• Adobe After Effects Expressions

  Bouncing Ball/Sine Wave Motion in between two 3d points.

  Posted by Satya Meka on March 30, 2009 at 4:08 am

  Ok, I am stuck up with this thing, I need a ball to bounce in 3d space on a surface randomly(elastic). I am creating the random values using wiggle. But I am having hard time figuring out to create an expression so that the layer/ball bounces in 3d space on a surface.

  regards,
  Satya.

  Satya Meka replied 17 years, 4 months ago 2 Members · 3 Replies
• 3 Replies

• 

  Filip Vandueren

  March 30, 2009 at 2:18 pm

  something like this:

  
floorLevel=207;
ballRadius=25;

  segDur = .5;// duration of each "segment" of random motion
  minVal = [0.25*thisComp.width, -0.75*thisComp.height];
  maxVal = [0.75*thisComp.width, 0.75*thisComp.height];

  seed = Math.floor(time/segDur);
  segStart = seed*segDur;
  seedRandom(seed,true);
  startVal = random(minVal,maxVal);
  seedRandom(seed+1,true);
  endVal = random(minVal,maxVal);

  h=length(startVal,endVal);

  xz=linear(time,segStart,segStart + segDur, startVal, endVal);
  y=Math.sin((time%segDur)*(Math.PI/segDur))*h/2;

  y=floorLevel-y-ballRadius;

  [xz[0],y,xz[1]]
• 

  Satya Meka

  March 30, 2009 at 4:00 pm

  Thank you for you quick reply. But I think I need to explain the scene more. I am trying to do a animation like this. https://www.eamaemirkin.com/site/echo/. I chose a point light(w/trapcode lux) to bounce on a surface, some how I still couldn’t get it right. I very much appreciate your help.

  Satya.

  Satya Meka,
  https://www.gutsblow.com
• 

  Satya Meka

  March 30, 2009 at 4:19 pm

  Actually, its my bad! I screwed my camera in my comp, so it didnt show well… but when i opened a new comp, it worked like a charm! Thanks a million!

  Satya Meka,
  https://www.gutsblow.com

Reply to this Discussion! Login or Sign Up