player and dimension loader with ecs system

server/ecs/dispatcher.go

@@ -0,0 +1,44 @@
+package ecs
+
+import "sync"
+
+type Dispatcher struct {
+	waiters map[string][]*sync.WaitGroup
+	tasks   []func(w *World, wg *sync.WaitGroup)
+}
+
+func NewDispatcher() *Dispatcher {
+	return &Dispatcher{
+		waiters: make(map[string][]*sync.WaitGroup),
+		tasks:   nil,
+	}
+}
+
+func (d *Dispatcher) Add(s System, name string, deps []string) {
+	var start sync.WaitGroup
+	start.Add(len(deps))
+	for _, dep := range deps {
+		if wg, ok := d.waiters[dep]; ok {
+			d.waiters[dep] = append(wg, &start)
+		} else {
+			panic("Unknown deps: " + dep)
+		}
+	}
+	d.tasks = append(d.tasks, func(w *World, done *sync.WaitGroup) {
+		start.Wait()
+		defer done.Done()
+		s.Update(w)
+		for _, wg := range d.waiters[name] {
+			wg.Done()
+		}
+	})
+}
+
+func (d *Dispatcher) Run(w *World) {
+	var wg sync.WaitGroup
+	wg.Add(len(d.tasks))
+	for _, f := range d.tasks {
+		go f(w, &wg)
+	}
+	wg.Wait()
+}