exchange precomps in multiple comps (1500 comps)

[Meng Zhiqun]

Hi Gerald,

When you say you need to change the precomp layer, may I know what exactly do u need changed on that layer?

[Gerald Gutberlet]

I will try to explain I make let say 1 hundred copys of my first comp wich has a control precomp layer and a Baseshape precomp layer.

all the comp are named 0,1,2,3,4,5,6,7,8,9 and so on

and I need to replace the Baseshape precomp in comp1 with the comp 0 and in comp 2 with comp 1 and in comp 3 with comp2 and in comp 4 with comp 3 and so on.

maybe my first test will help.

Reactiondiffusion_0-30.aep 3 MB After Effects Project Files - Click to view

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[Meng Zhiqun]

You can try this! For this to work, you need to have the following created.
“diffusion” layer, “0” layer, “Master” layer.
I’ve also parented the new comps to the folder that you are already using, “Unbenannt 1”.

var totalCompToCreate = 100;//Change this number to whatever number you like.
var proj = app.project;
var itemTotal = proj.numItems;
var projComp = proj.activeItem;
for (var i=itemTotal; i > 0; i--){
    var curItem = proj.item(i);
    if(curItem.name == "Unbenannt 1"){
        if(curItem.typeName == "Folder"){
            var compFolder = curItem;
        }
    }
    if(curItem.name == "diffusion"){
        if(curItem.typeName == "Composition"){
            var diffComp = curItem;
        }
    }
    if(curItem.name == "0"){
        if(curItem.typeName == "Composition"){
            var indexComp = curItem;
        }
    }
    if(curItem.name == "Master"){
        if(curItem.typeName == "Composition"){
            var masterComp = curItem;
        }
    }
}
function createComps(){
    for (var i=1;i<=totalCompToCreate;i++){
        var newComp = proj.items.addComp(i, indexComp.width, indexComp.height, indexComp.pixelAspect, indexComp.duration, indexComp.frameRate);
        newComp.parentFolder = compFolder;
        newComp.layers.add(indexComp);
        var diffLay = newComp.layers.add(diffComp);
        diffLay.collapseTransformation = true;
        var masterNewLayer = masterComp.layers.add(newComp);
        masterNewLayer.startTime = i/masterComp.frameRate;
        indexComp = newComp;
    }
}
app.beginUndoGroup("createComps");
createComps();
app.endUndoGroup();

[Meng Zhiqun]

Also, keep in mind that with this script, you can’t have any items with the same name. To prevent problems caused by the same name, more checks need to be added to this script too.

[Gerald Gutberlet]

many many thanks Meng i will give it a try and will tell you how it worked. I am at 300 comps by hand but as i said maybe i need 3000 comps or more, so this will be verry helpfull.

Greetings from Germany🤩

[Meng Zhiqun]

Welcome! Hope this helps! Greetings from Singapore! Just a note, you need to delete whatever you have done for the script to work since it starts from layer”1″. So whatever work you have done, might be wasted.
It took a few seconds for my machine to produce 300 comps, and I’m already on intel i9 10900k with 64gb ram. If you are looking at more than that, I hope your machine can take the hit! 😀

[Gerald Gutberlet]

Hi Meng dont worry about the work that if have done no problems nothing is ever realy wasted.

I tried to run your script but i get an error massage in AE. line 58 undefiened is not an object

maybe because i dont have the AEscript editor installed dont know but thanks for trying.

AND the script actualy dont has to generate or copy new Comps, that is easyly done by Hand.

it just would have to replace the precomps as i have discribed above, if that is possible

Bildschirmfoto-2021-11-01-um-13.23.25.png 146 KB Image File - Click to view

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[Gerald Gutberlet]

Oh and i am on a Mac OS Big SUR

[Gerald Gutberlet]

But i have VS Code on my Mac ??? With wich i stored your code as JSX but as i said i get the error message

[Meng Zhiqun]

Hey Gerald. My script only has 47 lines, are you sure that’s my code? Alternatively, why dont you try giving this a try? I saved it as a .jsx for you, you can run it via, File, Scripts, Run script file.