Remove some methods; Add Game.Initialize

example/blocks/game.go

@@ -18,7 +18,6 @@ package blocks
 
 import (
 	"github.com/hajimehoshi/ebiten"
-	"sync"
 )
 
 type Size struct {
@@ -39,21 +38,24 @@ type GameState struct {
 }
 
 type Game struct {
+	gameContext  ebiten.GameContext
 	sceneManager *SceneManager
-	ebiten       *Input
+	input        *Input
 	textures     *Textures
 }
 
 func NewGame() *Game {
 	game := &Game{
 		sceneManager: NewSceneManager(NewTitleScene()),
-		ebiten:       NewInput(),
+		input:        NewInput(),
-		textures:     NewTextures(),
 	}
 	return game
 }
 
 func (game *Game) isInitialized() bool {
+	if game.textures == nil {
+		return false
+	}
 	for name := range texturePaths {
 		if !game.textures.Has(name) {
 			return false
@@ -67,32 +69,33 @@ func (game *Game) isInitialized() bool {
 	return true
 }
 
-var once sync.Once
+func (game *Game) Initialize(g ebiten.GameContext) {
+	game.gameContext = g
+	game.textures = NewTextures(g)
+	for name, path := range texturePaths {
+		game.textures.RequestTexture(name, path)
+	}
+	for name, size := range renderTargetSizes {
+		game.textures.RequestRenderTarget(name, size)
+	}
+}
 
 func (game *Game) Update() error {
-	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 nil
 	}
-	game.ebiten.Update()
+	game.input.Update(game.gameContext)
 	game.sceneManager.Update(&GameState{
 		SceneManager: game.sceneManager,
-		Input:        game.ebiten,
+		Input:        game.input,
 	})
 	return nil
 }
 
-func (game *Game) Draw(context ebiten.GraphicsContext) error {
+func (game *Game) Draw(g ebiten.GraphicsContext) error {
 	if !game.isInitialized() {
 		return nil
 	}
-	game.sceneManager.Draw(context, game.textures)
+	game.sceneManager.Draw(g, game.textures)
 	return nil
 }

example/blocks/input.go

@@ -38,9 +38,9 @@ func (i *Input) StateForKey(key ebiten.Key) int {
 	return i.states[key]
 }
 
-func (i *Input) Update() {
+func (i *Input) Update(g ebiten.GameContext) {
 	for key := range i.states {
-		if !ebiten.IsKeyPressed(key) {
+		if !g.IsKeyPressed(key) {
 			i.states[key] = 0
 			continue
 		}

example/blocks/textures.go

@@ -35,6 +35,7 @@ type nameSize struct {
 }
 
 type Textures struct {
+	gameContext       ebiten.GameContext
 	texturePaths      chan namePath
 	renderTargetSizes chan nameSize
 	textures          map[string]ebiten.TextureID
@@ -42,8 +43,9 @@ type Textures struct {
 	sync.RWMutex
 }
 
-func NewTextures() *Textures {
+func NewTextures(g ebiten.GameContext) *Textures {
 	textures := &Textures{
+		gameContext:       g,
 		texturePaths:      make(chan namePath),
 		renderTargetSizes: make(chan nameSize),
 		textures:          map[string]ebiten.TextureID{},
@@ -81,7 +83,7 @@ func (t *Textures) loopMain() {
 			if err != nil {
 				panic(err)
 			}
-			id, err := ebiten.NewTextureID(img, ebiten.FilterNearest)
+			id, err := t.gameContext.NewTextureID(img, ebiten.FilterNearest)
 			if err != nil {
 				panic(err)
 			}
@@ -93,7 +95,7 @@ func (t *Textures) loopMain() {
 		name := s.name
 		size := s.size
 		go func() {
-			id, err := ebiten.NewRenderTargetID(size.Width, size.Height, ebiten.FilterNearest)
+			id, err := t.gameContext.NewRenderTargetID(size.Width, size.Height, ebiten.FilterNearest)
 			if err != nil {
 				panic(err)
 			}

gamecontext.go

@@ -20,6 +20,12 @@ import (
 	"image"
 )
 
+type Game interface {
+	Initialize(g GameContext)
+	Update() error
+	Draw(gr GraphicsContext) error
+}
+
 type GameContext interface {
 	IsKeyPressed(key Key) bool
 	CursorPosition() (x, y int)
@@ -27,9 +33,3 @@ type GameContext interface {
 	NewRenderTargetID(width, height int, filter Filter) (RenderTargetID, error)
 	NewTextureID(img image.Image, filter Filter) (TextureID, error)
 }
-
-var currentGameContext GameContext
-
-func SetGameContext(g GameContext) {
-	currentGameContext = g
-}

graphics.go

@@ -50,7 +50,33 @@ type GraphicsContext interface {
 	Fill(r, g, b uint8)
 	Texture(id TextureID) Drawer
 	RenderTarget(id RenderTargetID) Drawer
-
 	ResetOffscreen()
 	SetOffscreen(id RenderTargetID)
 }
+
+// Filter represents the type of filter to be used when a texture or a render
+// target is maginified or minified.
+type Filter int
+
+const (
+	FilterNearest Filter = iota
+	FilterLinear
+)
+
+// TextureID represents an ID of a texture.
+type TextureID int
+
+// IsNil returns true if the texture is nil.
+func (i TextureID) IsNil() bool {
+	return i == 0
+}
+
+// RenderTargetID represents an ID of a render target.
+// A render target is essentially same as a texture, but it is assumed that the
+// all alpha of a render target is maximum.
+type RenderTargetID int
+
+// IsNil returns true if the render target is nil.
+func (i RenderTargetID) IsNil() bool {
+	return i == 0
+}

