code: func (d *DisplayBuffer) SetPixel(x, y, c int) {
  	idx := x + (y/d.pageSize)*d.width
  	bit := uint(y) % uint(d.pageSize)
  	if c == 0 {
  		d.buffer[idx] &= ^(1 << bit)
  	} else {
  		d.buffer[idx] |= (1 << bit)
  	}
  }
docs: // SetPixel sets the x, y pixel with c color