if I understand you well but here is a simple example how to
use DRAW dialect for "painting" into alpha channel of the image. I think
with the function make-alpha (bellow in the example) you can draw almost any
kind of transparent shape though it is not the fastest method....IMO the
possibility to use DRAW pens for alpha channel should be done at Rebol's
native level...What dou you think Holger? ;-)
!!watch out line breaks!!
--------------<code>-------------
make-alpha: func [fx img /local idx][
append fx 'grayscale
fx: to-block mold to-image make face [
size: img/size
effect: fx
edge: none
]
fx: fx/3/2
img: to-block mold img
idx: 0
remove-each i fx [
idx: idx + 1
either idx > 1 [
if idx = 3 [idx: 0]
true
][
false
]
]
append img/3 fx
return do load img
]
pic: load-thru/binary http://www.rebol.cz/~cyphre/bay.jpg
view layout [
backdrop effect reduce ['gradient red orange]
image make-alpha [
gradient 1x1 0.0.0 255.255.255
draw [
pen 0.0.0
fill-pen 200.200.200
circle 100x80 50
fill-pen 0.0.0
box 80x80 125x125
]
] pic
]
-----------------------------<end of code>-------------------------------
regards,
Cyphre
