Crate ferriswheel 

RGB LED ring effects and animations.

This crate provides reusable animation effects for circular LED rings. It is no_std compatible for embedded use.

All effects implement the Effect trait, which provides a uniform interface for rendering animations into an RGB8 buffer.

Available Effects

• RainbowEffect — smooth rainbow gradient rotation
• PulseEffect — heartbeat animation: sine-wave brightness with a pause at the floor
• BreatheEffect — breathing animation: symmetric full-sine brightness with no pause
• SpinnerEffect — rotating dot with fading tail (linear decay, brightness floor)
• MeteorEffect — meteor / comet: bright head with exponentially-decaying tail
• TwinkleEffect — ambient sparkle: random LEDs flash to peak brightness then decay
• FireEffect — fire simulation: heat diffuses upward from a sparking base
• CylonEffect — Cylon / bouncing scanner: bright head sweeps back and forth with fading tail
• KnightRiderEffect — Knight Rider / dual-headed scanner: two heads sweep in opposite directions
• ChaseEffect — moving a solid segment around the ring
• FlashEffect — rapid on/off toggle with configurable duty cycle
• ProgressEffect — proportional ring fill
• SectionEffect — weighted color sections on a ring
• RainbowCometEffect — Rainbow comet: orbiting head with a hue-cycling fading tail

Utilities

• ColorPalette — three-color theme for effects
• fill_solid — fill a buffer with a single color
• sine_wave — half-wave rectified sine lookup (0→255→0 then plateau at 0)
• sine_full — full symmetric sine lookup (0→255→0, no plateau)
• scale_brightness — scale an RGB color’s brightness
• lerp_color — linearly interpolate between two colors

Color type

All effects operate on RGB8, re-exported here from the rgb crate. Downstream crates do not need a direct rgb dependency — use ferriswheel::RGB8 is sufficient.

Example

use ferriswheel::{Effect, RainbowEffect, Direction, RGB8};

let mut rainbow = RainbowEffect::new(12).unwrap();
let mut buffer = [RGB8::default(); 12];

// Fill the buffer with rainbow colors and advance animation
rainbow.update(&mut buffer).unwrap();

// Use as a trait object
let effect: &dyn Effect = &rainbow;
effect.current(&mut buffer).unwrap();

Structs

BreatheEffect

A smooth breathing animation effect.

ChaseEffect

A chase effect where a solid segment moves around the ring.

ColorPalette

A three-color theme palette.

CylonEffect

A Cylon / bouncing scanner effect.

FireEffect

A fire / flame animation effect.

FlashEffect

A flash effect that toggles all LEDs between two colors.

KnightRiderEffect

A Knight Rider / dual-headed scanner effect.

MeteorEffect

A meteor / comet effect with an exponentially-decaying tail.

ProgressEffect

A progress indicator effect that fills the ring proportionally.

PulseEffect

A breathing/pulsing animation effect.

RainbowCometEffect

A rainbow comet effect with a hue-cycling fading tail.

RainbowEffect

A rainbow animation effect for LED rings.

SectionEffect

An effect that divides the ring into weighted color sections.

SpinnerEffect

A rotating spinner effect with a fading tail.

TwinkleEffect

An ambient twinkle / sparkle effect.

Enums

Direction

Direction of animation rotation.

EffectError

Error type for effect configuration and operations.

Constants

MAX_LEDS

Maximum supported number of LEDs in a ring.

MAX_SECTIONS

Maximum number of sections supported by SectionEffect.

Traits

Effect

A reusable LED ring effect.

Functions

fill_solid

Fills all elements of buffer with the given color.

hsv_to_rgb

Converts HSV color values to RGB.

lerp_color

Linearly interpolates between two colors.

scale_brightness

Scales a single color channel by a brightness factor (0–255).

sine_full

Returns a full symmetric sine-wave value for the given phase.

sine_wave

Returns a sine-wave value for the given phase.

Type Aliases

RGB8

8-bit RGB