fancy_overlay

Flutter package that provides a collection of stunning, customizable overlays to enhance your app's visual appeal. With a convenient API for adding overlays, it includes effects like VHS glitch, pixel noise, real backdrop pixelation, falling widgets, vignette, and more. Designed for flexibility, the package allows for unique configurations and supports easy expansion with new overlays in the future.

Features

• FallingWidgetsOverlay()

  • Highly customizable snowfall animation or any other falling widgets.

  • Control properties like vertical and horizontal speed, scale, rotation, opacity, animation duration.

  • Perfect for adding a festive snowfall effect or any themed animation.

       

• VhsOverlay()

  • Applies a Heavy VHS-on-CRT backdrop effect with curvature, RGB separation, tracking distortion, procedural noise, scanlines, flicker, and vignette.

  • Choose VhsOverlayConfig.mild(), .balanced(), or .heavy(), then use copyWith to tune individual signal controls.

  • Uses one shader image-filter pass when supported and automatically falls back to a portable painter approximation on other renderers.

  • Call VhsOverlay.precacheShader() before first use to reduce activation latency.

  • Compatibility: True curvature, backdrop distortion, and RGB separation require ImageFilter.isShaderFilterSupported. On other renderers, VhsOverlay keeps its visual character with a portable fallback that draws animated scanlines, noise, tracking, flicker, and vignette. In the same situation, VhsOverlay.precacheShader() completes without loading a shader program.

     

• PixelNoiseOverlay()

  • Draw animated square pixel noise over your app with adjustable pixel sizes, color schemes, opacity, and noise frequency.

     

• PixelizeOverlay()

  • Pixelate the already rendered backdrop behind the overlay with a configurable pixelSize.

  • Uses a shader-backed backdrop filter when the current renderer supports shader image filters.

  • Call PixelizeOverlay.precacheShader() before first use to reduce the first activation hitch.

  • Compatibility: PixelizeOverlay uses ImageFilter.shader, which requires the Impeller rendering backend. Support is determined at runtime through ImageFilter.isShaderFilterSupported, so it depends on the active renderer rather than the operating system alone. When shader image filters are not supported, PixelizeOverlay falls back to a transparent full-size overlay: the backdrop remains unchanged and no UnsupportedError is thrown. In the same situation, PixelizeOverlay.precacheShader() completes without loading a shader program. See Flutter's Impeller documentation for current platform availability and enablement instructions.

     

• VignetteOverlay()

  • Add a soft perimeter vignette with configurable intensity, sepia tone, corner radius, and edge falloff.

  • Use radius to control the inner corner rounding and edgeFalloff to control how far the vignette extends from the screen edges.

     

• Convenient API for Overlay Management

  • Easily add, remove, and manage overlays with showFancyOverlay and removeFancyOverlay BuildContext extensions.
  • Support for multiple simultaneous overlays without conflicts.
  • Each Overlay keeps one active instance of a runtime type; showing that type again replaces only its instance in the nearest Overlay.

BuildContext extension methods

• call context.showFancyOverlay to show overlay, like this:

     context.showFancyOverlay(
       FallingWidgetsOverlay(
         config: FallingWidgetsOverlayConfig(
           children: [
             Icon(
               CupertinoIcons.snow,
               color: Colors.white,
             ),
           ],
         ),
       ),
     );

• call context.removeFancyOverlay<T>() to remove specific overlay, like this:

     context.removeFancyOverlay<FallingWidgetsOverlay>();

• call context.removeAllFancyOverlays() to remove all overlays that was shown with context.showFancyOverlay:

     context.removeAllFancyOverlays();