Function wave8EncodeQuadLane

src/platforms/esp/32/drivers/spi/wave8_encoder_spi.h:127–163

@brief Encode quad-lane LED data using wave8 + 4-lane transposition For ESP32-S3 quad-SPI mode (4 parallel data lines). Each set of 4 LED bytes expands to 32 bytes (4 Wave8Byte structures transposed). @param lanes Array of 4 lane spans (must all have same size) @param output Output buffer for transposed wave8 data @param lut Wave8 expansion lookup table @return Number of bytes written to output

/// @param lut Wave8 expansion lookup table
/// @return Number of bytes written to output (lanes[0].size() * 32)
inline size_t wave8EncodeQuadLane(
    fl::span<const u8> lanes[4],
    fl::span<u8> output,
    const Wave8BitExpansionLut& lut) FL_NOEXCEPT {

    const size_t lane_size = lanes[0].size();
    for (int i = 1; i < 4; i++) {
        if (lanes[i].size() != lane_size) {
            FL_WARN("wave8EncodeQuadLane: Lane size mismatch (lane0="
                    << lane_size << " bytes, lane" << i << "=" << lanes[i].size() << " bytes)");
            return 0;
        }
    }

    const size_t required_size = lane_size * 32;
    if (output.size() < required_size) {
        FL_WARN("wave8EncodeQuadLane: Output buffer too small (need "
                << required_size << " bytes, have " << output.size() << " bytes)");
        return 0;
    }

    size_t output_idx = 0;
    for (size_t i = 0; i < lane_size; i++) {
        Wave8Byte wave8_lanes[4];
        for (int lane = 0; lane < 4; lane++) {
            detail::wave8_convert_byte_to_wave8byte(lanes[lane][i], lut, &wave8_lanes[lane]);
        }

        u8 transposed[4 * sizeof(Wave8Byte)];
        detail::wave8_transpose_4(wave8_lanes, transposed);

        fl::memcpy(output.data() + output_idx, transposed, sizeof(transposed));
        output_idx += sizeof(transposed);
    }

    return output_idx;
}

/// @brief Calculate required output buffer size for wave8 encoding
///