Add SetScreenSize

example/windowsize/main.go

@@ -0,0 +1,85 @@
+// Copyright 2015 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 main
+
+import (
+	"github.com/hajimehoshi/ebiten"
+	"github.com/hajimehoshi/ebiten/ebitenutil"
+	_ "image/jpeg"
+	"log"
+)
+
+const (
+	initScreenWidth  = 320
+	initScreenHeight = 240
+)
+
+var (
+	gophersImage *ebiten.Image
+	screenWidth  = initScreenWidth
+	screenHeight = initScreenHeight
+	keyStates    = map[ebiten.Key]int{
+		ebiten.KeyUp:    0,
+		ebiten.KeyDown:  0,
+		ebiten.KeyLeft:  0,
+		ebiten.KeyRight: 0,
+	}
+)
+
+func update(screen *ebiten.Image) error {
+	for key, _ := range keyStates {
+		if !ebiten.IsKeyPressed(key) {
+			keyStates[key] = 0
+			continue
+		}
+		keyStates[key]++
+	}
+
+	if keyStates[ebiten.KeyUp] == 1 {
+		screenHeight += 16
+	}
+	if keyStates[ebiten.KeyDown] == 1 {
+		screenHeight -= 16
+	}
+	if keyStates[ebiten.KeyLeft] == 1 {
+		screenWidth -= 16
+	}
+	if keyStates[ebiten.KeyRight] == 1 {
+		screenWidth += 16
+	}
+	ebiten.SetScreenSize(screenWidth, screenHeight)
+
+	w, h := gophersImage.Size()
+	w2, h2 := screen.Size()
+	op := &ebiten.DrawImageOptions{}
+	op.GeoM.Translate(float64(-w+w2)/2, float64(-h+h2)/2)
+	if err := screen.DrawImage(gophersImage, op); err != nil {
+		return err
+	}
+
+	ebitenutil.DebugPrint(screen, "Press arrow keys")
+	return nil
+}
+
+func main() {
+	var err error
+	gophersImage, _, err = ebitenutil.NewImageFromFile("images/gophers.jpg", ebiten.FilterNearest)
+	if err != nil {
+		log.Fatal(err)
+	}
+	if err := ebiten.Run(update, initScreenWidth, initScreenHeight, 2, "Window Size (Ebiten Demo)"); err != nil {
+		log.Fatal(err)
+	}
+}

graphicscontext.go

@@ -26,45 +26,20 @@ func useGLContext(f func(*opengl.Context)) {
 	})
 }
 
-func newGraphicsContext(c *opengl.Context, screenWidth, screenHeight, screenScale int) (*graphicsContext, error) {
-	f, err := graphics.NewZeroFramebuffer(c, screenWidth*screenScale, screenHeight*screenScale)
-	if err != nil {
+func newGraphicsContext(screenWidth, screenHeight, screenScale int) (*graphicsContext, error) {
+	c := &graphicsContext{}
+	if err := c.setSize(screenWidth, screenHeight, screenScale); err != nil {
 		return nil, err
 	}
-
-	texture, err := graphics.NewTexture(c, screenWidth, screenHeight, c.Nearest)
-	if err != nil {
-		return nil, err
-	}
-	screenF, err := graphics.NewFramebufferFromTexture(c, texture)
-	if err != nil {
-		return nil, err
-	}
-	screen := &Image{framebuffer: screenF, texture: texture}
-	return &graphicsContext{
-		glContext:   c,
-		defaultR:    &Image{framebuffer: f, texture: nil},
-		screen:      screen,
-		screenScale: screenScale,
-	}, nil
+	return c, nil
 }
 
 type graphicsContext struct {
-	glContext   *opengl.Context
 	screen      *Image
 	defaultR    *Image
 	screenScale int
 }
 
