The inspiration was a YouTube video, I've watched the beginning and though to myself that this cannot be that hard to implement.
Of course it is not without usage, I will prepare the app to be hooked in Hyprland to launch the current photo stored in clipboard.

Requirements

SDL3

Installations

As of now the only like-indented working implementation is for macOS. Wayland ignores the desired window states (resize, position).

macOS

brew install sdl3
clone this repo and navigate into it
gcc SimpleImageViewer.c -o SimpleImageViewer -Wall -Werror $(pkg-config --cflags --libs sdl3) or with clang
additional compiler arguments for ide: -I/opt/homebrew/include -L/opt/homebrew/lib -Wl,-rpath,/opt/homebrew/lib -lSDL3

Linux

sudo pacman -S sdl3 --noconfirm
gcc SimpleImageViewer.c -o SimpleImageViewer -Wall -Werror $(pkg-config --cflags --libs sdl3) -lm or with clang
when using Hyprland, move the scripts folder into your ~/.config/hypr/
in simple-image-viewer-clipboard.sh: set viewer, I placed my binary beside this script
move the hypr_simpleimageviewer.lua file into ~/.config/hypr/
replace [USER] with your user
add require(hypr_simpleimageviewer) at the top of your Hyprland config

Usage

If installed via Hyprland binding, SUPER + I is used to parse a file from clipboard (path or binary) as argument into SimpleImageViewer.
Via commandline ./SimpleImageViewer [path_to_image].

Mouse-/Keybinds:

Close: ESC, Enter, Space
Move image: press right mouse button and drag
Resize image: scroll mouse wheel