%%%% **⚠️ 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. {{ :section:section-shadow-rule5-luminance_floor.webp?direct&400 }} * **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: {{ :section:section-shadow-alpha-80_100.webp?direct&500 }} ---- {{:ui:ui-color-hex-alpha_values.webp?200}} ^ Alpha cheat sheet\\ (most useful values) ^^^ ^ Color Picker\\ Hex: FB00FA37\\ {{:ui:ui-color-hex-alpha_values-base_fb00fa37.webp?50}} ^^^ | 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: {{:section:section-shadow_controlled_tests_1_-_7.webp?direct&200 }} {{:section:section-shadow_test_parameters.webp?direct&700 }} \\ \\ \\ \\ ---- ==== Shadow Contrast Summary ==== {{tablelayout?colwidth="150px,150px,150px,150"&rowsHeaderSource=auto&float=center}} ^ **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 [[:howto:howto-shadows-dark_background|this hack]] to overcome the failure. | {{page>site:site-footer-comment_feedback_block}}