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Index › Programming Questions & Help › Syntax Questions › increment/decrement

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increment/decrement (Read 466 times)

annemarie

increment/decrement
Jul 24^th, 2006, 8:08pm

Hi all,

I would like to fade in/fade out the tint of an image:
I looked at the examples for increment/decrement, but I don't get how to modify the code so that it works. How do I modify this code so that the alpha channel fades in and out?

int a = 0; a++; if(a > 1) { a = 255; }
tint(255, 255, 255, a);
image(video, 200, 200);

Thanks for helping a beginner:)

st33d

Re: increment/decrement
Reply #1 - Jul 24^th, 2006, 11:50pm

So you're saying a = 0. Then plus one to a. Then if a is greater than one immediately change a to 255. I think you have your logic a bit backwards. I have a couple of examples below. I hope they help.

http://www.robotacid.com/PBeta/fader/index.html

Code:


float fade = 0.0;
void setup(){
  //get images etc.
}
void draw(){
  background(0);
  if(a < 255){
    a += 0.3;
    tint(255, 255, 255, fade);
  }
  image(video, 200, 200);
}

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