ebiten: Remove the argument from Update

Fixes #1260

doc.go

@@ -21,7 +21,7 @@
 //
 //     // Update proceeds the game state.
 //     // Update is called every tick (1/60 [s] by default).
-//     func (g *Game) Update(screen *ebiten.Image) error {
+//     func (g *Game) Update() error {
 //         // Write your game's logical update.
 //         return nil
 //     }

examples/2048/2048/game.go

@@ -57,7 +57,7 @@ func (g *Game) Layout(outsideWidth, outsideHeight int) (screenWidth, screenHeigh
 }
 
 // Update updates the current game state.
-func (g *Game) Update(*ebiten.Image) error {
+func (g *Game) Update() error {
 	g.input.Update()
 	if err := g.board.Update(g.input); err != nil {
 		return err

examples/additive/main.go

@@ -38,7 +38,7 @@ var (
 
 type Game struct{}
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	return nil
 }
 

examples/address/main.go

@@ -104,7 +104,7 @@ func drawRect(screen *ebiten.Image, img *ebiten.Image, x, y, width, height float
 
 type Game struct{}
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	return nil
 }
 

examples/airship/main.go

@@ -241,7 +241,7 @@ func NewGame() *Game {
 	}
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	// Manipulate the player by the input.
 	if ebiten.IsKeyPressed(ebiten.KeySpace) {
 		g.player.MoveForward()

examples/alphablending/main.go

@@ -40,7 +40,7 @@ type Game struct {
 	count int
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.count++
 	g.count %= ebiten.MaxTPS() * 10
 	return nil

examples/animation/main.go

@@ -45,7 +45,7 @@ type Game struct {
 	count int
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.count++
 	return nil
 }

examples/audio/main.go

@@ -284,7 +284,7 @@ func NewGame() (*Game, error) {
 	}, nil
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	select {
 	case p := <-g.musicPlayerCh:
 		g.musicPlayer = p

examples/audioinfiniteloop/main.go

@@ -51,7 +51,7 @@ type Game struct {
 	player *audio.Player
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if g.player != nil {
 		return nil
 	}

examples/audiopanning/main.go

@@ -94,7 +94,7 @@ func lerp(a, b, t float64) float64 {
 	return a*(1-t) + b*t
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.initAudio()
 	g.count++
 	r := float64(g.count) * ((1.0 / 60.0) * 2 * math.Pi) * 0.1 // full cycle every 10 seconds

examples/blocks/blocks/game.go

@@ -32,7 +32,7 @@ func (g *Game) Layout(outsideWidth, outsideHeight int) (screenWidth, screenHeigh
 	return ScreenWidth, ScreenHeight
 }
 
-func (g *Game) Update(*ebiten.Image) error {
+func (g *Game) Update() error {
 	if g.sceneManager == nil {
 		g.sceneManager = &SceneManager{}
 		g.sceneManager.GoTo(&TitleScene{})

examples/blur/main.go

@@ -37,7 +37,7 @@ var (
 
 type Game struct{}
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	return nil
 }
 

examples/camera/main.go

@@ -133,7 +133,7 @@ type Game struct {
 	camera Camera
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if ebiten.IsKeyPressed(ebiten.KeyA) || ebiten.IsKeyPressed(ebiten.KeyLeft) {
 		g.camera.Position[0] -= 1
 	}

examples/chipmunk/main.go

@@ -90,7 +90,7 @@ func NewGame() *Game {
 	}
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.space.Step(1.0 / float64(ebiten.MaxTPS()))
 	return nil
 }

examples/contextlost/main.go

@@ -78,7 +78,7 @@ func (g *Game) loseAndRestoreContext(context js.Value) {
 	}()
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if inpututil.IsKeyJustPressed(ebiten.KeySpace) {
 		doc := js.Global().Get("document")
 		canvas := doc.Call("getElementsByTagName", "canvas").Index(0)

examples/doomfire/main.go

@@ -125,7 +125,7 @@ func (g *Game) renderFire() {
 	}
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.updateFirePixels()
 	return nil
 }

