3d objects undulating as if floating in the ocean

[Robert Paynter]

ok I think I got it. so I changed the position expression to move on the z and hooked up the values to sliders. I then used the roatation expression and hooked them up to the same sliders and added a damping slider.. it’s looking pretty good

position:
xAmp = thisComp.layer(“Null 10”).effect(“Amp”)(“Slider”); //height of undulations (pixels)
xFreq = thisComp.layer(“Null 10”).effect(“Freq”)(“Slider”); //undulations per second
xSpeed = thisComp.layer(“Null 10”).effect(“Speed”)(“Slider”); //speed of wave (pixels per second)

wl = xSpeed/xFreq; //wavelength (pixels)
phaseOffset = ((position[0]%wl)/wl)*2*Math.PI;
z = xAmp*Math.sin(2*Math.PI*xFreq*time + phaseOffset);
value + [0,1,z]

rotation:
xFreq = thisComp.layer(“Null 10”).effect(“Freq”)(“Slider”); //undulations per second
xSpeed = thisComp.layer(“Null 10”).effect(“Speed”)(“Slider”); //speed of wave (pixels per second)
damping = thisComp.layer(“Null 10”).effect(“Damp”)(“Slider”); //undulation damping factor

wl = xSpeed/xFreq; //wavelength (pixels)
phaseOffset = ((position[0]%wl)/wl)*2*Math.PI;
theta = Math.atan(Math.cos(2*Math.PI*xFreq*time + phaseOffset));
radiansToDegrees(theta)/damping;

[Dan Ebberts]

I think I’d try the noise() function for this. If you have your layers laid out in x and y, this should give you the undulation in z and otation in x and y:

// position

xyCompress = 500;
speedCompress = 1;
amplitude = 50;
x = value[0];
y = value[1];
z = amplitude*noise([x/xyCompress,y/xyCompress,time/speedCompress]);
[x,y,z]

// x rotation

xyCompress = 500;
speedCompress = 1;
amplitude = 50;
x = transform.position[0];
y = transform.position[0];
z0 = amplitude*noise([x/xyCompress,(y-.1)/xyCompress,time/speedCompress]);
z1 = amplitude*noise([x/xyCompress,(y+.1)/xyCompress,time/speedCompress]);
radiansToDegrees(Math.atan2(z0-z1,.2))

// y rotation

xyCompress = 500;
speedCompress = 1;
amplitude = 50;
x = transform.position[0];
y = transform.position[0];
z0 = amplitude*noise([(x-.1)/xyCompress,y/xyCompress,time/speedCompress]);
z1 = amplitude*noise([(x+.1)/xyCompress,y/xyCompress,time/speedCompress]);
radiansToDegrees(Math.atan2(z1-z0,.2))

You’ll want to adjust the first three parameters to suit your needs (actually you should probably tie them to controls).

Dan

[Robert Paynter]

I’ll give it a try
Thanks Dan.