-func (c *graphicsContext) dispose() {
-	// NOTE: Now this method is not used anywhere.
-	framebuffer := c.screen.framebuffer
-	texture := c.screen.texture
-
-	framebuffer.Dispose(c.glContext)
-	texture.Dispose(c.glContext)
-}
-
 func (c *graphicsContext) preUpdate() error {
 	return c.screen.Clear()
 }
@@ -82,3 +57,34 @@ func (c *graphicsContext) postUpdate() error {
 	}
 	return nil
 }
+
+func (c *graphicsContext) setSize(screenWidth, screenHeight, screenScale int) error {
+	if c.defaultR != nil {
+		c.defaultR.dispose()
+	}
+	if c.screen != nil {
+		c.screen.dispose()
+	}
+
+	var err error
+	useGLContext(func(g *opengl.Context) {
+		f, err := graphics.NewZeroFramebuffer(g, screenWidth*screenScale, screenHeight*screenScale)
+		if err != nil {
+			return
+		}
+
+		texture, err := graphics.NewTexture(g, screenWidth, screenHeight, g.Nearest)
+		if err != nil {
+			return
+		}
+		screenF, err := graphics.NewFramebufferFromTexture(g, texture)
+		if err != nil {
+			return
+		}
+		screen := &Image{framebuffer: screenF, texture: texture}
+		c.defaultR = &Image{framebuffer: f, texture: nil}
+		c.screen = screen
+		c.screenScale = screenScale
+	})
+	return err
+}

image.go

@@ -169,6 +169,18 @@ func (i *Image) At(x, y int) color.Color {
 	return color.RGBA{r, g, b, a}
 }
 
+func (i *Image) dispose() {
+	useGLContext(func(c *opengl.Context) {
+		if i.framebuffer != nil {
+			i.framebuffer.Dispose(c)
+		}
+		if i.texture != nil {
+			i.texture.Dispose(c)
+		}
+	})
+	i.pixels = nil
+}
+
 // ReplacePixels replaces the pixels of the image with p.
 //
 // The given p must represent RGBA pre-multiplied alpha values. len(p) must equal to 4 * (image width) * (image height).

internal/graphics/framebuffer.go

@@ -85,6 +85,10 @@ func (f *Framebuffer) Size() (width, height int) {
 }
 
 func (f *Framebuffer) Dispose(c *opengl.Context) {
+	// Don't delete the default framebuffer.
+	if f.native == opengl.ZeroFramebuffer {
+		return
+	}
 	c.DeleteFramebuffer(f.native)
 }
 

internal/graphics/internal/opengl/context.go

@@ -28,6 +28,8 @@ type Shader uint32
 type Program uint32
 type Buffer uint32
 
+var ZeroFramebuffer Framebuffer = 0
+
 // TODO: Remove this after the GopherJS bug was fixed (#159)
 func (p Program) Equals(other Program) bool {
 	return p == other

internal/graphics/internal/opengl/context_js.go

@@ -31,6 +31,8 @@ type Framebuffer struct {
 	js.Object
 }
 
+var ZeroFramebuffer Framebuffer
+
 type Shader struct {
 	js.Object
 }

internal/ui/ui_glfw.go

@@ -37,6 +37,7 @@ func Init() {
 	glfw.WindowHint(glfw.Visible, glfw.False)
 	glfw.WindowHint(glfw.Resizable, glfw.False)
 
+	// As start, create an window with temporary size to create OpenGL context thread.
 	window, err := glfw.CreateWindow(16, 16, "", nil, nil)
 	if err != nil {
 		panic(err)
@@ -87,9 +88,17 @@ func SwapBuffers() {
 	currentUI.swapBuffers()
 }
 
+func SetScreenSize(width, height int) (bool, int) {
+	result := currentUI.setScreenSize(width, height, currentUI.scale)
+	return result, currentUI.actualScale
+}
+
 type userInterface struct {
 	window      *glfw.Window
+	width       int
+	height      int
 	scale       int
+	actualScale int
 	funcs       chan func()
 }
 