examples/drag/main.go

@@ -266,7 +266,7 @@ func (g *Game) updateStroke(stroke *Stroke) {
 	stroke.SetDraggingObject(nil)
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if inpututil.IsMouseButtonJustPressed(ebiten.MouseButtonLeft) {
 		s := NewStroke(&MouseStrokeSource{})
 		s.SetDraggingObject(g.spriteAt(s.Position()))

examples/filter/main.go

@@ -39,7 +39,7 @@ var (
 type Game struct {
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	return nil
 }
 

examples/flappy/main.go

@@ -203,7 +203,7 @@ func (g *Game) Layout(outsideWidth, outsideHeight int) (int, int) {
 	return screenWidth, screenHeight
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	switch g.mode {
 	case ModeTitle:
 		if jump() {

examples/flood/main.go

@@ -49,7 +49,7 @@ var (
 type Game struct {
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	return nil
 }
 

examples/font/main.go

@@ -124,7 +124,7 @@ type Game struct {
 	kanjiTextColor color.RGBA
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	// Change the text color for each second.
 	if g.counter%ebiten.MaxTPS() == 0 {
 		g.kanjiText = nil

examples/fullscreen/main.go

@@ -79,7 +79,7 @@ type Game struct {
 	count int
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.count++
 
 	if ebiten.IsKeyPressed(ebiten.KeyQ) {

examples/gamepad/main.go

@@ -39,7 +39,7 @@ type Game struct {
 	pressedButtons map[int][]string
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if g.gamepadIDs == nil {
 		g.gamepadIDs = map[int]struct{}{}
 	}

examples/highdpi/main.go

@@ -49,7 +49,7 @@ type Game struct {
 	highDPIImage *ebiten.Image
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	// TODO: DeviceScaleFactor() might return different values for different monitors.
 	// Add a mode to adjust the screen size along with the current device scale (#705).
 	// Now this example uses the device scale initialized at the beginning of this application.

examples/hsv/main.go

@@ -68,7 +68,7 @@ func NewGame() *Game {
 	}
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	// Adjust HSV values along with the user's input.
 	if ebiten.IsKeyPressed(ebiten.KeyQ) {
 		g.hue128--

examples/hue/main.go

@@ -40,7 +40,7 @@ type Game struct {
 	count int
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.count++
 	return nil
 }

examples/infinitescroll/main.go

@@ -78,7 +78,7 @@ type Game struct {
 	viewport viewport
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.viewport.Move()
 	return nil
 }

examples/keyboard/main.go

@@ -49,7 +49,7 @@ type Game struct {
 	pressed []ebiten.Key
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.pressed = nil
 	for k := ebiten.Key(0); k <= ebiten.KeyMax; k++ {
 		if ebiten.IsKeyPressed(k) {

examples/life/main.go

@@ -160,7 +160,7 @@ type Game struct {
 	pixels []byte
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.world.Update()
 	return nil
 }

examples/mandelbrot/main.go

@@ -81,7 +81,7 @@ func init() {
 type Game struct {
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	return nil
 }
 

examples/mascot/main.go

@@ -87,7 +87,7 @@ func (m *mascot) Layout(outsideWidth, outsideHeight int) (int, int) {
 	return width, height
 }
 
-func (m *mascot) Update(screen *ebiten.Image) error {
+func (m *mascot) Update() error {
 	m.count++
 
 	sw, sh := ebiten.ScreenSizeInFullscreen()

examples/masking/main.go

@@ -96,7 +96,7 @@ func NewGame() *Game {
 	}
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if g.spotLightVX == 0 {
 		g.spotLightVX = 1
 	}

examples/minify/main.go

@@ -48,7 +48,7 @@ type Game struct {
 	counter int
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.counter++
 	if g.counter == 480 {
 		g.counter = 0

examples/moire/main.go

@@ -66,7 +66,7 @@ func (g *game) Layout(outsideWidth, outsideHeight int) (int, int) {
 	return screenWidth, screenHeight
 }
 
