Expressions used in video tutorial on Premiere Pro driven After Effects templates on PremierePro.net.

http://premierepro.net/after-effects/premiere-pro-driven-after-effects-templates


I owe a lot to these people, who know a lot more about expressions than me

  Kati Haapamäki, Valve Media Oy, Finland
  Dan Ebberts, MotionScript.com
  Evan Abrams, EvanAbrams.com/


Useful expressions:

  sourceRectAtTime() 
    returns the width and height of text and shape layers. 
  parseFloat
    looks for numbers
  toLowerCase
    converts text to all lower case

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Expression used to control height of Shape Layer (Bar) based on a text from a text layer named "Bar 1 Size".

  Apply to Scale parameter of the Shape Layer 

y = parseFloat(thisComp.layer("Bar 1 Size").text.sourceText);
[100, y]

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Expression to control Opacity (on/off) for a layer based on the text from a text layer named "Align". 

  Apply to the Opacity parameter of the layer.

If it's R, upper or lower case, the opacity will be whatever it's set at. If it's not, the Opacity will be set to zero.

input = thisComp.layer("Align").text.sourceText.toLowerCase();
if (input == "r") {
  value
}else {
  0
}

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Expression to make Shape Layer size adjust according to the size of a text layer named "Credit".

  Apply to Size parameter of Rectangle Path in shape layer.

s=thisComp.layer("Credit");
padding=250;
y=120;
x=s.sourceRectAtTime().width+padding;
[x,y]

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Expression to make sure a Shape Layer scales from the upper left corner.

  Apply to Position parameter of Rectangle Path in shape layer.

content("Rectangle 1").content("Rectangle Path 1").size/2

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Expression to place a logo based on width of Matte layer named "Matte"

  Apply to Posistion parameter of Logo layer

x=thisComp.layer(“Matte”).sourceRectAtTime(time,true).width;
gap=30;
y=956;
[x+gap, y]

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