I use ZSH to open several images with Preview on top of each other, but how to offset the Preview windows?

Question

When I use ZSH to open multiple images using Preview programmatically, I get each Preview image stacked on top of each other. There is no way for the user to tell how many windows are piled on top of each other.

Code example:

# Loop through array of screenshot names
    for screenImage in $screenShotsSaved; do
        open -a preview $screenImage
    done

The result looks like this:

I would prefer to have each of the Preview windows offset "a little" so each Preview window can be seen. Something like this:

Any ideas on how to offset these previewed images programmatically from ZSH?

I have tried using "-geometry" option (where the +0-30 is just an example):

open -a preview $screenImage -geometry +0-30

But the geometry argument gets interpreted as an image -which in turn generates an error:

The file /Users/ronfred/+0-30 does not exist.

I have tried including this applescript snippet into my zsh script to move each preview window using this code (where {1, 30} is just an example):

open -a preview $screenImage 
 osascript \
 -e 'tell application "Preview"' \
 -e 'set position of front window to {1, 30}' \
 -e 'end tell'

But this script resulted in this error:

25:67: execution error: Preview got an error: Can’t make position of window 1 into type reference. (-1700)

Answer 1

I created a test case to demonstrate solution using AppleScript.

#!/bin/zsh

# Test case: 
#   Capture screen images with screencapture,
#   then display each of them with an increasing offset. 
#   Script calls builtin functions - screencapture, preview, applescript.
#   

declare -i offset_x=10
declare -i offset_y=10
max_images=4
firstPreview=true
# Include a safe base file name for auto-crearted images.
test_image="./base_image_4968f9bb-5007-47a6-92d5-bdcd1a81e4_"


# Create and display some test images using screencapture and preview.
for ((i=1; i<=$max_images; i++)); do

    # Create test image if not already available.
    if [[ ! -e $test_image$i.png ]]; then
        screencapture -R 100,100,50,50 $test_image$i.png
    fi

    # Open each test image in upper left corner of display
    open -a preview $test_image$i.png

    # Avoid system event error (-1719) on first reference to "Preview" 
    # in applescript.
    # Consider using applescript repeat feature with "System Events"
    if $firstPreview; then
        sleep 1
        firstPreview=false
    fi

    # Cascade/nudge each previewed image down and to left using applescript.
    osascript -  "$offset_x" "$offset_y"  <<EOF
    on run argv 
    tell application "System Events"
        tell process "Preview"
        set position of front window to {item 1 of argv, item 2 of argv}
        end tell
    end tell
    end run
EOF

    offset_x+=40
    offset_y+=40

done