-func (g *game) Update(screen *ebiten.Image) error {
+func (g *game) Update() error {
 	fullscreen := ebiten.IsFullscreen()
 
 	if inpututil.IsKeyJustPressed(ebiten.KeyS) {

examples/mosaic/main.go

@@ -58,7 +58,7 @@ func init() {
 type Game struct {
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	return nil
 }
 

examples/noise/main.go

@@ -49,7 +49,7 @@ type Game struct {
 	noiseImage *image.RGBA
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	// Generate the noise with random RGB values.
 	const l = screenWidth * screenHeight
 	for i := 0; i < l; i++ {

examples/paint/main.go

@@ -63,7 +63,7 @@ type Game struct {
 	count int
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	drawn := false
 
 	// Paint the brush by mouse dragging

examples/particles/main.go

@@ -141,7 +141,7 @@ type Game struct {
 	sprites *list.List
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if g.sprites == nil {
 		g.sprites = list.New()
 	}

examples/pcm/main.go

@@ -137,7 +137,7 @@ type Game struct {
 	currentNote rune
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	// Play notes for each half second.
 	if g.frames%30 == 0 && audioContext.IsReady() {
 		g.currentNote = playNote(g.scoreIndex)

examples/perspective/main.go

@@ -37,7 +37,7 @@ var (
 
 type Game struct{}
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	return nil
 }
 

examples/piano/main.go

@@ -207,7 +207,7 @@ var (
 type Game struct {
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	// The piano data is still being initialized.
 	// Get the progress if available.
 	if !pianoNoteSamplesInited {

examples/platformer/main.go

@@ -124,7 +124,7 @@ type Game struct {
 	gopher *char
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if g.gopher == nil {
 		g.gopher = &char{x: 50 * unit, y: groundY * unit}
 	}

examples/polygons/main.go

@@ -98,7 +98,7 @@ type Game struct {
 	prevNgon int
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if inpututil.IsKeyJustPressed(ebiten.KeyLeft) {
 		g.ngon--
 		if g.ngon < 1 {

examples/raycasting/main.go

@@ -221,7 +221,7 @@ type Game struct {
 	objects  []object
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if inpututil.IsKeyJustPressed(ebiten.KeyEscape) {
 		return errors.New("game ended by player")
 	}

examples/rotate/main.go

@@ -40,7 +40,7 @@ type Game struct {
 	count int
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.count++
 	return nil
 }

examples/set/main.go

@@ -45,7 +45,7 @@ func init() {
 type Game struct {
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	w, h := offscreen.Size()
 	x := rand.Intn(w)
 	y := rand.Intn(h)

examples/shader/main.go

@@ -96,7 +96,7 @@ type Game struct {
 	time    int
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.time++
 	if inpututil.IsKeyJustPressed(ebiten.KeyDown) {
 		g.idx++

examples/shapes/main.go

@@ -154,7 +154,7 @@ func rect(x, y, w, h float32, clr color.RGBA) ([]ebiten.Vertex, []uint16) {
 	}, []uint16{0, 1, 2, 1, 2, 3}
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.count++
 	g.count %= 240
 	return nil

examples/sinewave/main.go

@@ -97,7 +97,7 @@ type Game struct {
 	player *audio.Player
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if g.player == nil {
 		// Pass the (infinite) stream to audio.NewPlayer.
 		// After calling Play, the stream never ends as long as the player object lives.

examples/snake/main.go

@@ -102,7 +102,7 @@ func (g *Game) reset() {
 	g.moveDirection = dirNone
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if inpututil.IsKeyJustPressed(ebiten.KeyLeft) || inpututil.IsKeyJustPressed(ebiten.KeyA) {
 		if g.moveDirection != dirRight {
 			g.moveDirection = dirLeft

examples/sprites/main.go

@@ -163,7 +163,7 @@ func rightTouched() bool {
 	return false
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if !g.inited {
 		g.init()
 	}

examples/spriteshd/main.go

@@ -145,7 +145,7 @@ func (g *Game) init() {
 
 var regularTermination = errors.New("regular termination")
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if !g.inited {
 		g.init()
 	}

examples/squiral/main.go

@@ -289,7 +289,7 @@ func init() {
 
 type Game struct{}
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	reset := false
 
 	if inpututil.IsKeyJustPressed(ebiten.KeyB) {

examples/text/main.go

@@ -79,7 +79,7 @@ type Game struct {
 	kanjiTextColor color.RGBA
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	return nil
 }
 

examples/tiles/main.go

@@ -63,7 +63,7 @@ type Game struct {
 	layers [][]int
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	return nil
 }
 

examples/typewriter/main.go

@@ -51,7 +51,7 @@ type Game struct {
 	counter int
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	// Add a string from InputChars, that returns string input by users.
 	// Note that InputChars result changes every frame, so you need to call this
 	// every frame.

