Remove dependency on internal/png on mobiles and browsers

Fixes #735

doc.go

@@ -40,11 +40,11 @@
 // The EBITEN_SCREENSHOT_KEY environment variable specifies the key
 // to take a screenshot. For example, if you run your game with
 // `EBITEN_SCREENSHOT_KEY=q`, you can take a game screen's screenshot
-// by pressing Q key.
+// by pressing Q key. This works only on desktops.
 //
 // The EBITEN_INTERNAL_IMAGES_KEY environment variable specifies the key
 // to dump all the internal images. This is valid only when the build tag
-// 'ebitendebug' is specified.
+// 'ebitendebug' is specified. This works only on desktops.
 //
 // In the API document, 'the main thread' means the goroutine in init(), main() and their callees without 'go'
 // statement. It is assured that 'the main thread' runs on the OS main thread. There are some Ebiten functions that

imagedumper_desktop.go

@@ -0,0 +1,213 @@
+// Copyright 2018 The Ebiten Authors
+//
+// 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.
+
+// +build !android
+// +build !js
+// +build !ios
+
+package ebiten
+
+import (
+	"fmt"
+	"image"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"time"
+
+	"github.com/hajimehoshi/ebiten/internal/png"
+	"github.com/hajimehoshi/ebiten/internal/shareable"
+)
+
+// availableFilename returns a filename that is valid as a new file or directory.
+func availableFilename(prefix, postfix string) (string, error) {
+	const datetimeFormat = "20060102030405"
+
+	now := time.Now()
+	name := fmt.Sprintf("%s%s%s", prefix, now.Format(datetimeFormat), postfix)
+	for i := 1; ; i++ {
+		if _, err := os.Stat(name); err != nil {
+			if os.IsNotExist(err) {
+				break
+			}
+			if !os.IsNotExist(err) {
+				return "", err
+			}
+		}
+		name = fmt.Sprintf("%s%s_%d%s", prefix, now.Format(datetimeFormat), i, postfix)
+	}
+	return name, nil
+}
+
+func takeScreenshot(screen *Image) error {
+	dump := func() (string, error) {
+		f, err := ioutil.TempFile("", "")
+		if err != nil {
+			return "", err
+		}
+		defer f.Close()
+
+		if err := png.Encode(f, screen); err != nil {
+			return "", err
+		}
+		return f.Name(), nil
+	}
+
+	name, err := dump()
+	if err != nil {
+		return err
+	}
+
+	newname, err := availableFilename("screenshot_", ".png")
+	if err != nil {
+		return err
+	}
+
+	if err := os.Rename(name, newname); err != nil {
+		return err
+	}
+
+	if _, err := fmt.Fprintf(os.Stderr, "Saved screenshot: %s\n", newname); err != nil {
+		return err
+	}
+	return nil
+}
+
+func dumpInternalImages() error {
+	dir, err := availableFilename("internalimages_", "")
+	if err != nil {
+		return err
+	}
+
