ImageMagick montage natural file order - imagemagick

Question

I am trying to use the ImageMagick montage feature to combine chunks of maps from a game. My issue is that the game's original files are naturally ordered like
part1.png
part2.png
...
part10.png
ImageMagick reads this and will tile part10.png after part1.png. Is there a flag/option to tell IM to read the directory the way I want it to? This is a live code sample of what I'm doing.
montage \
-alpha on \
-background none \
-mode concatenate \
-tile x{$grid} \
-mattecolor none \
{$input_dir}/*.png \
{$output_file}

Answer 1

You can possibly use sort -g (that's general numeric sort) to get what you want.
Test:
Create 12 dummy files:
for i in {1.12} ; do touch ${i}.txt ; done
List the files:
ls -1 *.txt
1.txt
10.txt
11.txt
12.txt
2.txt
3.txt
4.txt
5.txt
6.txt
7.txt
8.txt
9.txt
Use sort -g to list them in different order:
ls -1 *.txt | sort -g
1.txt
2.txt
3.txt
4.txt
5.txt
6.txt
7.txt
8.txt
9.txt
10.txt
11.txt
12.txt
Real Life:
Now apply this to solve your problem:
montage \
-alpha on \
-background none \
-mode concatenate \
-tile x{$grid} \
-mattecolor none \
$(ls -1 {$input_dir}/*.png | sort -g) \
{$output_file}
If your $input_dir name doesn't contain any spaces, this should work flawlessly.