func printLoop(ch <-chan []grid2d.Update, g grid2d.Grid, cns *census.DirCensus, cond *sync.Cond, numUpdates *int64, clearScreen bool) {
// Try to keep rendering smooth.
runtime.LockOSThread()
for _ = range ch {
if clearScreen {
// TODO(dnesting): use termcap/terminfo to do this more portably.
fmt.Print("[H")
}
term.PrintWorld(os.Stdout, g)
fmt.Println()
if clearScreen {
fmt.Print("[J")
}
// Write some summary stats after the rendering.
fmt.Printf("%d updates\n", atomic.LoadInt64(numUpdates))
fmt.Printf("%d/%d orgs (%d/%d species, %d recorded)\n", cns.Count(), cns.CountAllTime(), cns.Distinct(), cns.DistinctAllTime(), cns.NumRecorded())
if loc := g.Get(0, 0); loc != nil {
fmt.Printf("random: %v\n", loc.Value())
}
// If we're running with --sync, signal to any goroutines waiting on a rendering that
// it's OK for them to continue again.
if cond != nil {
cond.Broadcast()
}
}
}
func startUpdateTracker(g grid2d.Grid, numUpdates *int64) {
ch := make(chan []grid2d.Update, 0)
go func() {
for updates := range ch {
atomic.AddInt64(numUpdates, int64(len(updates)))
}
}()
g.Subscribe(ch)
}
// StartAll finds all organisms driven by Cpu instances, and spawns a goroutine
// to begin executing each Cpu instance found.
func StartAll(g grid2d.Grid) {
var locs []grid2d.Point
g.Locations(&locs)
for _, p := range locs {
if o, ok := p.V.(*org.Organism); ok {
if c, ok := o.Driver.(*Cpu); ok {
go c.Run(o)
}
}
}
}
// Count counts the number of occupants in g that satisfy fn.
func Count(g grid2d.Grid, fn CounterFunc) int {
var locs []grid2d.Point
g.Locations(&locs)
var count int
for _, p := range locs {
if fn(p.V) {
count += 1
}
}
return count
}
func startOrg(g grid2d.Grid) {
c := cpu1.Random()
o := org.Random()
o.Driver = c
o.AddEnergy(initialEnergy)
for {
// PutRandomly might fail if there's no room, so just keep trying.
if _, loc := g.PutRandomly(o, org.PutWhenFood); loc != nil {
go c.Run(o)
break
}
}
}
func startAndMaintainOrgs(g grid2d.Grid) {
// Obtain an initial count before we start anything executing.
mCount := maintain.Count(g, isOrg)
ch := make(chan []grid2d.Update, 0)
g.Subscribe(ch)
// Start all organisms currently existing in the Grid. We do this *after*
// subscribing ch so that we don't end up with a wrong count if any organisms
// divide or die.
cpu1.StartAll(g)
go maintain.Maintain(ch, isOrg, func() { startOrg(g) }, minOrgs, mCount)
}
// PrintWorld renders g to w.
func PrintWorld(w io.Writer, g grid2d.Grid) {
points := locPool.Get().([]grid2d.Point)
width, height, _ := g.Locations(&points)
sort.Sort(byCoordinate(points))
iy, ix := 0, -1
addHeader(w, width)
for _, p := range points {
fillBefore(w, p.X, p.Y, width, &ix, &iy)
writeRune(w, RuneForOccupant(p.V))
ix += 1
}
locPool.Put(points)
fillBefore(w, width, height-1, width, &ix, &iy)
writeRune(w, rightRune)
writeRune(w, '\n')
addFooter(w, width)
}
func startPrintLoop(g grid2d.Grid, cns *census.DirCensus, cond *sync.Cond, numUpdates *int64, clearScreen bool) {
// We want to use chanbuf.Tick to ensure renders occur at specific intervals regardless
// of the rate at which updates arrive. To prevent the notification channel from backing up
// and causing deadlock, we buffer using a chanbuf.Trigger (since we don't care about the
// update messages themselves). We could have used a time.Tick instead, but we'd need to
// do something special to ensure this loop exits when the notifications stop.
// grid notifier -> updateCh -> trigger -> tick -> print world
// grid notifier first dispatches an update the moment it occurs
// trigger consumes the event and flags that an update occurred
// tick fires every freq, halting when trigger reports it's closed
// printLoop renders the grid every time tick fires
updateCh := make(chan []grid2d.Update, 0)
trigger := chanbuf.Trigger()
freq := time.Duration(1000000.0/printRate) * time.Microsecond
go chanbuf.Feed(trigger, grid2d.NotifyToInterface(updateCh))
tickCh := chanbuf.Tick(trigger, freq, true)
g.Subscribe(updateCh)
go printLoop(grid2d.NotifyFromInterface(tickCh), g, cns, cond, numUpdates, clearScreen)
}
func startCensus(g grid2d.Grid) *census.DirCensus {
// Create a new Census that writes to /tmp/census when a population grows to 40.
cns, err := census.NewDirCensus("/tmp/census", func(p census.Population) bool { return p.Count > 40 })
if err != nil {
fmt.Printf("Error creating census: %v\n", err)
os.Exit(1)
}
// Use human times.
timeNow := func(interface{}) interface{} { return time.Now() }
ch := make(chan []grid2d.Update, 0)
g.Subscribe(ch)
// Populate the Census with what's already in the world (perhaps restored from an autosave).
// Assumes nothing in the world is changing yet.
grid2d.ScanForCensus(cns, g, timeNow, orgHash)
// Start monitoring for changes
go grid2d.WatchForCensus(cns, ch, timeNow, orgHash)
return cns
}