AnimartrixRing.ino

This is the minimal demo of the technique: render Animartrix into a rectangular grid, then sample a circle out of that grid with a ScreenMap and Fx2dTo1d.

This is the minimal demo of the technique: render Animartrix into a rectangular grid, then sample a circle out of that grid with a ScreenMap and Fx2dTo1d. Nothing else. No audio, no state machine, no orchestration.

Animartrix (16x16 grid) -> ScreenMap (circle of NUM_LEDS points) -> Fx2dTo1d (bilinear sample) -> 1D ring

Pick an animation from the dropdown, scrub the speed slider, watch how each Animartrix pattern reads once it has been wrapped around a ring. That is the whole point of this sketch.

Looking for the audio-reactive version? That moved to examples/MoodRing/, which is the product-track sketch (sound classification, per-state visual banks, mood mapping). See issue #2256.

This sketch is fully compatible with the FastLED web compiler:

1. pip install fastled
2. cd into this directory
3. run fastled

// @filter: (memory is large)

 
// Use SPI-based WS2812 driver instead of RMT on ESP32
#define FASTLED_ESP32_USE_CLOCKLESS_SPI
 
// FastLED.h must be included first to trigger precompiled headers for FastLED's
// build system
#include "FastLED.h"
 
#include "fl/fx/2d/animartrix.hpp"
#include "fl/fx/fx2d_to_1d.h"
#include "fl/fx/fx_engine.h"
#include "fl/ui/ui.h"
 
#include "auto_brightness.h"
#include "ring_screenmap.h"
 
FASTLED_TITLE("AnimartrixRing");
 
#define NUM_LEDS 244
 
#ifndef PIN_DATA
#define PIN_DATA 3 // ESP32C6 has this random pin available on the break out.
#endif             // PIN_DATA
 
#define BRIGHTNESS 8
 
// Grid dimensions for Animartrix sampling
#define GRID_WIDTH 16
#define GRID_HEIGHT 16
 
// 0.15 cm or 1.5mm -- appropriate for a dense LED rope.
#define LED_DIAMETER 0.15f
 
#define FIRST_ANIMATION fl::AnimartrixAnim::SLOW_FADE
 
CRGB leds[NUM_LEDS];
 
// Animartrix 2D effect: the source image the ring samples from.
XYMap xymap = XYMap::constructRectangularGrid(GRID_WIDTH, GRID_HEIGHT);
auto animartrix = fl::make_shared<fl::Animartrix>(xymap, FIRST_ANIMATION);
 
// ScreenMap for the ring: places each LED on a circle inside the grid.
fl::ScreenMap screenmap =
    makeRingScreenMap(NUM_LEDS, GRID_WIDTH, GRID_HEIGHT, LED_DIAMETER);
 
// The 2D-to-1D sampling effect: bilinear-samples the grid at each ring point.
auto fx2dTo1d = fl::make_shared<fl::Fx2dTo1d>(NUM_LEDS, animartrix, screenmap,
                                              fl::Fx2dTo1d::BILINEAR);
 
// FxEngine for the 1D strip
fl::FxEngine fxEngine(NUM_LEDS);
 
// UI controls. The dropdown order matches fl::AnimartrixAnim exactly, so the
// selected index can be handed straight to Animartrix::fxSet().
// Title comes from FASTLED_TITLE above -- do not declare a second fl::UITitle.
fl::UIDescription description(
    "Samples a circular ring out of a 2D Animartrix grid. @author of fx is "
    "StefanPetrick");
 