@@ -105,37 +114,12 @@ func (u *userInterface) start(width, height, scale int, title string) (actualSca
 	x := (videoMode.Width - width*scale) / 2
 	y := (videoMode.Height - height*scale) / 3
 
-	ch := make(chan struct{})
-	window := u.window
-	window.SetFramebufferSizeCallback(func(w *glfw.Window, width, height int) {
-		window.SetFramebufferSizeCallback(nil)
-		close(ch)
-	})
-	window.SetSize(width*scale, height*scale)
-	window.SetTitle(title)
-	window.SetPosition(x, y)
-	window.Show()
+	u.setScreenSize(width, height, scale)
+	u.window.SetTitle(title)
+	u.window.SetPosition(x, y)
+	u.window.Show()
 
-	for {
-		done := false
-		glfw.PollEvents()
-		select {
-		case <-ch:
-			done = true
-		default:
-		}
-		if done {
-			break
-		}
-	}
-
-	u.scale = scale
-
-	// For retina displays, recalculate the scale with the framebuffer size.
-	windowWidth, _ := window.GetFramebufferSize()
-	actualScale = windowWidth / width
-
-	return actualScale, nil
+	return u.actualScale, nil
 }
 
 func (u *userInterface) pollEvents() error {
@@ -167,3 +151,38 @@ func (u *userInterface) isClosed() bool {
 func (u *userInterface) swapBuffers() {
 	u.window.SwapBuffers()
 }
+
+func (u *userInterface) setScreenSize(width, height, scale int) bool {
+	if u.width == width && u.height == height && u.scale == scale {
+		return false
+	}
+
+	ch := make(chan struct{})
+	window := u.window
+	window.SetFramebufferSizeCallback(func(w *glfw.Window, width, height int) {
+		window.SetFramebufferSizeCallback(nil)
+		close(ch)
+	})
+	window.SetSize(width*scale, height*scale)
+
+	for {
+		done := false
+		glfw.PollEvents()
+		select {
+		case <-ch:
+			done = true
+		default:
+		}
+		if done {
+			break
+		}
+	}
+	u.width = width
+	u.height = height
+	u.scale = scale
+
+	// For retina displays, recalculate the scale with the framebuffer size.
+	windowWidth, _ := window.GetFramebufferSize()
+	u.actualScale = windowWidth / width
+	return true
+}

internal/ui/ui_js.go

@@ -45,6 +45,13 @@ func SwapBuffers() {
 	currentUI.swapBuffers()
 }
 
+func SetScreenSize(width, height int) (bool, int) {
+	scale := canvas.Get("dataset").Get("ebitenScale").Int()
+	result := currentUI.setScreenSize(width, height, scale)
+	actualScale := canvas.Get("dataset").Get("ebitenActualScale").Int()
+	return result, actualScale
+}
+
 var canvas js.Object
 
 type userInterface struct{}
@@ -211,13 +218,32 @@ func devicePixelRatio() int {
 	return ratio
 }
 
-func (*userInterface) start(width, height, scale int, title string) (actualScale int, err error) {
+func (u *userInterface) start(width, height, scale int, title string) (actualScale int, err error) {
 	doc := js.Global.Get("document")
 	doc.Set("title", title)
-	actualScale = scale * devicePixelRatio()
+	u.setScreenSize(width, height, scale)
+	canvas.Call("focus")
+
+	actualScale = canvas.Get("dataset").Get("ebitenActualScale").Int()
+	return actualScale, nil
+}
+
+func (*userInterface) setScreenSize(width, height, scale int) bool {
+	a := canvas.Get("dataset").Get("ebitenActualScale").Int()
+	if a != 0 {
+		w := canvas.Get("width").Int() / a
+		h := canvas.Get("height").Int() / a
+		s := canvas.Get("dataset").Get("ebitenScale").Int()
+		if w == width && h == height && s == scale {
+			return false
+		}
+	}
+
+	actualScale := scale * devicePixelRatio()
 	canvas.Set("width", width*actualScale)
 	canvas.Set("height", height*actualScale)
 	canvas.Get("dataset").Set("ebitenScale", scale)
+	canvas.Get("dataset").Set("ebitenActualScale", actualScale)
 	canvasStyle := canvas.Get("style")
 
