Add ebitenmobile command

This works only for iOS so far. I'll implement Java version soon.

Updates #863

cmd/ebitenmobile/generate.go

@@ -12,11 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// +build ios
+//go:generate file2byteslice -package=main -input=gobind.go -output=gobind.src.go -var gobindsrc
 
-// TODO: Embed this header file to .framework by an original command.
-
-#import <UIKit/UIKit.h>
-
-@interface EbitenViewController : UIViewController
-@end
+package main

cmd/ebitenmobile/gobind.go

@@ -0,0 +1,199 @@
+// Copyright 2019 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 ebitenmobilegobind
+
+// gobind is a wrapper of the original gobind. This command adds extra files like a view controller.
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+
+	"golang.org/x/tools/go/packages"
+)
+
+var (
+	lang          = flag.String("lang", "", "")
+	outdir        = flag.String("outdir", "", "")
+	javaPkg       = flag.String("javapkg", "", "")
+	prefix        = flag.String("prefix", "", "")
+	bootclasspath = flag.String("bootclasspath", "", "")
+	classpath     = flag.String("classpath", "", "")
+	tags          = flag.String("tags", "", "")
+)
+
+var usage = `The Gobind tool generates Java language bindings for Go.
+
+For usage details, see doc.go.`
+
+func main() {
+	flag.Parse()
+	if err := run(); err != nil {
+		log.Fatal(err)
+	}
+}
+
+func run() error {
+	cmd := exec.Command("gobind-original", os.Args[1:]...)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	if err := cmd.Run(); err != nil {
+		return err
+	}
+
+	pkgs, err := packages.Load(nil, flag.Args()[0])
+	if err != nil {
+		return err
+	}
+	prefixLower := *prefix + pkgs[0].Name
+	prefixUpper := strings.Title(*prefix) + strings.Title(pkgs[0].Name)
+
+	writeFile := func(filename string, content string) error {
+		if err := ioutil.WriteFile(filepath.Join(*outdir, "src", "gobind", filename), []byte(content), 0644); err != nil {
+			return err
+		}
+		return nil
+	}
+	replacePrefixes := func(content string) string {
+		content = strings.ReplaceAll(content, "{{.PrefixUpper}}", prefixUpper)
+		content = strings.ReplaceAll(content, "{{.PrefixLower}}", prefixLower)
+		return content
+	}
+
+	// Add additional files.
+	langs := strings.Split(*lang, ",")
+	for _, lang := range langs {
+		switch lang {
+		case "objc":
+			// iOS
+			if err := writeFile(prefixLower+"ebitenviewcontroller_ios.m", replacePrefixes(objcM)); err != nil {
+				return err
+			}
+		case "java":
+			// Android
+			// TODO: Insert a Java file and let the original gobind compile it.
+		case "go":
+			// Do nothing.
+		default:
+			panic(fmt.Sprintf("unsupported language: %s", lang))
+		}
+	}
+
+	return nil
+}
+
+const objcM = `// Code generated by ebitenmobile. DO NOT EDIT.
+
+// +build ios
+
+#import <stdint.h>
+#import <UIKit/UIKit.h>
+#import <GLKit/GLkit.h>
+#import "Ebitenmobileview.objc.h"
+
+@interface {{.PrefixUpper}}EbitenViewController : UIViewController
+@end
+
+@implementation {{.PrefixUpper}}EbitenViewController {
+  GLKView* glkView_;
+}
+
+- (GLKView*)glkView {
+  if (!glkView_) {
+    glkView_ = [[GLKView alloc] init];
+    glkView_.multipleTouchEnabled = YES;
+  }
+  return glkView_;
+}
+
+- (void)viewDidLoad {
+  [super viewDidLoad];
+
+  self.glkView.delegate = (id<GLKViewDelegate>)(self);
+  [self.view addSubview: self.glkView];
+
+  EAGLContext *context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];
+  [self glkView].context = context;
+	
+  [EAGLContext setCurrentContext:context];
+	
+  CADisplayLink *displayLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(drawFrame)];
+  [displayLink addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
+}
+
+- (void)viewDidLayoutSubviews {
+  [super viewDidLayoutSubviews];
+  CGRect viewRect = [[self view] frame];
+
+  EbitenmobileviewLayout(viewRect.size.width, viewRect.size.height, (id<EbitenmobileviewViewRectSetter>)self);
+}
+
+- (void)setViewRect:(long)x y:(long)y width:(long)width height:(long)height {
+  CGRect glkViewRect = CGRectMake(x, y, width, height);
+  [[self glkView] setFrame:glkViewRect];
+}
+
+- (void)didReceiveMemoryWarning {
+  [super didReceiveMemoryWarning];
+  // Dispose of any resources that can be recreated.
+  // TODO: Notify this to Go world?
+}
+
+- (void)drawFrame{
+  [[self glkView] setNeedsDisplay];
+}
+
+- (void)glkView:(GLKView*)view drawInRect:(CGRect)rect {
+  NSError* err = nil;
+  EbitenmobileviewUpdate(&err);
+  if (err != nil) {
+    NSLog(@"Error: %@", err);
+  }
+}
+
+- (void)updateTouches:(NSSet*)touches {
+  for (UITouch* touch in touches) {
+    if (touch.view != [self glkView]) {
+      continue;
+    }
+    CGPoint location = [touch locationInView:touch.view];
+    EbitenmobileviewUpdateTouchesOnIOS(touch.phase, (uintptr_t)touch, location.x, location.y);
+  }
+}
+
+- (void)touchesBegan:(NSSet*)touches withEvent:(UIEvent*)event {
+  [self updateTouches:touches];
+}
+
+- (void)touchesMoved:(NSSet*)touches withEvent:(UIEvent*)event {
+  [self updateTouches:touches];
+}
+
+- (void)touchesEnded:(NSSet*)touches withEvent:(UIEvent*)event {
+  [self updateTouches:touches];
+}
+
+- (void)touchesCancelled:(NSSet*)touches withEvent:(UIEvent*)event {
+  [self updateTouches:touches];
+}
+
+@end
+`

