photoshop .jsx

#target photoshop

// the directory with displacement maps
var folderDisp = new Folder("D:/test");

// the directory with normal maps
var folderNorm = new Folder("D:/test");

// A file for color matching (color source)
var fileColorSource = new File("D:/test/disp_color_base/c.png");

// the directory for saving the results
var folderSave = new Folder("D:/test/output");

if (!folderDisp.exists || !folderNorm.exists || !fileColorSource.exists || !folderSave.exists) {
    alert("Verify that all paths are correct.");
    throw "Path error!";
}

// Prepare the log file
var logFile = new File(folderSave + "/log2.txt");
logFile.open("w");
logFile.writeln("=== LOG start: " + new Date().toString() + " ===");


// Find all displacement maps in the directory
var dispFiles = folderDisp.getFiles(function(f) {
    return f instanceof File && f.name.match(/_disp\.dds$/i);
});

if (dispFiles.length == 0) {
    alert("No _disp.dds files found.");
    throw "Cancelled";
}

// Processing
for (var i = 0; i < dispFiles.length; i++) {
    var fileDisp = dispFiles[i];

    try {
        // Extract the base name, e.g. a from a_disp.png
        var baseName = fileDisp.name.replace(/_disp\.dds$/i, "");

        // Find the normal map named e.g. a_n.dds
        var fileNorm = new File(folderNorm + "/" + baseName + "_n.dds");
        if (!fileNorm.exists) {
            logFile.writeln("Normal map not found: " + fileNorm.name);
            continue;
        }

        // Open color source
        var docColor = app.open(fileColorSource);
        // Open displacement map
        var docDisp = app.open(fileDisp);

        app.activeDocument = docDisp;

        // Do "Match colors": Image > Adjustments > Match Color
        var idmatchColor = stringIDToTypeID( "matchColor" );
        var desc = new ActionDescriptor();

        var src = new ActionReference();
        src.putIdentifier( charIDToTypeID( "Dcmn" ), docColor.id );
        desc.putReference( charIDToTypeID( "Srce" ), src );

        // luminance: default 100
        desc.putInteger(charIDToTypeID("LwCl"), 100);
        // color intensity: default 100
        desc.putInteger(charIDToTypeID("Clrs"), 100);
        // fade: default 0
        desc.putInteger(charIDToTypeID("Fzns"), 0);
        desc.putBoolean(charIDToTypeID("Ntrl"), false);

        executeAction( idmatchColor, desc, DialogModes.NO );

        // Switch to the displacement map and select all
        app.activeDocument = docDisp;
        docDisp.selection.selectAll();
        docDisp.selection.copy();

        // Open normal map
        var docNorm = app.open(fileNorm);

        // Switch to the normal map
        app.activeDocument = docNorm;

        // Go to the channels and select alpha
        var alphaChannel;
        try {
            alphaChannel = docNorm.channels.getByName("Alpha 1");
        } catch(e) {
            alphaChannel = docNorm.channels.add();
        }

        docNorm.activeChannels = [alphaChannel];
        docNorm.paste();

        // Save using the SaveAsDDS action (recorded before)
        app.doAction("SaveAsDDS", "DDS Actions");

        var tempSaveFile = new File(folderSave + "/TEMP.dds");
        // rename TEMP.dds → a_nh.dds
        var finalSaveFile = new File(folderSave + "/" + baseName + "_nh.dds");

        $.sleep(300);
        app.refresh();

        if (tempSaveFile.exists) {
            tempSaveFile.copy(finalSaveFile);
            tempSaveFile.remove(); // delete the temporary file
            logFile.writeln("Saved: " + finalSaveFile.name);
        } else {
        logFile.writeln("Error: TEMP.dds did not exist.");
        }

        //Close dolor source without saving (originals unchanged)
        docColor.close(SaveOptions.DONOTSAVECHANGES);
        // Close both maps without saving (originals unchanged)
        docDisp.close(SaveOptions.DONOTSAVECHANGES);
        docNorm.close(SaveOptions.DONOTSAVECHANGES);

    } catch(e) {
        logFile.writeln("Error in file: " + fileDisp.name + " - " + e.toString());
    }
}

logFile.writeln("=== LOG end: " + new Date().toString() + " ===");
logFile.close();

alert("Done! See the log: log2.txt");