Remove memory leak (#61)

* Integrate Go profiler

* Exclude profile logs

* Remove memory leak

* Remove obsolete API call

Author: magicoder10

.dockerignore

@@ -2,3 +2,4 @@
 *.md
 /build
 *.md
+/perf

.gitignore

@@ -3,3 +3,6 @@
 
 # Build
 /build
+
+# Performance diagnostic files
+/perf

game/gamemap/map.go

@@ -54,7 +54,6 @@ type Map struct {
 
 func (m Map) DrawMap() {
 	m.batch.DrawSprite(m.screenX, m.screenY, math.MaxInt32, mapBound, 1)
-	m.batch.RenderBatch()
 }
 
 func (m Map) DrawGrid(batch graphics.Batch) {

graphics/ebiten.go

@@ -19,16 +19,16 @@ type Ebiten struct {
 	reverseY bool
 	texts    []*ebitenText
 	batches  []*ebitenBatch
+	buffer *ebiten.Image
 }
 
-func (e Ebiten) Clear() {
-	e.texts = make([]*ebitenText, 0)
-	e.batches = make([]*ebitenBatch, 0)
+func (e *Ebiten) initBuffer(width int, height int) {
+	e.buffer = ebiten.NewImage(width, height)
 }
 
-func (e *Ebiten) NewText(face font.Face, x int, y int, width int, height int, scale float64, alignment alignment) Text {
+func (e *Ebiten) NewText(face font.Face, x int, y int, width int, height int, _ float64, alignment alignment) Text {
 	buf := bytes.Buffer{}
-	return &ebitenText{
+	txt := &ebitenText{
 		x:         x,
 		y:         y,
 		width:     width,
@@ -38,9 +38,11 @@ func (e *Ebiten) NewText(face font.Face, x int, y int, width int, height int, sc
 		graphics:  e,
 		alignment: alignment,
 	}
+	e.texts = append(e.texts, txt)
+	return txt
 }
 
-func (e *Ebiten) RenderTexts(screen *ebiten.Image) {
+func (e *Ebiten) RenderTexts(target *ebiten.Image) {
 	for _, t := range e.texts {
 		bound := text.BoundString(t.fontFace, t.textContent)
 		width := float64(bound.Max.X - bound.Min.X)
@@ -49,17 +51,19 @@ func (e *Ebiten) RenderTexts(screen *ebiten.Image) {
 		x := float64(t.x) + float64(t.width)/2 - width/2
 		y := float64(t.y) + float64(t.height)/2 - height/2
 
-		adjustedY := adjustY(e.reverseY, screen, int(y), 0)
+		adjustedY := adjustY(e.reverseY, target, int(y), 0)
 
 		switch t.alignment {
 		case AlignCenter:
-			text.Draw(screen, t.textContent, t.fontFace, int(x), adjustedY, color.White)
+			text.Draw(target, t.textContent, t.fontFace, int(x), adjustedY, color.White)
 		}
 	}
 }
 
 func (e *Ebiten) StartNewBatch(spriteSheet image.Image) Batch {
-	return newEbitenBatch(ebiten.NewImageFromImage(spriteSheet), e)
+	batch := newEbitenBatch(ebiten.NewImageFromImage(spriteSheet), e)
+	e.batches = append(e.batches, batch)
+	return batch
 }
 
 func (e Ebiten) SetCursorVisible(isVisible bool) {
@@ -72,9 +76,10 @@ func (e Ebiten) SetCursorVisible(isVisible bool) {
 
 func (e *Ebiten) Render(screen *ebiten.Image) {
 	for _, batch := range e.batches {
-		batch.renderBatch(screen)
+		batch.renderBatch(e.buffer)
 	}
-	e.RenderTexts(screen)
+	e.RenderTexts(e.buffer)
+	screen.DrawImage(e.buffer, nil)
 }
 
 func NewEbiten(reverseY bool) Ebiten {
@@ -102,11 +107,9 @@ func (t *ebitenText) Write(p []byte) (int, error) {
 }
 
 func (t *ebitenText) Draw() {
-	t.buf.Flush()
+	_ = t.buf.Flush()
 	buf, _ := ioutil.ReadAll(t.buf)
 	t.textContent = string(buf)
-
-	t.graphics.texts = append(t.graphics.texts, t)
 }
 
 var _ Batch = (*ebitenBatch)(nil)
@@ -117,11 +120,7 @@ type ebitenBatch struct {
 	spritesDrawn []*spriteDrawn
 }
 