 	cssWidth := width * scale
@@ -227,8 +253,5 @@ func (*userInterface) start(width, height, scale int, title string) (actualScale
 	// CSS calc requires space chars.
 	canvasStyle.Set("left", "calc(50% - "+strconv.Itoa(cssWidth/2)+"px)")
 	canvasStyle.Set("top", "calc(50% - "+strconv.Itoa(cssHeight/2)+"px)")
-
-	canvas.Call("focus")
-
-	return actualScale, nil
+	return true
 }

run.go

@@ -16,16 +16,20 @@ package ebiten
 
 import (
 	audio "github.com/hajimehoshi/ebiten/exp/audio/internal"
-	"github.com/hajimehoshi/ebiten/internal/graphics/internal/opengl"
 	"github.com/hajimehoshi/ebiten/internal/ui"
 	"time"
 )
 
-var fps = 0.0
+var runContext = &struct {
+	running         bool
+	fps             float64
+	newScreenWidth  int
+	newScreenHeight int
+}{}
 
 // CurrentFPS returns the current number of frames per second.
 func CurrentFPS() float64 {
-	return fps
+	return runContext.fps
 }
 
 // Run runs the game.
@@ -38,16 +42,15 @@ func CurrentFPS() float64 {
 // but this is not strictly guaranteed.
 // If you need to care about time, you need to check current time every time f is called.
 func Run(f func(*Image) error, width, height, scale int, title string) error {
+	runContext.running = true
+
 	actualScale, err := ui.Start(width, height, scale, title)
 	if err != nil {
 		return err
 	}
 	defer ui.Terminate()
 
-	var graphicsContext *graphicsContext
-	useGLContext(func(c *opengl.Context) {
-		graphicsContext, err = newGraphicsContext(c, width, height, actualScale)
-	})
+	graphicsContext, err := newGraphicsContext(width, height, actualScale)
 	if err != nil {
 		return err
 	}
@@ -55,6 +58,18 @@ func Run(f func(*Image) error, width, height, scale int, title string) error {
 	frames := 0
 	t := time.Now().UnixNano()
 	for {
+		if 0 < runContext.newScreenWidth || 0 < runContext.newScreenHeight {
+			changed, actualScale := ui.SetScreenSize(runContext.newScreenWidth, runContext.newScreenHeight)
+			if changed {
+				w, h := runContext.newScreenWidth, runContext.newScreenHeight
+				if err := graphicsContext.setSize(w, h, actualScale); err != nil {
+					return err
+				}
+			}
+		}
+		runContext.newScreenWidth = 0
+		runContext.newScreenHeight = 0
+
 		if err := ui.DoEvents(); err != nil {
 			return err
 		}
@@ -81,9 +96,23 @@ func Run(f func(*Image) error, width, height, scale int, title string) error {
 		now := time.Now().UnixNano()
 		frames++
 		if time.Second <= time.Duration(now-t) {
-			fps = float64(frames) * float64(time.Second) / float64(now-t)
+			runContext.fps = float64(frames) * float64(time.Second) / float64(now-t)
 			t = now
 			frames = 0
 		}
 	}
 }
+
+// SetScreenSize changes the (logical) size of the screen.
+// This doesn't affect the current scale of the screen.
+func SetScreenSize(width, height int) {
+	if !runContext.running {
+		panic("SetScreenSize must be called during Run")
+	}
+	runContext.newScreenWidth = width
+	runContext.newScreenHeight = height
+}
+
+// TODO: Create SetScreenPosition (for GLFW)
+
+// TODO: Create SetScreenScale