Hello,
The following code works well but I don't understand why the mysteryEffect code
block changes the picture.
Doesn’t 64*(r/64) just equal r? (Same with g and b.) So this function should
not change the picture at all. But it does! If anyone can explain how and why
this actually changes the picture I would appreciate it greatly.
#Creates, duplicates and shows the pic
def main():
pic1= makePicture( pickAFile() )
pic2= duplicatePicture( pic1)
fadeDownFromBlack( pic1 )
show( pic1 )
mysteryEffect( pic2 )
show( pic2 )
#Does a 50% fade of the upper half of the picture
def fadeDownFromBlack( pic1 ):
w=getWidth(pic1)
h=getHeight(pic1)
for y in range(0,h/2):
for x in range(0,w):
px= getPixel( pic1, x, y )
setRed(px,y*(2.0/h)*getRed(px))
setGreen(px,y*(2.0/h)*getGreen(px))
setBlue(px,y*(2.0/h)*getBlue(px))
repaint( pic1 )
#Adds a rainbow effect to the picture
def mysteryEffect( pic2 ):
for px in getPixels( pic2 ):
r= getRed ( px )
g= getGreen( px )
b= getBlue( px )
setRed( px, 64*(r/64))
setGreen( px, 64*(g/64))
setBlue( px, 64*(b/64))
repaint( pic2 )
Thanks,
Joe
_______________________________________________
Tutor maillist - Tutor@python.org
To unsubscribe or change subscription options:
http://mail.python.org/mailman/listinfo/tutor
