• Adobe After Effects Expressions

  “DVD screeensaver” change color when bouncing off the wall

  Posted by Peter Toth on January 6, 2020 at 7:13 am

  Hi everyone,

  I’m trying to do a “DVD screensaver” via AE expressions. (Like this) I’m at the point when the bouncing works perfectly, but I don’t know how to achieve the “when bouncing change the color” thing. Actually it should pick a random value for Colorize Hue – I think – . It should work via expression, not by keyframes, because I want it to work with any comp size, and length.

  Can anybody help me? Thanks ☺
  Here is the position bouncing part below. The margins has been calculated from the DVD logo.

  hSpeed= 222;
vSpeed= 200;

  marginh = 76;
  marginw = 175;

  cw=thisComp.width - marginw*2;
  ch=thisComp.height -marginh*2;
  x = value[0] - marginw + time*hSpeed;
  y = value[1] - marginh + time*vSpeed;
  x = x<0 ? -x : x;
  x%=2*cw;
  x = x>cw ? (2*cw)-x : x;

  y = y<0 ? -y : y;
  y%=2*ch;
  y = y>ch ? (2*ch)-y : y;

  [x,y]+[marginw,marginh]

  Peter Toth replied 6 years, 7 months ago 2 Members · 2 Replies
• 2 Replies

• 

  Andrei Popa

  January 6, 2020 at 6:11 pm

  Add a fill property with this expression to its color.

  
startX = position.valueAtTime(0)[0];
startY = position.valueAtTime(0)[1];
hSpeed= 222;
vSpeed= 200;

  marginh = 76;
  marginw = 175;

  cw=thisComp.width - marginw*2;
ch=thisComp.height -marginh*2;
x = startX - marginw + time*hSpeed;
y = startY - marginh + time*vSpeed;
s = Math.floor(x/cw)+Math.floor(y/ch);
seedRandom(s,true);
random([1,1,1]) + [0,0,0,1]


  Andrei
  My Envato portfolio.
• 

  Peter Toth

  January 6, 2020 at 7:17 pm

  Thank You ☺ Works like a charm

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