Photoshop - show the same file in two separate windows, each different layer comp

Question

Is it possible to show the same photoshop file in two separate windows, each with a different layer comp?

Answer 1

So I wrote a script that should get pretty close to what you are after.

If you're not familiar with using scripts, I'm sure there are many sources if you google: "how to run scripts in photoshop" or something. Though it may be good to know that you can: 1. set a shortcut to run a script 2. run a script from an Action 3. run it from the File > Scripts... menu 4. run it using third party applications (like I'm doing in the gif). The script was tested in Photoshop CC 2019, so there is a chance it won't work in anything older...

What you don't see in the gif is that this comparison image is actually a new document. I just keep closing it and running the script again. The gif is a bit hectic, I know, but I had to make sure the filesize is small enough to upload here.

// Version 1.1.
// Compare Selected Comps.jsx
// https://gist.github.com/joonaspaakko/adbe208a867f8681afa86032f91f5099?ts=2

// #########
// Changelog
// #########

// v.1.1.
// - Tested in Photoshop CC 2019
// - Added a fallback for when less than 2 layer comps are selected, in which case all layer comps are pushed to the comparison document.
// - Fixed the border issue.
// - Fixed the issue where comp gets fused with the comparison document background.

// v.1.0.
// - First Version
// - Tested in Photoshop CC 2019
// - Known issues:
//      - The script adds a border around the final comp layer in order to divide the comp layers a bit. If the comp doesn't have a solid background, the stroke will do weird things.
//      - The first comp gets fused with the background of the comparison document in some situations...

#target photoshop

var startCompare = false;
var maxHorizontal = 1;

if ( app.documents.length > 0 ) init();

function init() {

    var rulerUnits = app.preferences.rulerUnits;
    app.preferences.rulerUnits = Units.PIXELS;

    var doc = app.activeDocument;

    // Duplicate current document
    var tempDoc = doc.duplicate( (doc.name + ' (Comparison)') );

    // Check layer comp selection.length
    // Get layer comps
    var layerComps = tempDoc.layerComps;
    var selectedComps = [];
    var leftOverComps = [];
    // Go through every comp
    for ( var i=0; i < layerComps.length; i++ ) {
        var comp = layerComps[ i ];
        // If comp is selected...
        if ( comp.selected ) {
            selectedComps.push( comp );
        }
        else {
            leftOverComps.push( comp );
        }
    }

    // If more than one comp is selected...
    // Remove all leftover layer comps
    if ( selectedComps.length > 1 ) {

        // Go through every comp
        for ( var i=0; i < leftOverComps.length; i++ ) {
            var comp = leftOverComps[ i ];
            comp.remove();
        }

    }

    dialog( tempDoc.layerComps.length );

    if ( !startCompare ) {
    // tempDoc.close( SaveOptions.DONOTSAVECHANGES );
    }
    else if ( startCompare ) {

        var tempDocsCollection = [];
        // Get layer comps again...
        var layerComps = tempDoc.layerComps;
        var selectedCompsLength = layerComps.length;
        // Go through every comp
        for ( var i=0; i < selectedCompsLength; i++ ) {

            var comp = layerComps[ i ];
            comp.apply();
            var thisCompDoc = tempDoc.duplicate( comp.name, true);
            thisCompDoc.flatten();
            addBlackBorder();
            tempDocsCollection.push( thisCompDoc );
            app.activeDocument = tempDoc;

        }

        // Get ready to receive compsies
        // Scrub the temp document clean...
        tempDoc.flatten();
        whiteFill();

        // New size to fit the border
        tempDoc.resizeCanvas( (tempDoc.width + 1), (tempDoc.height + 1), AnchorPosition.TOPLEFT );

        var tempDocWidth = tempDoc.width;
        var tempDocHeight = tempDoc.height;

        // Find out how many rows are needed
        var columns = maxHorizontal;
        var rows = 0;
        var equalizer = 1;
        for ( var i = 0; i < selectedCompsLength; i++ ) {
            if ( equalizer == 1 ) {
                rows = rows+1;
            }
            equalizer = equalizer == columns ? 1 : equalizer + 1;
        }

        var newWidth = tempDocWidth * columns;
        var newHeight = tempDocHeight * rows;
        tempDoc.resizeCanvas( newWidth, newHeight, AnchorPosition.TOPLEFT );

        // Go through every comp document
        var cumulativeWidth = 0;
        var cumulativeHeight = 0;
        var equalizer = 1;
        for ( var i=0; i < tempDocsCollection.length; i++ ) {

            var compDoc = tempDocsCollection[ i ];
            app.activeDocument = compDoc;
            compLayerName = compDoc.name;

            // Duplicate comp document back to the tempdoc as a single layer...
            var compLayer = compDoc.activeLayer.duplicate( tempDoc, ElementPlacement.PLACEATEND );
            compDoc.close( SaveOptions.DONOTSAVECHANGES );
            app.activeDocument = tempDoc;
            compLayer.name = compLayerName;

            // Move comp layers side by side
            compLayer.translate( cumulativeWidth, cumulativeHeight );

            cumulativeWidth  = ( equalizer == columns ) ? 0 : cumulativeWidth  + tempDocWidth;
            cumulativeHeight = ( equalizer == columns ) ? (cumulativeHeight + tempDocHeight) : cumulativeHeight;
            equalizer = equalizer == columns ? 1 : equalizer + 1;
        }

