Imagemagick: compose 2 images where 1 wraps the other - image-processing

Question

I want to make a wrapping image or gif that when composed with a different image will wrap it like the wrapping image.
For example combining these two images:
Would yield this image
I don't want an imagemagick command that does this specific movement of pixels because then it wouldn't be modular.

Answer 1

Here is one way in Imagemagick using the -roll function. But unfortunately it does not use percent. So I have to do a separate computation in IM 6 to convert percent to pixels. In IM 7 it could be done in one command apart from setting the pct overlap and split.
Here I cut the image into 3 sections (33% each, though different amounts could be used). And then roll the middle sections by 33% to the right with wrap around.
IM 6
pct=33
rollx=`convert palmtree.png -format "%[fx:round($pct*w/100)]" info:`
convert palmtree.png \( -clone 0 -gravity north -crop 100%x$pct%+0+0 +repage \) \( -clone 0 -gravity center -crop 100%x$pct%+0+0 +repage -roll +${rollx}+0 \) \( -clone 0 -gravity south -crop 100%x$pct%+0+0 +repage \) -delete 0 -append result.png
IM 7
pct=33
magick palmtree.png -set option:rollx "%[fx:round($pct*w/100)]" \( -clone 0 -gravity north -crop 100%x$pct%+0+0 +repage \) \( -clone 0 -gravity center -crop 100%x$pct%+0+0 +repage -roll +[rollx]+0 \) \( -clone 0 -gravity south -crop 100%x$pct%+0+0 +repage \) -delete 0 -append result.png
If you do not want 33% for all, then change the pct to whatever percent you want for each part and for the roll as desired. If you want to use multiple images, then replace each -clone with the actual image you want.