FixedPointEffect

Source: FixedPointEffect.h

FixedPointEffect

class FixedPointEffect

src/light/effects/FixedPointEffect.h:22

Inherits: EffectBase

Effect: sub-pixel shapes, drawn between pixels so small panels move smoothly.

Author: concept and the original fixed-point canvas demos by Sutaburosu, in FastLED, via MoonLight.

Public Attributes

uint8_t demo = kAll : Which demonstration is showing.

uint8_t bpm = 20 : How fast the whole scene runs, in BPM like every other effect here.

uint8_t fade = 70 : How much of the previous frame survives, which is what leaves the trail.

uint8_t dwell = 12 : Seconds each demo holds before all moves to the next.

uint8_t drift = 2 : How far the scene drifts from the panel's center, in pixels; 0 pins it.

uint8_t zoom = 150 : The camera, which pushes in and settles back on a cycle; 0 holds it still.

Public Methods

virtual inline const char * tags() const override : The catalog tags shown on this effect's card.

virtual inline Dim dimensions() const override : This effect draws in two dimensions.

virtual inline void defineControls() override : Bind the demo selector, the rate, the trail, the dwell, the drift and the camera.

virtual inline void prepare() override : Clear the shared trail, so a demo change never joins two unrelated figures.

virtual inline void tick() override : The hot tick, which by default ticks every enabled child and times each.

Public Static Attributes

constexpr const char * kDemoNames = { "all", "clock", "orbits", "star web", "spirograph", "lissajous", "cube thin", "cube thick", "walkers", "boids", "hypotrochoid", "tree"}

constexpr uint8_t kCycled = kDemoCount - 1 : How many demos all rotates through.

Public Types

enum : Which demonstration, or all to cycle them.

Value	Description
kAll
kClock
kOrbits
kStarWeb
kSpirograph
kLissajous
kCubeThin
kCubeThick
kWalkers
kBoids
kHypotrochoid
kTree
kDemoCount

More info

The point is the technique, not the picture

On a 16x16 panel a clock hand drawn on whole pixels jumps a full pixel at a time and reads as broken. The same hand placed at a fractional position and antialiased moves smoothly, because a pixel's brightness carries the fraction its position cannot. Everything here is built from that one idea, so a small matrix gets motion a whole-pixel renderer cannot express at any frame rate.

The shapes come from the sub-pixel family in draw.h, disc, ring, strokeLine and line, which work in the 24.8 pos_t the whole draw layer speaks. Nothing here computes coverage itself.