in neopixel.ts [403:412]
private setBufferRGB(offset: number, red: number, green: number, blue: number): void {
if (this._mode === NeoPixelMode.RGB_RGB) {
this.buf[offset + 0] = red;
this.buf[offset + 1] = green;
} else {
this.buf[offset + 0] = green;
this.buf[offset + 1] = red;
}
this.buf[offset + 2] = blue;
}