Animated appearance of Photoshop layers - animation

Question

I'm working with a Photoshop document that has over 1,000 layers in it (1052, to be precise). The file itself is a collage and each layer is an individual image within that collage. So, when all layers are visible it's a complex collage of 1052 overlapping images. What I have been trying to do is create an animation of the collage assembly so that, for instance, layer 0 appears and then layer 1, layer 2, etc. and when each layer appears the previous layer also stays visible.
I have been able to make a frame animation, to which I've then added all other layers as frames but in this case the animation I create just makes each new frame/layer visible on its own, and making the previous layer(s) invisible. I've gone through the first several frames, manually keeping the previous layer/frame visible but I'm hoping there's a way to do this more automatically.
Is there an approach or a setting I'm missing that will allow me to automagically create this animation, keeping each frame visible as the next frame also becomes visible?

Answer 1

Basically, the premise of want you want is to go through all layers, switching on and off the viability as you go. Or switch them all off before you start, and get the code to loop through all the layers. Also as you are starting out, get rid of any groups, it'll just be easier. Make a copy of the psd without them if you have to.
In Photoshop scripting, the top most layer is 0. The next one below is 1 etc. It's easier to count backwards over the loop
for (var i = numOfLayers -1; i >= 0; i--)
{
// do stuff here
}
The visibility of each layer is controlled with:
theLayer.visible = true; // visible
thatLayer.visible = false; // not visible
So in short you'll have something like this:
// WITH ALL THE LAYERS VISIBILITY SWITCHED OFF TO START WITH!
// Switch off any dialog boxes
displayDialogs = DialogModes.NO; // OFF
// call the source document
var srcDoc = app.activeDocument;
// get the number of layers in the PSD
var numOfLayers = srcDoc.layers.length;
var myFolder = "D:\\temp\\";
// main loop
// ignore background
for (var i = numOfLayers -2; i >= 0 ; i--)
{
var docName = "image_" + i + ".jpg";
// get a reference to the layers as you go up
var thisLayer = srcDoc.layers[i];
thisLayer.visible = true;
// duplicate image into new document
duplicate_it(docName);
// active document is now the NEW one!
// flatten it
activeDocument.flatten();
jpeg_it(myFolder + docName, 12);
// close the image WITHOUT saving as we've just saved it
app.activeDocument.close(SaveOptions.DONOTSAVECHANGES);
// make the source document the active document
app.activeDocument = srcDoc;
// switch OFF the layer
thisLayer.visible = false;
}
// function DUPLICATE IT (str)
// --------------------------------------------------------
function duplicate_it(str)
{
// duplicate image into new document
if (arguments.length == 0) str = "temp";
var id428 = charIDToTypeID( "Dplc" );
var desc92 = new ActionDescriptor();
var id429 = charIDToTypeID( "null" );
var ref27 = new ActionReference();
var id430 = charIDToTypeID( "Dcmn" );
var id431 = charIDToTypeID( "Ordn" );
var id432 = charIDToTypeID( "Frst" );
ref27.putEnumerated( id430, id431, id432 );
desc92.putReference( id429, ref27 );
var id433 = charIDToTypeID( "Nm " );
desc92.putString( id433, str ); // name
executeAction( id428, desc92, DialogModes.NO );
}
// function JPEG IT (file path + file name, jpeg quality)
// ----------------------------------------------------------------
function jpeg_it(filePath, jpgQuality)
{
if(! jpgQuality) jpgQuality = 12;
// jpg file options
var jpgFile = new File(filePath);
jpgSaveOptions = new JPEGSaveOptions();
jpgSaveOptions.formatOptions = FormatOptions.OPTIMIZEDBASELINE;
jpgSaveOptions.embedColorProfile = true;
jpgSaveOptions.matte = MatteType.NONE;
jpgSaveOptions.quality = jpgQuality;
activeDocument.saveAs(jpgFile, jpgSaveOptions, true, Extension.LOWERCASE);
}