examples/ui/main.go

@@ -490,7 +490,7 @@ func init() {
 	})
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.button1.Update()
 	g.button2.Update()
 	g.checkBox.Update()

examples/vector/main.go

@@ -175,7 +175,7 @@ type Game struct {
 	counter int
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	g.counter++
 	return nil
 }

examples/wav/main.go

@@ -74,7 +74,7 @@ func init() {
 	}
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	if ebiten.IsKeyPressed(ebiten.KeyP) && !g.audioPlayer.IsPlaying() {
 		// As audioPlayer has one stream and remembers the playing position,
 		// rewinding is needed before playing when reusing audioPlayer.

examples/wheel/main.go

@@ -42,7 +42,7 @@ type Game struct {
 	y float64
 }
 
-func (g *Game) Update(screen *ebiten.Image) error {
+func (g *Game) Update() error {
 	dx, dy := ebiten.Wheel()
 	g.x += dx
 	g.y += dy

examples/windowsize/main.go

@@ -97,7 +97,7 @@ func (g *game) Layout(outsideWidth, outsideHeight int) (int, int) {
 	return g.width, g.height
 }
 
-func (g *game) Update(screen *ebiten.Image) error {
+func (g *game) Update() error {
 	var (
 		screenWidth  int
 		screenHeight int

imagedumper_desktop.go

@@ -84,7 +84,7 @@ func dumpInternalImages() error {
 }
 
 type imageDumper struct {
-	f func(screen *Image) error
+	g Game
 
 	keyState map[Key]int
 
@@ -95,15 +95,21 @@ type imageDumper struct {
 	hasDumpInternalImagesKey bool
 	dumpInternalImagesKey    Key
 	toDumpInternalImages     bool
+
+	err error
 }
 
-func (i *imageDumper) update(screen *Image) error {
+func (i *imageDumper) update() error {
+	if i.err != nil {
+		return i.err
+	}
+
 	const (
 		envScreenshotKey     = "EBITEN_SCREENSHOT_KEY"
 		envInternalImagesKey = "EBITEN_INTERNAL_IMAGES_KEY"
 	)
 
-	if err := i.f(screen); err != nil {
+	if err := i.g.Update(); err != nil {
 		return err
 	}
 
@@ -153,9 +159,7 @@ func (i *imageDumper) update(screen *Image) error {
 			i.keyState[key] = 0
 		}
 	}
-
+	return nil
-	// TODO: As the screen will be available only from Draw, move this to a drawing function.
-	return i.dump(screen)
 }
 
 func (i *imageDumper) dump(screen *Image) error {

imagedumper_notdesktop.go

@@ -17,11 +17,11 @@
 package ebiten
 
 type imageDumper struct {
-	f func(screen *Image) error
+	g Game
 }
 
-func (i *imageDumper) update(screen *Image) error {
+func (i *imageDumper) update() error {
-	return i.f(screen)
+	return i.g.Update()
 }
 
 func (i *imageDumper) dump(screen *Image) error {

internal/buffered/image_test.go

@@ -42,7 +42,7 @@ type game struct {
 	code  int
 }
 
-func (g *game) Update(*ebiten.Image) error {
+func (g *game) Update() error {
 	select {
 	case f := <-mainCh:
 		f()

internal/testing/testing.go

@@ -30,7 +30,7 @@ type game struct {
 	code int
 }
 
-func (g *game) Update(*ebiten.Image) error {
+func (g *game) Update() error {
 	g.code = g.m.Run()
 	return regularTermination
 }

