Ethereal — Live Wallpaper Engine

"Touch the Glitch."

An OpenGL ES live wallpaper that renders lo-fi glitch aesthetics in real time on your Android home screen.

📱 Overview

Ethereal is an Android live wallpaper built with Kotlin and OpenGL ES 2.0.

Rather than looping a video, every frame is rendered on the GPU through custom GLSL shaders. Scanlines, sporadic glitch bursts, and drifting particles are layered over curated background artwork to create a calm, lo-fi atmosphere that reacts to touch and device motion.

✨ Key Features

1. Three-Layer GPU Rendering

Each frame composites three independent shader programs.

• Background: Texture sampling with scanlines, RGB channel shift, and horizontal band displacement.
• Glitch Overlay: Block noise, scanline tearing, and touch-driven ripple distortion.
• Particles: GL_POINTS batched by color, with gravity-driven motion.

2. Per-Theme Motion Profiles

Every theme carries its own parameters, so the same shaders produce distinctly different moods.

• glitchIntensity — strength of glitch and RGB shift
• particleDensity — spawn rate and burst size
• scanlineStrength — scanline contrast

Quiet night scenes sit near 0.15–0.2 so the effects never overpower the image, while abstract themes push past 0.7.

3. Sensor & Touch Reactivity

• Touch Ignition: Particle bursts spawn at the touch point; the glitch shader adds a localized ripple.
• Accelerometer Drift: Particles respond to device tilt through the gravity vector.
• Parallax: Home screen scroll offsets shift the background texture.

4. Charge Scan

Plugging in a charger triggers a single scan band that sweeps from the bottom of the screen to the top over two seconds, then disappears. ACTION_POWER_CONNECTED is received at runtime and passed to the glitch shader as a progress uniform — no extra layer, no persistent animation.

🛠 Technical Highlights

• Manual EGL Management: WallpaperService.Engine cannot host a GLSurfaceView, so the EGL14 context, surface, and lifecycle are handled directly.
• Single GL Thread: A dedicated single-thread dispatcher serializes all GL work — context creation, texture upload, draw calls, and teardown — through coroutines.
• Shaders as Resources: GLSL lives in res/raw/*.glsl and is compiled at theme-switch time, keeping rendering logic out of Kotlin.
• Live Theme Switching: A SharedPreferences listener applies theme changes the moment they are selected, with no service restart.
• Scaled Theme List: As the catalog grew past twenty entries, the picker moved to LazyColumn so only visible rows are composed, and every theme gained a dedicated 298×660 thumbnail instead of decoding its full-size background for an 84dp cell.

📂 Architecture

com.gadgeski.ethereal
├── EtherealWallpaperService.kt   # Service, EGL lifecycle, draw loop
├── MainActivity.kt               # Entry screen
├── opengl/
│   ├── EglHelper.kt              # EGL14 context & surface management
│   ├── ShaderHelper.kt           # GLSL compile & link
│   └── TextureHelper.kt          # Drawable → GL texture
├── renderer/
│   └── EtherealGLRenderer.kt     # Three-layer render pipeline
└── settings/
    ├── WallpaperTheme.kt         # Theme definitions & parameters
    └── SettingsActivity.kt       # Theme picker (Compose)

res/raw/
├── bg_vertex.glsl / bg_fragment.glsl
├── glitch_vertex.glsl / glitch_fragment.glsl
└── particle_vertex.glsl / particle_fragment.glsl

🎨 Themes

Themes are grouped into four series. Each shares a treatment rather than a subject — the processing stays consistent while the source material varies.

Abstract

Saturated blues and engineered textures. Halftone dots, wood grain, poured paint, aquarium glass. The original set, and the most openly synthetic.

Azure Sky · Rainy Window · Chill Aquarium · Indigo Grain · Cobalt Paint · Halftone Curve · Mint Wave

Fracture

A photograph cut into stepped blocks, half of it withheld. Two pieces that share a composition and differ only in what lies behind the cut.

Mono Fracture · Azure Fracture

Night

Monochrome scenes after dark, built on absence rather than color. A street, a window, a hillside, a train — lit by whatever happens to still be on.

Quiet Street · Distant Lights · Window Vigil · Lone Lamp · Crossroad Dusk · Hillside View · Balcony Night · Last Train · After Rain · Canyon Sky · Station Below · Fog Valley

Warm

The counterweight. Amber, rose, and gold at the edges of the day, with enough shadow left in the lower frame to keep icons legible.

Condensation · Light Leak · Tatami Room · Seaside Shelter · Coastal Dusk · Porch Sunset · Golden Field · Harbor Window · Wet Lane · Signal Dusk · Blurred Canyon

🚀 Getting Started

1. Clone the repository.

   git clone https://github.com/gadgeski/Ethereal.git

2. Open in Android Studio.

3. Build and run on a physical device (live wallpapers are unreliable on emulators).

4. Select Ethereal from the wallpaper picker.

🎭 Design Philosophy

• Aesthetic: Lo-fi / glitch — noise as texture, never as spectacle.
• Composition: Light is earned by darkness around it. Most themes hold the lower third back so the home screen stays readable.
• Principle: Glitch is seasoning. If it announces itself, the atmosphere is already broken.

🔧 Requirements

• Android 11 (API 30) or higher
• OpenGL ES 2.0 support