In graphics programming, shadows are often created using a Gaussian Blur. To create this effect, the software looks at a single pixel and then looks at the pixels surrounding it within a certain distance to decide how to blend them.The “Radius” is that distance.
Specific Total Launcher values translate to what is seen on the screen:
| Value | Visual Result | What’s Happening Mathematically |
|---|---|---|
| 0 | Invisible | The software essentially “turns off” the shadow calculation. |
| 1 – 5 | Sharp Drop Shadow | The blur distance is so small that the edges remain crisp. It looks like a hard sticker or a “cutout” effect. |
| 6 – 20 | Soft Shadow | The edges begin to plume outward. This mimics a light source that is relatively close to the object. |
| 50+ | Diffuse/Floating | The shadow spreads very far and becomes very faint, making the object look like it's hovering high above the background. |
Total Launcher utilizes the Android system's graphics engine to render shadows, typically using a Gaussian Blur algorithm.
When a radius is set the software creates a “sampling window” (a kernel). If the radius is 5, the software looks at every pixel and averages its color with the pixels 5 spaces away in every direction.
Technically, the “Radius” is simulating the Umbra and Penumbra:
Higher radius values require more processing power because the “sampling window” grows exponentially.
On older devices, very high shadow radii across many items can occasionally impact scrolling smoothness.