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simple fade (Read 966 times)
kngpengwin
simple fade
Jul 11th, 2007, 5:15am  
I've got what's probably a really simple problem....

I'm trying to create a smooth fade effect that will cover black shapes with a white overlay. I thought I could draw a series of white rectangles over the whole stage, building up opacity until the stage went to white, but the black never gets covered all the way.

what's a better way to fade to white? what am I doing wrong?

link:
http://www.divinepenguin.com/processing/fadetest/

Quote:

int stageHeight = 300;
int stageWidth = 300;
int count = 0;

void setup(){
 size(stageWidth,stageHeight);
 background(255);
 noStroke();
 fill(0);
 ellipse(150,150,50,50);
}

void draw(){
 fill(255,5);
 rect(0,0,stageWidth,stageHeight);
 count ++;
 if (count > 50){
   fill(0);
   ellipse(random(stageWidth),random(stageHeight),50,50);
   count = 0;
 }
}



tia!
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fjen
Re: simple fade
Reply #1 - Jul 11th, 2007, 7:59am  
this is a known effect and has been discussed before. please try and search the forum for "fade" or "opacity" ..

F
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kngpengwin
Re: simple fade
Reply #2 - Jul 11th, 2007, 7:09pm  
I'm sorry if my question was redundant...I looked around but didn't find a solution that would work.

I managed to do what I needed to do by manipulating the pixel array directly. it seems just as fast and offers more flexibility than drawing a rectangle, so I guess it's a better solution in the long run.

Quote:


int stageHeight = 300;
int stageWidth = 300;
int fadeSpeed = 25;

void setup(){
 size(stageWidth,stageHeight);
 background(255,255,255);
 noStroke();
 smooth();
 fill(0);
}

void draw(){
 ellipse(random(stageWidth),random(stageHeight),50,50);
 fadeScreen();
}

void fadeScreen(){
 loadPixels();
 for(int i=0; i<pixels.length; i++){
   pixels[i] = color(red(pixels[i])+fadeSpeed,green(pixels[i])+fadeSpeed,blue(pixels[i])+fadeSpeed);
 }
 updatePixels();
}
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