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⚠️ v4.0 UI Transition Notice - In Process: The release of Total Launcher v4.0 has introduced significant user interface changes. Please note that this page does not yet reflect these updates. The new layout paths, folds, and visual maps are currently being compiled and will be deployed shortly.


Shadows: Rule 5 - The Contrast Wall

This is a visibility rule … “If a shadow isn't seen … there is a contrast wall!”

In the Android rendering engine, shadows are not solid objects; but instead are mathematical blurs applied to the background. For a shadow to be visible, there must be a significant difference in brightness (Value) between the shadow and the wallpaper.

The Luminance Floor

The “eye” recognizes brightness as the subjective value of a measure of luminance. On dark backgrounds (a luminance value < 20%, such as OLED black), low-alpha shadows effectively “sink” into the darkness and disappear. The “eye” does not register them.

  • The Problem: When a light color is spread over a large radius, the “Luminance Density” drops. A 20% white shadow spread over a 50px radius becomes so thin it is invisible to the human eye.

  • The Solution: To stay visible on dark themes, use a Higher Alpha (80%+) or Solid Colors.

Alpha Visualized

Shown here are reference characters of the Alpha's for “AA”RRGGBB:


Alpha cheat sheet
(most useful values)
Color Picker
Hex: FB00FA37
Alpha Transparency Glass Effect
FF 100% opaque Solid
E6 90%
CC 80% Almost solid
B3 70%
99 60%
80 50% Heavy glass
66 40%
4D 30% Medium glass
33 20% Light glass
1A 10% Very light glass
00 0% transparent

Alpha Test Results

The images below show shadows (or lack of a shadow) when using the noted shadow options in the launcher's shadow dialog:




Shadow Contrast Summary

Summary:
Background Type Shadow Strategy Recommended Alpha Result
Light Wallpaper Dark/Black Shadow 20% – 50% (`40` to `80`) Success: Soft, realistic depth.
Dark Wallpaper White/Light Glow 80% – 100% (`CC` to `FF`) Success: A visible “Halo” or “Ambient Lift.”
Dark Wallpaper Any Shadow Color Below 50% (`80`) FAILURE: Shadow vanishes into the background noise. See this hack to overcome the failure.

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