I’m a scripting newb, however it does appear to be possible to find the position of a placed guide, so what you wan’t should be possible, presuming that there is only one guide existing:
How to get exact position of a ruler guide in Photoshop? - Super User
EDIT:
The following is my fledgling start/prototype, presuming only a single guide:
var savedRuler = app.preferences.rulerUnits; //store the current ruler units
app.preferences.rulerUnits = Units.CM; //set the ruler units to CM
var guidePos = app.activeDocument.guides[0] //retrieve the existing guide
activeDocument.guides.add(Direction.HORIZONTAL, guidePos.coordinate.value + 1); //add new guide +1cm from existing guide
activeDocument.guides.add(Direction.HORIZONTAL, guidePos.coordinate.value - 1); //add new guide -1cm from existing guide
app.preferences.rulerUnits = savedRuler //restore the original ruler units
This simple code will add two new horizontal guides, 1cm above and below the existing guide. I’m sure that lines 04 + 05 can be refined into a single line (the syntax currently eludes me).
If you start with a single guide, and add three more, are these simply added at a positive or negative distance from the original, up or down the height of the image?
What you need is a GUI where you can enter in N number of guides, which is beyond my current knowledge and skillset (I was lucky to make it this far). Unfortunately this code is not much better than your current action… However I hope that this helps you to get the ball rolling, I’m looking forward to what the experts come up with!
AdChoices