// do_blink listens on the provided channel for specified color and blinks it at an
// interval.
func do_blink(color <-chan byte) {
var c byte
var intensity byte
tick := time.NewTicker(BLINK_INTERVAL)
LOOP:
for {
select {
case c_new, ok := <-color:
if !ok {
break LOOP
}
piglow.Ring(c, 0)
c = c_new
case <-tick.C:
if intensity == 0 {
intensity = INTENSITY_MAX
} else {
intensity = 0
}
piglow.Ring(c, intensity)
}
}
err := piglow.ShutDown()
if err != nil {
log.Printf("failed to shutdown piglow: %v", err)
}
}
// displayUtilization takes a utilization percentage (between 0 and 1.0) and a
// brightness percentage (between 0 and 1.0) and displays them via the PiGlow's
// rings. 0% utilization -> no LEDs lit up. 50% utilization -> half the LEDs lit
// up, starting in the center. 100% utilization -> all LEDs lit up.
func displayUtilization(utilization float64, brightness float64) {
brightnessByte := byte(math.Floor(brightness*255.0 + 0.5))
// Using 6 here instead of 5 so no LEDs are lit for no utilization.
lastRing := 6 - int(math.Floor(utilization*6.0+0.5))
for ring := 0; ring <= 5; ring++ {
if ring >= lastRing {
piglow.Ring(byte(ring), brightnessByte)
} else {
piglow.Ring(byte(ring), 0x00)
}
}
}