Add global function to create textures / render targets

example/blocks/game.go

@@ -3,6 +3,7 @@ package blocks
 import (
 	"github.com/hajimehoshi/ebiten/graphics"
 	_ "image/png"
+	"sync"
 )
 
 type Size struct {
@@ -32,20 +33,11 @@ func NewGame() *Game {
 	game := &Game{
 		sceneManager: NewSceneManager(NewTitleScene()),
 		input:        NewInput(),
+		textures:     NewTextures(),
 	}
 	return game
 }
 
-func (game *Game) SetTextureFactory(textureFactory graphics.TextureFactory) {
-	game.textures = NewTextures(textureFactory)
-	for name, path := range texturePaths {
-		game.textures.RequestTexture(name, path)
-	}
-	for name, size := range renderTargetSizes {
-		game.textures.RequestRenderTarget(name, size)
-	}
-}
-
 func (game *Game) isInitialized() bool {
 	for name := range texturePaths {
 		if !game.textures.Has(name) {
@@ -60,7 +52,17 @@ func (game *Game) isInitialized() bool {
 	return true
 }
 
+var once sync.Once
+
 func (game *Game) Update() {
+	once.Do(func() {
+		for name, path := range texturePaths {
+			game.textures.RequestTexture(name, path)
+		}
+		for name, size := range renderTargetSizes {
+			game.textures.RequestRenderTarget(name, size)
+		}
+	})
 	if !game.isInitialized() {
 		return
 	}

example/blocks/textures.go

@@ -18,7 +18,6 @@ type nameSize struct {
 }
 
 type Textures struct {
-	textureFactory    graphics.TextureFactory
 	texturePaths      chan namePath
 	renderTargetSizes chan nameSize
 	textures          map[string]graphics.TextureId
@@ -26,9 +25,8 @@ type Textures struct {
 	sync.RWMutex
 }
 
-func NewTextures(textureFactory graphics.TextureFactory) *Textures {
+func NewTextures() *Textures {
 	textures := &Textures{
-		textureFactory:    textureFactory,
 		texturePaths:      make(chan namePath),
 		renderTargetSizes: make(chan nameSize),
 		textures:          map[string]graphics.TextureId{},
@@ -66,7 +64,7 @@ func (t *Textures) loopMain() {
 			if err != nil {
 				panic(err)
 			}
-			id, err := t.textureFactory.CreateTexture(img, graphics.FilterNearest)
+			id, err := graphics.CreateTexture(img, graphics.FilterNearest)
 			if err != nil {
 				panic(err)
 			}
@@ -78,7 +76,7 @@ func (t *Textures) loopMain() {
 		name := s.name
 		size := s.size
 		go func() {
-			id, err := t.textureFactory.CreateRenderTarget(size.Width, size.Height, graphics.FilterNearest)
+			id, err := graphics.CreateRenderTarget(size.Width, size.Height, graphics.FilterNearest)
 			if err != nil {
 				panic(err)
 			}

graphics/texturefactory.go

@@ -17,7 +17,27 @@ type TextureId int
 // all alpha of a render target is maximum.
 type RenderTargetId int
 
+var currentTextureFactory TextureFactory
+
 type TextureFactory interface {
 	CreateRenderTarget(width, height int, filter Filter) (RenderTargetId, error)
 	CreateTexture(img image.Image, filter Filter) (TextureId, error)
 }
+
+func SetTextureFactory(textureFactory TextureFactory) {
+	currentTextureFactory = textureFactory
+}
+
+func CreateRenderTarget(width, height int, filter Filter) (RenderTargetId, error) {
+	if currentTextureFactory == nil {
+		panic("graphics.CreateRenderTarget: currentTextureFactory is not set.")
+	}
+	return currentTextureFactory.CreateRenderTarget(width, height, filter)
+}
+
+func CreateTexture(img image.Image, filter Filter) (TextureId, error) {
+	if currentTextureFactory == nil {
+		panic("graphics.CreateTexture: currentTextureFactory is not set")
+	}
+	return currentTextureFactory.CreateTexture(img, filter)
+}

ui/run.go

@@ -11,12 +11,10 @@ import (
 type Game interface {
 	Draw(context graphics.Context)
 	Update()
-	SetTextureFactory(textureFactory graphics.TextureFactory)
 }
 
 func Run(u UI, game Game, width, height, scale int, title string, fps int) {
 	canvas := u.Start(width, height, scale, title)
-	game.SetTextureFactory(canvas)
 
 	frameTime := time.Duration(int64(time.Second) / int64(fps))
 	tick := time.Tick(frameTime)

ui/ui.go

@@ -11,7 +11,6 @@ type UI interface {
 }
 
 type Canvas interface {
-	graphics.TextureFactory
 	Draw(func(graphics.Context))
 	IsClosed() bool
 }