Function loop

examples/FireCylinder/FireCylinder.h:173–215

}

void loop() {
    // The main program loop that runs continuously
    
    // Set the overall brightness from the UI slider
    FastLED.setBrightness(brightness);
    
    // Get the selected color palette
    fl::CRGBPalette16 myPal = getPalette();
    
    // Get the current time in milliseconds
    uint32_t now = fl::millis();
    
    // Update the animation speed from the UI slider
    timeScale.setSpeed(speedY);
    
    // Calculate the current y-offset for animation (makes the fire move)
    uint32_t y_speed = timeScale.update(now);
    
    // Loop through every LED in our cylindrical matrix
    for (int width = 0; width < WIDTH; width++) {
        for (int height = 0; height < HEIGHT; height++) {
            // Calculate which color to use from our palette for this LED
            // This function handles the cylindrical mapping using sine/cosine
            uint8_t palette_index =
                getPaletteIndex(now, width, WIDTH, height, HEIGHT, y_speed);
            
            // Get the actual RGB color from the palette
            // BRIGHTNESS ensures we use the full brightness range
            fl::CRGB c = ColorFromPalette(myPal, palette_index, BRIGHTNESS);
            
            // Convert our 2D coordinates to the 1D fl::array index
            // We use (WIDTH-1)-width and (HEIGHT-1)-height to flip the coordinates
            // This makes the fire appear to rise from the bottom
            int index = xyMap((WIDTH - 1) - width, (HEIGHT - 1) - height);
            
            // Set the LED color in our fl::array
            leds[index] = c;
        }
    }
    
    // Send the color data to the actual LEDs
    FastLED.show();
}