    }

  app.preferences.rulerUnits = rulerUnits;

}

function whiteFill() {

  function cTID(s) { return app.charIDToTypeID(s); };
  function sTID(s) { return app.stringIDToTypeID(s); };

  var desc419 = new ActionDescriptor();
  desc419.putEnumerated( cTID('Usng'), cTID('FlCn'), cTID('Wht ') );
  desc419.putUnitDouble( cTID('Opct'), cTID('#Prc'), 100.000000 );
  desc419.putEnumerated( cTID('Md  '), cTID('BlnM'), cTID('Nrml') );
  executeAction( cTID('Fl  '), desc419, DialogModes.NO );

}

function selectAllLayers() {

    // Makes background layer a normal layer.
    // Otherwise it wouldn't be selected in the next step.
    var firstLayer = app.activeDocument.layers[ app.activeDocument.layers.length - 1 ];
    if ( firstLayer.isBackgroundLayer ) firstLayer.isBackgroundLayer = false;

    // Select all layers...
    var actionDescriptor = new ActionDescriptor();
    var actionReference = new ActionReference();
    actionReference.putEnumerated( charIDToTypeID( "Lyr " ), charIDToTypeID( "Ordn" ), charIDToTypeID( "Trgt" ) );
    actionDescriptor.putReference( charIDToTypeID( "null" ), actionReference );
    executeAction( stringIDToTypeID( "selectAllLayers" ), actionDescriptor, DialogModes.NO );

}

function addBlackBorder() {

  function cTID(s) { return app.charIDToTypeID(s); };
  function sTID(s) { return app.stringIDToTypeID(s); };

  var desc97 = new ActionDescriptor();
  desc97.putBoolean( cTID('Rltv'), true );
  desc97.putUnitDouble( cTID('Wdth'), cTID('#Pxl'), 2.000000 );
  desc97.putUnitDouble( cTID('Hght'), cTID('#Pxl'), 2.000000 );
  desc97.putEnumerated( cTID('Hrzn'), cTID('HrzL'), cTID('Cntr') );
  desc97.putEnumerated( cTID('Vrtc'), cTID('VrtL'), cTID('Cntr') );
  desc97.putEnumerated( sTID('canvasExtensionColorType'), sTID('canvasExtensionColorType'), cTID('Clr ') );
      var desc98 = new ActionDescriptor();
      desc98.putUnitDouble( cTID('H   '), cTID('#Ang'), 0.000000 );
      desc98.putDouble( cTID('Strt'), 0.000000 );
      desc98.putDouble( cTID('Brgh'), 0.000000 );
  desc97.putObject( sTID('canvasExtensionColor'), cTID('HSBC'), desc98 );
  executeAction( cTID('CnvS'), desc97, DialogModes.NO );

}

function dialog( compsLength ) {

    /*
    Code for Import https://scriptui.joonas.me — (Triple click to select):
    {"activeId":0,"items":{"item-0":{"id":0,"type":"Dialog","parentId":false,"style":{"varName":null,"text":"Compare Selected Comps.jsx","preferredSize":[0,0],"margins":29,"orientation":"row","spacing":10,"alignChildren":["right","center"]}},"item-1":{"id":1,"type":"EditText","parentId":0,"style":{"varName":null,"text":"4","preferredSize":[52,0],"alignment":null,"helpTip":null}},"item-2":{"id":2,"type":"StaticText","parentId":0,"style":{"varName":null,"text":"Max comps side by side:","justify":"left","preferredSize":[0,0],"alignment":null,"helpTip":null}},"item-5":{"id":5,"type":"Button","parentId":0,"style":{"varName":null,"text":"Cancel","justify":"center","preferredSize":[0,0],"alignment":null,"helpTip":null}},"item-6":{"id":6,"type":"Button","parentId":0,"style":{"varName":null,"text":"Compare","justify":"center","preferredSize":[0,0],"alignment":null,"helpTip":null}}},"order":[0,2,1,6,5]}
    */

    // DIALOG
    // ======
    var dialog = new Window("dialog");
        dialog.text = "Compare Selected Comps.jsx";
        dialog.orientation = "row";
        dialog.alignChildren = ["right","center"];
        dialog.spacing = 10;
        dialog.margins = 29;

    var statictext1 = dialog.add("statictext");
        statictext1.text = "Max comps side by side:";

    var edittext1 = dialog.add("edittext");
        edittext1.text = "4";
        edittext1.preferredSize.width = 52;

    var button1 = dialog.add("button", undefined, undefined, {name:"ok"});
            button1.text = "Compare";
            button1.justify = "center";

    var button2 = dialog.add("button", undefined, undefined, {name:"cancel"});
            button2.text = "Cancel";
            button2.justify = "center";

    // Customization

    edittext1.text = compsLength;
    edittext1.active = true;

  button1.onClick = function() {
     startCompare = true;
     maxHorizontal = parseInt( edittext1.text, 10);
     dlg.close();
  }

  button2.onClick = function() {
    dlg.close();
  }

  dialog.show();


}