feat: implemented buffering with goroutines. (not fast, damn sorry)

cmd/test/trianlge.go

@@ -77,7 +77,7 @@ func (t *Tri) Update(c *Context) {
 		}
 		tt := *t
 		tt.Spawned = true
-		tt.Visible = false
+		tt.Visible = true
 		tt.Disconnect()
 		if c.Spawn(&tt) == nil {
 			counter++

engine.go

@@ -11,7 +11,7 @@ import (
 )
 
 const (
-	LayerBufSize = 0
+	LayerBufSize = 100
 )
 
 type GraphicsLibrary = ebiten.GraphicsLibrary
@@ -115,6 +115,12 @@ func NewEngine(
 	ret.handleEvents = make(EventChan)
 	ret.Objects = &Objects{}
 	ret.buttons = MouseButtonMap{}
+
+	siz := ret.RealWinSize()
+	w, h := int(siz.X), int(siz.Y)
+	for i:=0 ; i<len(ret.bufs) ; i++ {
+		ret.bufs[i] = NewImage(w, h)
+	}
 	return ret
 }
 
@@ -295,7 +301,8 @@ func (e *engine) Update() error {
 	return nil
 }
 
-func (e *engine) Draw(i *ebiten.Image) {
+func (e *engine) Draw(image *ebiten.Image) {
+	var wg sync.WaitGroup
 	e.dt = time.Since(e.lastTime).Seconds()
 	eng := (*Engine)(e)
 	m := map[Layer][]Drawer{}
@@ -317,15 +324,53 @@ func (e *engine) Draw(i *ebiten.Image) {
 
 	// Drawing layers.
 	layers := maps.NewSparse[Layer, []Drawer](nil, m)
-	c := &Context{Engine: eng, typ: drawContext, Image: i}
-	for layer := range layers.Chan() {
+	ln := layers.Size()
+	pageN := ln / LayerBufSize
+	mod := ln % LayerBufSize
+	chn := layers.Chan()
+	opts := &ebiten.DrawImageOptions{GeoM: Matrix{}}
+	for n := 0 ; n<pageN ; n++ {
+		for i:=0 ; i<LayerBufSize ; i++ {
+			layer := <-chn
+			buf := e.bufs[i]
+			c := &Context{Engine: eng, typ: drawContext, Image: buf}
+			wg.Add(1)
+			go func() {
 				for _, drawer := range layer {
 					drawer.Draw(c)
 				}
+				wg.Done()
+			}()
+		}
+		wg.Wait()
+		for _, buf := range e.bufs {
+			image.DrawImage(buf, opts)
+			buf.Clear()
+		}
 	}
 
-	// Empty the buff to generate it again.
+	for i:=0 ; i<mod ; i++ {
+		layer := <-chn
+		buf := e.bufs[i]
+		c := &Context{Engine: eng, typ: drawContext, Image: buf}
+		wg.Add(1)
+		go func() {
+			for _, drawer := range layer {
+				drawer.Draw(c)
+			}
+			wg.Done()
+		}()
+	}
+	wg.Wait()
+	for i:=0 ; i<mod ; i++ {
+		buf := e.bufs[i]
+		image.DrawImage(buf, opts)
+		buf.Clear()
+	}
+
+	// Empty the camera buffer to generate it again.
 	eng.Camera.buffered = false
+
 	e.lastTime = time.Now()
 }