Processing 1.0 - Processing Discourse - transparency in gif and pngs

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Index › Programming Questions & Help › Programs › transparency in gif and pngs

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transparency in gif and pngs (Read 604 times)

disablek YaBB Newbies Offline Posts: 48	transparency in gif and pngs Jan 14^th, 2008, 11:20pm I've been trying to load up a transparent gif/png as a PImage, and copied into another PImage. But the transparency is not retained. Is that supposed to happen?

mflux Senior Member Offline Posts: 388	Re: transparency in gif and pngs Reply #1 - Jan 15^th, 2008, 9:47am they should be retained. post the image somewhere online?
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disablek

Re: transparency in gif and pngs
Reply #2 - Jan 16^th, 2008, 8:56am

PImage a,b;

void setup(){
size(1200,800);
a=loadImage("pic.png"); // and the gif version as well
background(255);
b=new PImage(400,500);
b.copy(a,50,50,400,500,0,0,400,500);

}

void draw(){
background(255);
image(a,0,0);
//image(a,random(800),random(500));
image(a,400,50);
image(b,400,400);

}

the copied image doesn't retain alpha at all for either the png or the gif version.

!!!

extrapixel Full Member Offline Posts: 210 Switzerland	Re: transparency in gif and pngs Reply #3 - Jan 16^th, 2008, 2:50pm it's because the PImage "b" is created with RGB color, while you want it to be ARGB (including alpha). So, replace your line b=new PImage(400,500); with b=new PImage(400,500,ARGB); et voilà!
	http://www.extrapixel.ch

disablek YaBB Newbies Offline Posts: 48	Re: transparency in gif and pngs Reply #4 - Jan 16^th, 2008, 5:51pm Hey that's great! The reference documentation never showed that particular constructor signature.

disablek YaBB Newbies Offline Posts: 48	Re: transparency in gif and pngs Reply #5 - Jan 16^th, 2008, 5:55pm Oh is there anyway to toggle the transparency of a PImage?

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