[Dan Ebberts]

Something like this time remapping expression maybe:

dur = 5; // play each clip 5 seconds
seed = 1103; // change this to get different result
m = marker;
val = time;
if (m.numKeys > 0){
  period = Math.floor(time/dur);
  t = time%dur;
  seedRandom(seed+period,true);
  n = Math.floor(random(m.numKeys)) + 1;
  val = m.key(n).time + t;
}
val

[Dan Ebberts]

I think the whole problem gets simpler if you switch from rectangular coordinates to polar coordinates (radius and angle). Then a circular random distribution centered around the comp center becomes something like this:

c = [thisComp.width,thisComp.height]/2; // center
rMax = 500; // max radius
seedRandom(index,true);
a = random(Math.PI*2);
r = random(rMax);
x = r*Math.cos(a);
y = r*Math.sin(a);
c + [x,y]

It gets more complicated if you have a rectangular exclusion zone in the center of the field, but by using a little trig, you can avoid the while loop that can hang AE:

c = [thisComp.width,thisComp.height]/2; // center
w = 400; // width of rectangular exclusion area
h = 300; // height of rectangular exclusion area
rMax = 500; // max radius (must be big enough to enclose the rectangle)
seedRandom(index,true);
a = random(Math.PI/2);
aMid = Math.atan2(h/2,w/2);
if (a < aMid){
  rMin = (w/2)/Math.cos(a);
}else{
  rMin = (h/2)/Math.cos(Math.PI/2 - a);
}
r = random(rMin,rMax);
x = r*Math.cos(a);
y = r*Math.sin(a);
n = Math.floor(random(4));
if (n == 1){
  x = -x;
}else if (n == 2){
  x = -x;
  y = -y;
}else if (n == 3){
  y = -y;
}
c + [x,y]

[Dan Ebberts]

This may not be what you’re after, as it requires the checkbox to be keyframed to on when you want the child’s x position to follow changes in the parent’s x position:

p = thisComp.layer("parent").transform.xPosition;
cb = effect("Checkbox Control")("Checkbox");
accum = value-value;
if (cb.numKeys > 0){
  n = 0;
  n = cb.nearestKey(time).index;
  if (cb.key(n).time > time) n--;
  if (n > 1){
    if (cb.key(n).value) accum += p - p.valueAtTime(cb.key(n).time);
    for (i = n-1; i > 0; i--){
      if (cb.key(i).value) accum += p.valueAtTime(cb.key(i+1).time) - p.valueAtTime(cb.key(i).time);
    }
    if (cb.key(1).value) accum += p.valueAtTime(cb.key(1).time) - p.valueAtTime(0);
  }
}else{
  if (cb.value) accum = p - p.valueAtTime(0);
}
value + accum

[Dan Ebberts]

This should work, but there might be a more efficient way to do it, depending on what’s driving your value (for this example, I’m assuming the value is contained in a slider):

s = effect("Slider Control")("Slider");
f = timeToFrames(time);
above = s.valueAtTime(0) >= 1;
n = above ? 1 : 0;
for (i = 1; i <= f; i++){
  if (above){
    if (s.valueAtTime(framesToTime(i)) < 1){
      above = false;
    }
  }else{
    if (s.valueAtTime(framesToTime(i)) >= 1){
      n++;
      above = true;
    }
  }
}
n

[Dan Ebberts]

That’s considerably more complicated and will bog down in a longer comp because of the additional processing that needs to happen at each successive frame. Try this:

numFrames = 5; // change colors every 5 frames
c1 = effect("Color Control 1")("Color");
c2 = effect("Color Control 2")("Color");
c3 = effect("Color Control 3")("Color");
c4 = effect("Color Control 4")("Color");
c5 = effect("Color Control 5")("Color");
colors = [c1,c2,c3,c4,c5];
f = timeToFrames(time);
curPeriod = Math.floor(f/numFrames);
colorIdx = [];
seedRandom(0,true);
for (i = 0; i < value.length; i++){
  colorIdx.push(Math.floor(random(colors.length)));
}
i = 1;
while (i <= curPeriod){
  seedRandom(i,true);
  for (j = 0; j < value.length; j++){
    temp = colorIdx[j] + Math.floor(random(colors.length-1)) + 1;
    colorIdx[j] = temp%colors.length;
  }
  i++;
}
myExpr = "style";
for (i = 0; i < value.length; i++){
  myExpr += ".setFillColor(colors[colorIdx[" + i + "]]," + i + ",1)";
}
eval(myExpr)

[Dan Ebberts]

Do you mean so that each letter has a color different than the one next to it, or so that a letter doesn’t get the same color for two consecutive periods?

[Dan Ebberts]

Something like this should work. You might have to fiddle with it a bit:

s = effect("Slider Control")("Slider");
fadeDuration = .333;
t = s.key(textIndex+1).time;
ease(time,t,t+fadeDuration,100,0);

[Dan Ebberts]

It works for me if I change your fadeDuration from 10 to .333.

[Dan Ebberts]

This Source Text expression appears to work:

numFrames = 5; // change colors every 5 frames
c1 = effect("Color Control 1")("Color");
c2 = effect("Color Control 2")("Color");
c3 = effect("Color Control 3")("Color");
c4 = effect("Color Control 4")("Color");
c5 = effect("Color Control 5")("Color");
colors = [c1,c2,c3,c4,c5];
f = timeToFrames(time);
seed = Math.floor(f/numFrames);
seedRandom(seed,true);
myExpr = "style";
for (i = 0; i < value.length; i++){
  myExpr += ".setFillColor(colors[Math.floor(random(colors.length))]," + i + ",1)";
}
eval(myExpr)

[Dan Ebberts]

You could add a Position Animator and set its Position value to 0,30. Add an Expression Selector, delete the Range Selector, and use this expression for the Expression Selector’s Amount property:

s = effect("Slider Control")("Slider").value;
ease(s,textIndex,textIndex+1,100,0)

It uses the same slider as your Source Text expression.