AE-Expressions

A collection of usefull AE expressions

Hide backside on 3D flip

Add this nifty Dan expression to the Opacity of the front (will be on top in the stack) layer (Copy the expression, Alt-Click the Opacity Stopwatch, then Paste, hit Enter) source:

if (toCompVec([0, 0, 1])[2] > 0 ) { 
  value 
} else { 
  0 
}

Get sizes of layer

Get size of text layer.

thisComp.layer("My Text Layer").sourceRectAtTime().width;
thisComp.layer("My Text Layer").sourceRectAtTime().height;

Select sibling

Get sibling of current layer.

olderSibling = thisComp.layer(index - 1);
youngerSibling = thisComp.layer(index + 1);

Always center ancherpoint to viewport

Add this expression to the anchorpoint of the layer you want to center

s = thisLayer; // this used to point to the layer (in this case itself)
sTop = s.sourceRectAtTime().top; // spit out the top position property of the layer
sLeft = s.sourceRectAtTime().left; // spit out the left position property

sHeight = s.sourceRectAtTime().height; // spit out the height property of the layer
sWidth = s.sourceRectAtTime().width; // spit out the width property

sAnchorY = sTop + (sHeight/2); // calculate the Y-axis anchor from the top property added by half of the height of the layer
sAnchorX = sLeft + (sWidth/2); // more or less the same just for the horizontal or X-axis

[sAnchorX, sAnchorY] // actually putting all the end value to the value of the anchor point of the layer

Calucalte size of path

Note: this don't include tangents. And Bodymovin is not supporting es6+.

function pathBounds(points) {
	let minX = points[0][0], 
		minY = points[0][1], 
		maxX = points[0][0], 
		maxY = points[0][1];
	
	points.forEach(p => {
		minX = Math.min(minX, p[0]);
		maxX = Math.max(maxX, p[0]);
		minY = Math.min(minY, p[1]);
		maxY = Math.max(maxY, p[1]);
	});

	return {
		width: maxX - minX,
		height: maxY - minY
	}
}

const test = pathBounds([...thisComp.layer("TEST").content("face").content("mouth").content("lipLower").path.points(), ...thisComp.layer("TEST").content("face").content("mouth").content("lipUpper").path.points()]);

Typewriter smooth text center

TODO: Description

TRANSITION_DURATION = 0.5;
TIME_OFFSET = 0.25;

self = thisLayer;
sourceText = self.text.sourceText;
timeWithOffset = time + TIME_OFFSET;

x = value[0];

// If has keyframes
if (sourceText.numKeys > 0) {
  closestKeyframe = sourceText.nearestKey(timeWithOffset).index;

  // If keyframe is in future
  if (timeWithOffset < sourceText.key(closestKeyframe).time) {
    // Get to previous frame
    closestKeyframe--;
  }

  // If has close frame
  if (closestKeyframe > 0) {

    // Frame is not first
    if (closestKeyframe > 1) {

      prevKeyframeTime = sourceText.key(closestKeyframe - 1).time;
      currentKeyframeTime = sourceText.key(closestKeyframe).time;

      prevWidth = self.sourceRectAtTime(prevKeyframeTime, false).width;
      currentWidth = self.sourceRectAtTime(currentKeyframeTime,false).width;

      x = (x - ease(timeWithOffset, currentKeyframeTime, currentKeyframeTime + TRANSITION_DURATION, prevWidth, currentWidth)) / 2;
    } else {
      x = (x - self.sourceRectAtTime(timeWithOffset, false).width) / 2;
    }
  }
}

[x, value[1]]