feat/screen filter: Add native screen-filter script with shaders, Rofi menu selector, and boot persistence

[anshifmonz]

Hey @mylinuxforwork! 👋

I put together a standalone screen filter utility for Hyprland and thought it would make a great addition to the dotfiles.

It allows users to toggle and cycle through GLSL screen shaders (such as Nightlight, Grayscale, Sepia, Invert Colors, and Blue-light filters) directly using keyboard shortcuts, an interactive Rofi menu, or CLI subcommands.

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Key Highlights

• Zero external dependencies: Uses native hyprctl shader calls under the hood (hl.config / keyword) — no need to install or configure hyprshade.
• State persistence across reboots: Remembers your active shader in cache and silently restores it on boot/login via autostart.lua.
• Auto-detects custom shaders: Automatically scans ~/.config/hypr/shaders/. If users drop any custom .frag or .glsl files in there, they will show up in the cycle and Rofi menu immediately.
• Compact Rofi picker: Uses ML4W's config-compact.rasi theme, pre-highlighting the active shader and allowing 1-click selection or disabling.
• Synchronous notifications: Gives clean desktop notifications with the active shader name.

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What's Included

1. dotfiles/.config/hypr/scripts/screen-filter.sh - Main executable script (cycle, --menu, restore, off, set <name>, status, list).
2. dotfiles/.config/hypr/shaders/ - Preset shader files (greyscale.frag, nightlight.frag, sepia.frag, invert-colors.glsl, and 25/50/75% blue-light GLSL filters).
3. dotfiles/.config/hypr/conf/keybindings/default.lua - Added default shortcuts.
4. dotfiles/.config/hypr/conf/autostart.lua - Added silent restore hook on Hyprland startup.

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Default Shortcuts

Keybinding	Action
SUPER + SHIFT + N	Cycle through available screen filters
SUPER + CTRL + N	Open the interactive Rofi filter menu
SUPER + ALT + N	Turn off / disable active screen filter

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Testing & Verification

Tested on the latest Hyprland build with ML4W config:

• Verified rotation cycle (None → Grayscale → Nightlight → Sepia → Invert → 25/50/75% blue-light → Disabled).
• Tested interactive Rofi menu selection and cancellation (Esc).
• Verified silent state persistence across reboots/reloads (screen-filter.sh restore).
• Verified keybindings appear properly in the keybinding search cheat sheet (SUPER + CTRL + K).
• Tested safe fallbacks if shaders are missing or if run outside Hyprland.

Demo

[eljejer]

Great addition indeed!

[mylinuxforwork]

This is absolutely great. Thank you so much.
Will be on vacation the next two weeks. Will test when I am back.