Function writeUCS7604

src/fl/channels/channel.cpp.hpp:320–376

@brief Encode UCS7604 pixel data into the channel data buffer @param data Output byte vector (cleared by caller) @param pixelIterator Pixel iterator with color order and RGBW conversion @param encoder ClocklessEncoder value identifying the UCS7604 mode @param settings Channel settings (for gamma override) @param rgbOrder RGB ordering for current control reordering

/// @param settings Channel settings (for gamma override)
/// @param rgbOrder RGB ordering for current control reordering
void writeUCS7604(fl::vector_psram<u8>* data, PixelIterator& pixelIterator,
                  ClocklessEncoder encoder, const ChannelOptions& settings,
                  EOrder rgbOrder) {
    // Map encoder enum to UCS7604Mode
    UCS7604Mode mode;
    switch (encoder) {
        case ClocklessEncoder::CLOCKLESS_ENCODER_UCS7604_8BIT:
            mode = UCS7604Mode::UCS7604_MODE_8BIT_800KHZ;
            break;
        case ClocklessEncoder::CLOCKLESS_ENCODER_UCS7604_16BIT:
            mode = UCS7604Mode::UCS7604_MODE_16BIT_800KHZ;
            break;
        case ClocklessEncoder::CLOCKLESS_ENCODER_UCS7604_16BIT_1600:
            mode = UCS7604Mode::UCS7604_MODE_16BIT_1600KHZ;
            break;
        default:
            // Should never happen — caller already checked
            mode = UCS7604Mode::UCS7604_MODE_16BIT_800KHZ;
            break;
    }

    // Get current control from global UCS7604 brightness
    UCS7604CurrentControl current = ucs7604::brightness();

    // Reorder current control values to match wire order (same logic as UCS7604ControllerT)
    u8 rgb_currents[3] = {current.r, current.g, current.b};
    u8 pos0 = (static_cast<int>(rgbOrder) >> 6) & 0x3;
    u8 pos1 = (static_cast<int>(rgbOrder) >> 3) & 0x3;
    u8 pos2 = (static_cast<int>(rgbOrder) >> 0) & 0x3;
    UCS7604CurrentControl wire_current(
        rgb_currents[pos0], rgb_currents[pos1], rgb_currents[pos2], current.w);

    // Get gamma LUT
    float gamma = settings.mGamma.value_or(2.8f);
    fl::shared_ptr<const Gamma8> gamma8 = Gamma8::getOrCreate(gamma);

    bool is_rgbw = pixelIterator.get_rgbw().active();
    size_t num_leds = pixelIterator.size();

    // (#2558) UCS7604 is a 4-channel chipset (always RGBW). If the user
    // configured this channel for 5-channel RGBWW (warm-W + cool-W), the
    // chipset can't carry the second W byte. Warn loudly — silently dropping
    // the white channels would be very hard to diagnose. The pixel iterator
    // continues to emit RGB-only bytes (is_rgbw=false) so the strip still
    // lights up, just without the W diode.
    if (pixelIterator.get_rgbww().active() && !is_rgbw) {
        FL_WARN_ONCE("UCS7604 cannot carry 5-channel RGBWW — this chipset "
                     "always emits 4-channel RGBW. The warm/cool white "
                     "channels in your Rgbww config will be dropped. "
                     "Set ChannelOptions.mWhiteCfg = Rgbw{...} instead to "
                     "silence this warning.");
    }

    // Encode into the data buffer
    encodeUCS7604(pixelIterator, num_leds, fl::back_inserter(*data),
                  mode, wire_current, is_rgbw, gamma8.get());
}