fl::UIDropdown fxIndex("Animartrix - index", {
    "RGB_BLOBS5", "RGB_BLOBS4", "RGB_BLOBS3", "RGB_BLOBS2", "RGB_BLOBS",
    "POLAR_WAVES", "SLOW_FADE", "ZOOM2", "ZOOM", "HOT_BLOB",
    "SPIRALUS2", "SPIRALUS", "YVES", "SCALEDEMO1", "LAVA1",
    "CALEIDO3", "CALEIDO2", "CALEIDO1", "DISTANCE_EXPERIMENT", "CENTER_FIELD",
    "WAVES", "CHASING_SPIRALS", "ROTATING_BLOB", "RINGS", "COMPLEX_KALEIDO",
    "COMPLEX_KALEIDO_2", "COMPLEX_KALEIDO_3", "COMPLEX_KALEIDO_4", "COMPLEX_KALEIDO_5", "COMPLEX_KALEIDO_6",
    "WATER", "PARAMETRIC_WATER", "MODULE_EXPERIMENT1", "MODULE_EXPERIMENT2", "MODULE_EXPERIMENT3",
    "MODULE_EXPERIMENT4", "MODULE_EXPERIMENT5", "MODULE_EXPERIMENT6", "MODULE_EXPERIMENT7", "MODULE_EXPERIMENT8",
    "MODULE_EXPERIMENT9", "MODULE_EXPERIMENT10", "MODULE_EXPERIMENT_SM1", "MODULE_EXPERIMENT_SM2", "MODULE_EXPERIMENT_SM3",
    "MODULE_EXPERIMENT_SM4", "MODULE_EXPERIMENT_SM5", "MODULE_EXPERIMENT_SM6", "MODULE_EXPERIMENT_SM8", "MODULE_EXPERIMENT_SM9",
    "MODULE_EXPERIMENT_SM10", "FLUFFY_BLOBS"
});
fl::UISlider timeSpeed("Time Speed", 1, -10, 10, .1);
fl::UISlider brightness("Brightness", BRIGHTNESS, 0, 255, 1);
fl::UICheckbox autoBrightness("Auto Brightness", true);
fl::UISlider autoBrightnessMax("Auto Brightness Max", 84, 0, 255, 1);
fl::UISlider autoBrightnessLowThreshold("Auto Brightness Low Threshold", 8, 0,
                                        100, 1);
fl::UISlider autoBrightnessHighThreshold("Auto Brightness High Threshold", 22,
                                         0, 100, 1);
 
void setup() {
    Serial.begin(115200);
 
    // Setup LED strip
    FastLED.addLeds<WS2812, PIN_DATA>(leds, NUM_LEDS)
        .setCorrection(TypicalLEDStrip)
        .setScreenMap(screenmap);
    FastLED.setBrightness(brightness.value());
 
    // Add the 2D-to-1D effect to FxEngine
    fxEngine.addFx(fx2dTo1d);
 
    // Dropdown index maps 1:1 onto fl::AnimartrixAnim, so point it at the boot
    // animation -- otherwise the UI would read "RGB_BLOBS5" (index 0) while
    // FIRST_ANIMATION was actually rendering. loop() reconciles from there.
    fxIndex.setSelectedIndex(static_cast<int>(FIRST_ANIMATION));
 
    Serial.println("AnimartrixRing setup complete");
}
 
void loop() {
    // Poll rather than use onChanged(): a value the web UI restores (persisted
    // or from the URL) can land before the first frame, where the change
    // detector absorbs it into its baseline and never fires. Comparing against
    // the animation we last pushed cannot miss it. Same pattern as
    // examples/Animartrix/Animartrix.ino.
    static int sLastFxIndex = -1;
    if (fxIndex.as_int() != sLastFxIndex) {
        sLastFxIndex = fxIndex.as_int();
        animartrix->fxSet(sLastFxIndex);
    }
 
    fxEngine.setSpeed(timeSpeed.value());
 
    // Draw the effect
    fxEngine.draw(millis(), leds);
 
    // Calculate final brightness
    uint8_t finalBrightness;
    if (autoBrightness.value()) {
        float avgBri = getAverageBrightness(leds);
        finalBrightness = applyBrightnessCompression(
            avgBri, static_cast<uint8_t>(autoBrightnessMax.value()),
            autoBrightnessLowThreshold.value(),
            autoBrightnessHighThreshold.value());
    } else {
        finalBrightness = static_cast<uint8_t>(brightness.value());
    }
 
    FastLED.setBrightness(finalBrightness);
    FastLED.show();
}