-func (e *ebitenBatch) RenderBatch() {
-	e.ebiten.batches = append(e.ebiten.batches, e)
-}
-
-func (e *ebitenBatch) renderBatch(screen *ebiten.Image) {
+func (e *ebitenBatch) renderBatch(target *ebiten.Image) {
 	sort.SliceStable(e.spritesDrawn, func(i, j int) bool {
 		if e.ebiten.reverseY {
 			return e.spritesDrawn[i].z > e.spritesDrawn[j].z
@@ -151,13 +150,13 @@ func (e *ebitenBatch) renderBatch(screen *ebiten.Image) {
 		op.GeoM.Scale(spriteDrawn.scale, spriteDrawn.scale)
 
 		scaledHeight := float64(spriteDrawn.imageBound.Height) * spriteDrawn.scale
-		adjustedY := adjustY(e.ebiten.reverseY, screen, spriteDrawn.y, scaledHeight)
+		adjustedY := adjustY(e.ebiten.reverseY, target, spriteDrawn.y, scaledHeight)
 		op.GeoM.Translate(
 			float64(spriteDrawn.x),
 			float64(adjustedY),
 		)
 
-		screen.DrawImage(e.spriteSheet.SubImage(bound).(*ebiten.Image), op)
+		target.DrawImage(e.spriteSheet.SubImage(bound).(*ebiten.Image), op)
 	}
 	e.spritesDrawn = make([]*spriteDrawn, 0)
 }

graphics/graphics.go

@@ -27,11 +27,9 @@ type Text interface {
 
 type Batch interface {
 	DrawSprite(x int, y int, z int, imageBound Bound, scale float64)
-	RenderBatch()
 }
 
 type Graphics interface {
-	Clear()
 	NewText(face font.Face, x int, y int, width int, height int, scale float64, alignment alignment) Text
 	StartNewBatch(spriteSheet image.Image) Batch
 	SetCursorVisible(isVisible bool)

graphics/window.go

@@ -29,6 +29,7 @@ type EbitenWindow struct {
 func (e *EbitenWindow) Init() {
 	ebiten.SetWindowSize(e.windowConfig.Width, e.windowConfig.Height)
 	ebiten.SetWindowTitle(e.windowConfig.Title)
+	e.ebiten.initBuffer(e.windowConfig.Width, e.windowConfig.Height)
 	e.prevTime = time.Now()
 }
 

main.go

@@ -1,7 +1,10 @@
 package main
 
 import (
+	"flag"
 	"log"
+	"os"
+	"runtime/pprof"
 
 	"candy/assets"
 	"candy/graphics"
@@ -11,7 +14,33 @@ import (
 	"github.com/hajimehoshi/ebiten/v2"
 )
 
+var cpuprofile = flag.String("cpuprofile", "", "write cpu profile to file")
+var memprofile = flag.String("memprofile", "", "write memory profile to this file")
+
 func main() {
+	flag.Parse()
+	// Enable CPU profiling
+	if *cpuprofile != "" {
+		f, err := os.Create(*cpuprofile)
+		if err != nil {
+			log.Fatal(err)
+		}
+		defer f.Close()
+		pprof.StartCPUProfile(f)
+		defer pprof.StopCPUProfile()
+	}
+
+	// Enable memory profiling
+	if *memprofile != "" {
+		f, err := os.Create(*memprofile)
+		if err != nil {
+			log.Fatal(err)
+		}
+		defer f.Close()
+		pprof.WriteHeapProfile(f)
+		return
+	}
+
 	eb := graphics.NewEbiten(true)
 
 	ass, err := assets.LoadAssets("public")

screen/game.go

@@ -44,8 +44,6 @@ func (g Game) Draw() {
 
 	g.backpack.Draw(g.spriteSheetBatch)
 	g.rightSideBar.Draw(g.spriteSheetBatch)
-
-	g.spriteSheetBatch.RenderBatch()
 }
 
 func (g Game) HandleInput(in input.Input) {

screen/signin.go

@@ -39,7 +39,6 @@ func (s SignIn) Destroy() {
 
 func (s SignIn) Draw() {
 	s.batch.DrawSprite(0, 0, 1, signInBackgroundBound, 1)
-	s.batch.RenderBatch()
 }
 
 func (s SignIn) Update(timeElapsed time.Duration) {

scripts/perf-cpu

@@ -0,0 +1,7 @@
+#!/bin/bash
+
+rm -rf perf
+mkdir perf
+
+go build -o build/main main.go
+./build/main --cpuprofile=perf/cpu.perf

scripts/perf-mem

@@ -0,0 +1,7 @@
+#!/bin/bash
+
+rm -rf perf
+mkdir perf
+
+go build -o build/main main.go
+./build/main --memprofile=perf/memory.perf

ui/engine.go

@@ -47,7 +47,6 @@ func (r RenderEngine) Draw() {
 		Height: imageBound.Max.Y,
 	}
 	r.batch.DrawSprite(0, 0, 0, bound, 1)
-	r.batch.RenderBatch()
 }
 
 func (r RenderEngine) generateLayout(component Component) {