Hi Arthesian, I know how it sounds, it sounds ridiculous but I have good argument.
For now we have background and foreground and that is usually enought.
However middleground would help in rendered anime arts (yeah anime girls).
For example:
• background: let say we have static image or random images, like 130 random images
• foregraound: its rendered anime girl.
If we put random colors effect on foreground then you can predict what would happen, she will get ugly skin color but we would like to randomize only her hair or clouth color. It can be easy fixed with middleground image in example we put her hair or cloth in foreground but whole girl in middleground. Then only hair or cloth will get random colors. For anime girls are very important such attributes like hair color and eye color since this is such art style.
For example right now I've such setup:
• background: I've static image (because I can't use randomized photo or I would need to change about 130 photos) with edited pasted girl's outfit.
• foreground: I've girl without her outfit, I cut it off
• effect: background is changing colors including girl'ss outfit while girl don't have any color effect (this is live preview https://cdn.discordapp.com/attachments/165220044366807040/853583556051599370/2021-06-13_12-34-19.mp4 yeah hosted on Discord since I showed it to friends, no virus).
So te goal would be:
Have separate background, so it can be anything like always, random images, video or static image, but not edited.
• Have middleground as addon in case it would be ever needed
• Have foreground like always
Of course middleground would need own set of effects, but they can be exactly same like for foreground.
I wonder how much additional work it would requirie. If its too much work then let's forgot about it.
Same thing posted here:
https://bitbucket.org/Arthesian/wallpaper-module-visualizer/issues/110/middleground-image-suggestion