+	if err := os.Mkdir(dir, 0755); err != nil {
+		return err
+	}
+
+	dump := func(img image.Image, index int) error {
+		filename := filepath.Join(dir, fmt.Sprintf("%d.png", index))
+		f, err := os.Create(filename)
+		if err != nil {
+			return err
+		}
+		defer f.Close()
+
+		if err := png.Encode(f, img); err != nil {
+			return err
+		}
+		return nil
+	}
+
+	for i, img := range shareable.Images() {
+		if err := dump(img, i); err != nil {
+			return err
+		}
+	}
+
+	if _, err := fmt.Fprintf(os.Stderr, "Dumped the internal images at: %s\n", dir); err != nil {
+		return err
+	}
+	return nil
+}
+
+type imageDumper struct {
+	f func(screen *Image) error
+
+	keyState map[Key]int
+
+	hasScreenshotKey bool
+	screenshotKey    Key
+	toTakeScreenshot bool
+
+	hasDumpInternalImagesKey bool
+	dumpInternalImagesKey    Key
+	toDumpInternalImages     bool
+}
+
+func (i *imageDumper) update(screen *Image) error {
+	const (
+		envScreenshotKey     = "EBITEN_SCREENSHOT_KEY"
+		envInternalImagesKey = "EBITEN_INTERNAL_IMAGES_KEY"
+	)
+
+	if err := i.f(screen); err != nil {
+		return err
+	}
+
+	// If keyState is nil, all values are not initialized.
+	if i.keyState == nil {
+		i.keyState = map[Key]int{}
+
+		if keyname := os.Getenv(envScreenshotKey); keyname != "" {
+			if key, ok := keyNameToKey(keyname); ok {
+				i.hasScreenshotKey = true
+				i.screenshotKey = key
+			}
+		}
+
+		if keyname := os.Getenv(envInternalImagesKey); keyname != "" {
+			if isDebug() {
+				if key, ok := keyNameToKey(keyname); ok {
+					i.hasDumpInternalImagesKey = true
+					i.dumpInternalImagesKey = key
+				}
+			} else {
+				fmt.Fprintf(os.Stderr, "%s is disabled. Specify a build tag 'ebitendebug' to enable it.\n", envInternalImagesKey)
+			}
+		}
+	}
+
+	keys := map[Key]struct{}{}
+	if i.hasScreenshotKey {
+		keys[i.screenshotKey] = struct{}{}
+	}
+	if i.hasDumpInternalImagesKey {
+		keys[i.dumpInternalImagesKey] = struct{}{}
+	}
+
+	for key := range keys {
+		if IsKeyPressed(key) {
+			i.keyState[key]++
+			if i.keyState[key] == 1 {
+				if i.hasScreenshotKey && key == i.screenshotKey {
+					i.toTakeScreenshot = true
+				}
+				if i.hasDumpInternalImagesKey && key == i.dumpInternalImagesKey {
+					i.toDumpInternalImages = true
+				}
+			}
+		} else {
+			i.keyState[key] = 0
+		}
+	}
+
+	if IsDrawingSkipped() {
+		return nil
+	}
+
+	if i.toTakeScreenshot {
+		i.toTakeScreenshot = false
+		if err := takeScreenshot(screen); err != nil {
+			return err
+		}
+	}
+
+	if i.toDumpInternalImages {
+		i.toDumpInternalImages = false
+		if err := dumpInternalImages(); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