input.go

@@ -36,24 +36,3 @@ const (
 	MouseButtonMiddle
 	MouseButtonMax
 )
-
-func IsKeyPressed(key Key) bool {
-	if currentGameContext == nil {
-		panic("ebiten.IsKeyPressed: currentGameContext is not set")
-	}
-	return currentGameContext.IsKeyPressed(key)
-}
-
-func CursorPosition() (x, y int) {
-	if currentGameContext == nil {
-		panic("ebiten.CurrentPosition: currentGameContext is not set")
-	}
-	return currentGameContext.CursorPosition()
-}
-
-func IsMouseButtonPressed(button MouseButton) bool {
-	if currentGameContext == nil {
-		panic("ebiten.IsMouseButtonPressed: currentGameContext is not set")
-	}
-	return currentGameContext.IsMouseButtonPressed(button)
-}

internal/glfw/canvas.go

@@ -32,11 +32,11 @@ type canvas struct {
 	funcsDone       chan struct{}
 }
 
-func (c *canvas) draw(d GraphicsContextDrawer) (err error) {
+func (c *canvas) draw(game ebiten.Game) (err error) {
 	c.use(func() {
 		c.graphicsContext.PreUpdate()
 	})
-	if err = d.Draw(&graphicsContext{c}); err != nil {
+	if err = game.Draw(&graphicsContext{c}); err != nil {
 		return
 	}
 	c.use(func() {

internal/glfw/ui.go

@@ -30,15 +30,11 @@ func init() {
 	})
 }
 
-type GraphicsContextDrawer interface {
-	Draw(d ebiten.GraphicsContext) error
-}
-
 type UI struct {
 	canvas *canvas
 }
 
-func (u *UI) Start(width, height, scale int, title string) error {
+func (u *UI) Start(game ebiten.Game, width, height, scale int, title string) error {
 	if !glfw.Init() {
 		return errors.New("glfw.Init() fails")
 	}
@@ -53,7 +49,6 @@ func (u *UI) Start(width, height, scale int, title string) error {
 		funcs:     make(chan func()),
 		funcsDone: make(chan struct{}),
 	}
-	ebiten.SetGameContext(c)
 
 	c.run(width, height, scale)
 
@@ -68,6 +63,7 @@ func (u *UI) Start(width, height, scale int, title string) error {
 	}
 
 	u.canvas = c
+	game.Initialize(c)
 
 	return nil
 }
@@ -81,10 +77,10 @@ func (u *UI) Terminate() {
 	glfw.Terminate()
 }
 
-func (u *UI) Draw(drawer GraphicsContextDrawer) error {
-	return u.canvas.draw(drawer)
-}
-
 func (u *UI) IsClosed() bool {
 	return u.canvas.isClosed()
 }
+
+func (u *UI) DrawGame(game ebiten.Game) error {
+	return u.canvas.draw(game)
+}

runner/run.go

@@ -25,26 +25,19 @@ import (
 	"time"
 )
 
-type Game interface {
+// Run runs the game.
-	Update() error
+func Run(game ebiten.Game, width, height, scale int, title string, fps int) error {
-	Draw(context ebiten.GraphicsContext) error
-}
-
-// Run runs the game. Basically, this function executes ui.Start() at the start,
-// calls ui.DoEvent(), game.Update() and game.Draw() at a regular interval, and finally
-// calls ui.Terminate().
-func Run(game Game, width, height, scale int, title string, fps int) error {
 	ui := new(glfw.UI)
-	if err := ui.Start(width, height, scale, title); err != nil {
+	if err := ui.Start(game, width, height, scale, title); err != nil {
 		return err
 	}
+	defer ui.Terminate()
 
 	frameTime := time.Duration(int64(time.Second) / int64(fps))
 	tick := time.Tick(frameTime)
 	sigterm := make(chan os.Signal, 1)
 	signal.Notify(sigterm, os.Interrupt, syscall.SIGTERM)
 
-	defer ui.Terminate()
 	for {
 		ui.DoEvents()
 		if ui.IsClosed() {
@@ -52,7 +45,7 @@ func Run(game Game, width, height, scale int, title string, fps int) error {
 		}
 		select {
 		default:
-			if err := ui.Draw(game); err != nil {
+			if err := ui.DrawGame(game); err != nil {
 				return err
 			}
 		case <-tick:

texturefactory.go

@@ -1,64 +0,0 @@
-/*
-Copyright 2014 Hajime Hoshi
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package ebiten
-
-import (
-	"image"
-)
-
-// Filter represents the type of filter to be used when a texture or a render
-// target is maginified or minified.
-type Filter int
-
-const (
-	FilterNearest Filter = iota
-	FilterLinear
-)
-
-// TextureID represents an ID of a texture.
-type TextureID int
-
-// IsNil returns true if the texture is nil.
-func (i TextureID) IsNil() bool {
-	return i == 0
-}
-
-// RenderTargetID represents an ID of a render target.
-// A render target is essentially same as a texture, but it is assumed that the
-// all alpha of a render target is maximum.
-type RenderTargetID int
-
-// IsNil returns true if the render target is nil.
-func (i RenderTargetID) IsNil() bool {
-	return i == 0
-}
-
-// NewRenderTargetID returns an ID of a newly created render target.
-func NewRenderTargetID(width, height int, filter Filter) (RenderTargetID, error) {
-	if currentGameContext == nil {
-		panic("graphics.NewRenderTarget: currentGameContext is not set.")
-	}
-	return currentGameContext.NewRenderTargetID(width, height, filter)
-}
-
-// NewRenderTargetID returns an ID of a newly created texture.
-func NewTextureID(img image.Image, filter Filter) (TextureID, error) {
-	if currentGameContext == nil {
-		panic("graphics.NewTexture: currentGameContext is not set")
-	}
-	return currentGameContext.NewTextureID(img, filter)
-}