run.go

@@ -25,20 +25,14 @@ import (
 type Game interface {
 	// Update updates a game by one tick. The given argument represents a screen image.
 	//
-	// Basically Update updates the game logic. Whether Update also draws the screen or not depends on the
-	// existence of Draw implementation.
-	//
-	// The Draw function's definition is:
-	//
-	//     Draw(screen *Image)
-	//
 	// Update updates only the game logic and Draw draws the screen.
-	// In this case, the argument screen's updated content by Update is not adopted for the actual game screen,
+	//
-	// and the screen's updated content by Draw is adopted instead.
 	// In the first frame, it is ensured that Update is called at least once before Draw. You can use Update
-	// to initialize the game state. After the first frame, Update might not be called or might be called once
+	// to initialize the game state.
+	//
+	// After the first frame, Update might not be called or might be called once
 	// or more for one frame. The frequency is determined by the current TPS (tick-per-second).
-	Update(screen *Image) error
+	Update() error
 
 	// Draw draws the game screen by one frame.
 	//
@@ -102,32 +96,20 @@ func IsScreenClearedEveryFrame() bool {
 	return atomic.LoadInt32(&isScreenClearedEveryFrame) != 0
 }
 
-type imageDumperGame struct {
+type imageDumperGameWithDraw struct {
 	game Game
 	d    *imageDumper
+	err  error
 }
 
-func (i *imageDumperGame) Update(screen *Image) error {
+func (i *imageDumperGameWithDraw) Update() error {
-	if i.d == nil {
-		i.d = &imageDumper{f: i.game.Update}
-	}
-	return i.d.update(screen)
-}
-
-func (i *imageDumperGame) Layout(outsideWidth, outsideHeight int) (screenWidth, screenHeight int) {
-	return i.game.Layout(outsideWidth, outsideHeight)
-}
-
-type imageDumperGameWithDraw struct {
-	imageDumperGame
-	err error
-}
-
-func (i *imageDumperGameWithDraw) Update(screen *Image) error {
 	if i.err != nil {
 		return i.err
 	}
-	return i.imageDumperGame.Update(screen)
+	if i.d == nil {
+		i.d = &imageDumper{g: i.game}
+	}
+	return i.d.update()
 }
 
 func (i *imageDumperGameWithDraw) Draw(screen *Image) {
@@ -136,14 +118,13 @@ func (i *imageDumperGameWithDraw) Draw(screen *Image) {
 	}
 
 	i.game.Draw(screen)
-
-	// Call dump explicitly. IsDrawingSkipped always returns true when Draw is defined.
-	if i.d == nil {
-		i.d = &imageDumper{f: i.game.Update}
-	}
 	i.err = i.d.dump(screen)
 }
 
+func (i *imageDumperGameWithDraw) Layout(outsideWidth, outsideHeight int) (screenWidth, screenHeight int) {
+	return i.game.Layout(outsideWidth, outsideHeight)
+}
+
 // RunGame starts the main loop and runs the game.
 // game's Update function is called every tick to update the game logic.
 // game's Draw function is, if it exists, called every frame to draw the screen.
@@ -188,7 +169,7 @@ func (i *imageDumperGameWithDraw) Draw(screen *Image) {
 func RunGame(game Game) error {
 	fixWindowPosition(WindowSize())
 	return runGame(&imageDumperGameWithDraw{
-		imageDumperGame: imageDumperGame{game: game},
+		game: game,
 	}, 0)
 }
 
@@ -211,7 +192,7 @@ func runGame(game Game, scale float64) error {
 func RunGameWithoutMainLoop(game Game) {
 	fixWindowPosition(WindowSize())
 	game = &imageDumperGameWithDraw{
-		imageDumperGame: imageDumperGame{game: game},
+		game: game,
 	}
 	theUIContext.set(game, 0)
 	uiDriver().RunWithoutMainLoop(theUIContext)

uicontext.go

@@ -194,13 +194,7 @@ func (c *uiContext) update() error {
 		if err := hooks.RunBeforeUpdateHooks(); err != nil {
 			return err
 		}
-
+		if err := c.game.Update(); err != nil {
-		// Multiple successive Clear call should be integrated into one graphics command, then
-		// calling Clear on every Update should not affect the performance.
-		if IsScreenClearedEveryFrame() {
-			c.offscreen.Clear()
-		}
-		if err := c.game.Update(c.offscreen); err != nil {
 			return err
 		}
 		uiDriver().ResetForFrame()