imagedumper_notdesktop.go

@@ -0,0 +1,25 @@
+// Copyright 2018 The Ebiten Authors
+//
+// 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.
+
+// +build android js ios
+
+package ebiten
+
+type imageDumper struct {
+	f func(screen *Image) error
+}
+
+func (i *imageDumper) update(screen *Image) error {
+	return i.f(screen)
+}

run.go

@@ -15,17 +15,10 @@
 package ebiten
 
 import (
-	"fmt"
 	"image"
-	"io/ioutil"
-	"os"
-	"path/filepath"
 	"sync/atomic"
-	"time"
 
 	"github.com/hajimehoshi/ebiten/internal/clock"
-	"github.com/hajimehoshi/ebiten/internal/png"
-	"github.com/hajimehoshi/ebiten/internal/shareable"
 	"github.com/hajimehoshi/ebiten/internal/ui"
 )
 
@@ -107,171 +100,6 @@ func run(width, height int, scale float64, title string, g *graphicsContext, mai
 	return nil
 }
 
-type imageDumper struct {
-	f func(screen *Image) error
-
-	keyState map[Key]int
-
-	hasScreenshotKey bool
-	screenshotKey    Key
-	toTakeScreenshot bool
-
-	hasDumpInternalImagesKey bool
-	dumpInternalImagesKey    Key
-	toDumpInternalImages     bool
-}
-
-// availableFilename returns a filename that is valid as a new file or directory.
-func availableFilename(prefix, postfix string) (string, error) {
-	const datetimeFormat = "20060102030405"
-
-	now := time.Now()
-	name := fmt.Sprintf("%s%s%s", prefix, now.Format(datetimeFormat), postfix)
-	for i := 1; ; i++ {
-		if _, err := os.Stat(name); err != nil {
-			if os.IsNotExist(err) {
-				break
-			}
-			if !os.IsNotExist(err) {
-				return "", err
-			}
-		}
-		name = fmt.Sprintf("%s%s_%d%s", prefix, now.Format(datetimeFormat), i, postfix)
-	}
-	return name, nil
-}
-
-func (i *imageDumper) update(screen *Image) error {
-	const (
-		envScreenshotKey     = "EBITEN_SCREENSHOT_KEY"
-		envInternalImagesKey = "EBITEN_INTERNAL_IMAGES_KEY"
-	)
-
-	if err := i.f(screen); err != nil {
-		return err
-	}
-
-	// If keyState is nil, all values are not initialized.
-	if i.keyState == nil {
-		i.keyState = map[Key]int{}
-
-		if keyname := os.Getenv(envScreenshotKey); keyname != "" {
-			if key, ok := keyNameToKey(keyname); ok {
-				i.hasScreenshotKey = true
-				i.screenshotKey = key
-			}
-		}
-
-		if keyname := os.Getenv(envInternalImagesKey); keyname != "" {
-			if isDebug() {
-				if key, ok := keyNameToKey(keyname); ok {
-					i.hasDumpInternalImagesKey = true
-					i.dumpInternalImagesKey = key
-				}
-			} else {
-				fmt.Fprintf(os.Stderr, "%s is disabled. Specify a build tag 'ebitendebug' to enable it.\n", envInternalImagesKey)
-			}
-		}
-	}
-
-	keys := map[Key]struct{}{}
-	if i.hasScreenshotKey {
-		keys[i.screenshotKey] = struct{}{}
-	}
-	if i.hasDumpInternalImagesKey {
-		keys[i.dumpInternalImagesKey] = struct{}{}
-	}
-
-	for key := range keys {
-		if IsKeyPressed(key) {
-			i.keyState[key]++
-			if i.keyState[key] == 1 {
-				if i.hasScreenshotKey && key == i.screenshotKey {
-					i.toTakeScreenshot = true
-				}
-				if i.hasDumpInternalImagesKey && key == i.dumpInternalImagesKey {
-					i.toDumpInternalImages = true
-				}
-			}
-		} else {
-			i.keyState[key] = 0
-		}
-	}
-
-	if IsDrawingSkipped() {
-		return nil
-	}
-
-	if i.toTakeScreenshot {
-		dump := func() (string, error) {
-			f, err := ioutil.TempFile("", "")
-			if err != nil {
-				return "", err
-			}
-			defer f.Close()
-
-			if err := png.Encode(f, screen); err != nil {
-				return "", err
-			}
-			return f.Name(), nil
-		}
-
-		name, err := dump()
-		if err != nil {
-			return err
-		}
-
-		newname, err := availableFilename("screenshot_", ".png")
-		if err != nil {
-			return err
-		}
-
-		if err := os.Rename(name, newname); err != nil {
-			return err
-		}
-
-		i.toTakeScreenshot = false
-		fmt.Fprintf(os.Stderr, "Saved screenshot: %s\n", newname)
-	}
-
-	if i.toDumpInternalImages {
-		dir, err := availableFilename("internalimages_", "")
-		if err != nil {
-			return err
-		}
-
-		if err := os.Mkdir(dir, 0755); err != nil {
-			return err
-		}
-
-		dump := func(img image.Image, index int) error {
-			filename := filepath.Join(dir, fmt.Sprintf("%d.png", index))
-			f, err := os.Create(filename)
-			if err != nil {
-				return err
-			}
-			defer f.Close()
-
-			if err := png.Encode(f, img); err != nil {
-				return err
-			}
-			return nil
-		}
-
-		for i, img := range shareable.Images() {
-			if err := dump(img, i); err != nil {
-				return err
-			}
-		}
-
-		i.toDumpInternalImages = false
-
-		fmt.Fprintf(os.Stderr, "Dumped the internal images at: %s\n", dir)
-	}
-
-	return nil
-}
-
 // Run runs the game.
 // f is a function which is called at every frame.
 // The argument (*Image) is the render target that represents the screen.