cmd/ebitenmobile/gomobile.go

@@ -0,0 +1,110 @@
+// Copyright 2019 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.
+
+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+)
+
+const gomobileHash = "597adff16ade9d88626f8caea514bb189b8c74ee"
+
+func runGo(args ...string) error {
+	env := []string{
+		"GO111MODULE=on",
+	}
+
+	if buildX || buildN {
+		for _, e := range env {
+			fmt.Printf("%s ", e)
+		}
+		fmt.Print("go")
+		for _, arg := range args {
+			fmt.Printf(" %s", arg)
+		}
+		fmt.Println()
+	}
+
+	if buildN {
+		return nil
+	}
+
+	cmd := exec.Command("go", args...)
+	cmd.Env = append(os.Environ(), env...)
+	if out, err := cmd.CombinedOutput(); err != nil {
+		return fmt.Errorf("go %v failed: %v\n%v", args, string(out), err)
+	}
+	return nil
+}
+
+func prepareGomobileCommands() error {
+	tmp, err := ioutil.TempDir("", "ebitenmobile-")
+	if err != nil {
+		return err
+	}
+
+	newpath := filepath.Join(tmp, "bin")
+	if path := os.Getenv("PATH"); path != "" {
+		newpath += string(filepath.ListSeparator) + path
+	}
+	os.Setenv("PATH", newpath)
+
+	pwd, err := os.Getwd()
+	if err != nil {
+		return err
+	}
+
+	// cd
+	if buildX {
+		fmt.Printf("cd %s\n", tmp)
+	}
+	if err := os.Chdir(tmp); err != nil {
+		return err
+	}
+	defer func() {
+		os.Chdir(pwd)
+	}()
+
+	if err := runGo("mod", "init", "ebitenmobiletemporary"); err != nil {
+		return err
+	}
+	if err := runGo("get", "golang.org/x/mobile@"+gomobileHash); err != nil {
+		return err
+	}
+	if err := runGo("build", "-o", filepath.Join("bin", "gomobile"), "golang.org/x/mobile/cmd/gomobile"); err != nil {
+		return err
+	}
+	if err := runGo("build", "-o", filepath.Join("bin", "gobind-original"), "golang.org/x/mobile/cmd/gobind"); err != nil {
+		return err
+	}
+
+	if err := os.Mkdir("src", 0755); err != nil {
+		return err
+	}
+	if err := ioutil.WriteFile(filepath.Join("src", "gobind.go"), gobindsrc, 0644); err != nil {
+		return err
+	}
+
+	if err := runGo("build", "-o", filepath.Join("bin", "gobind"), "-tags", "ebitenmobilegobind", filepath.Join("src", "gobind.go")); err != nil {
+		return err
+	}
+
+	// TODO: Create a gobind wrapper
+
+	return nil
+}

cmd/ebitenmobile/main.go

@@ -0,0 +1,222 @@
+// Copyright 2019 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.
+
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"text/template"
+
+	"golang.org/x/tools/go/packages"
+)
+
+const (
+	ebitenmobileCommand = "ebitenmobile"
+)
+
+func init() {
+	flag.Usage = func() {
+		// This message is copied from `gomobile bind -h`
+		fmt.Fprintf(os.Stderr, "%s bind [-target android|ios] [-bootclasspath <path>] [-classpath <path>] [-o output] [build flags] [package]", ebitenmobileCommand)
+		os.Exit(2)
+	}
+	flag.Parse()
+}
+
+func goEnv(name string) string {
+	if val := os.Getenv(name); val != "" {
+		return val
+	}
+	val, err := exec.Command("go", "env", name).Output()
+	if err != nil {
+		panic(err)
+	}
+	return strings.TrimSpace(string(val))
+}
+
+const (
+	// Copied from gomobile.
+	minAndroidAPI = 15
+)
+
+var (
+	buildA          bool   // -a
+	buildI          bool   // -i
+	buildN          bool   // -n
+	buildV          bool   // -v
+	buildX          bool   // -x
+	buildO          string // -o
+	buildGcflags    string // -gcflags
+	buildLdflags    string // -ldflags
+	buildTarget     string // -target
+	buildWork       bool   // -work
+	buildBundleID   string // -bundleid
+	buildIOSVersion string // -iosversion
+	buildAndroidAPI int    // -androidapi
+	buildTags       string // -tags
+
+	bindPrefix        string // -prefix
+	bindJavaPkg       string // -javapkg
+	bindClasspath     string // -classpath
+	bindBootClasspath string // -bootclasspath
+)
+
+func main() {
+	args := flag.Args()
+	if len(args) < 1 {
+		flag.Usage()
+	}
+
+	var flagset flag.FlagSet
+	flagset.StringVar(&buildO, "o", "", "")
+	flagset.StringVar(&buildGcflags, "gcflags", "", "")
+	flagset.StringVar(&buildLdflags, "ldflags", "", "")
+	flagset.StringVar(&buildTarget, "target", "android", "")
+	flagset.StringVar(&buildBundleID, "bundleid", "", "")
+	flagset.StringVar(&buildIOSVersion, "iosversion", "7.0", "")
+	flagset.StringVar(&buildTags, "tags", "", "")
+	flagset.IntVar(&buildAndroidAPI, "androidapi", minAndroidAPI, "")
+	flagset.BoolVar(&buildA, "a", false, "")
+	flagset.BoolVar(&buildI, "i", false, "")
+	flagset.BoolVar(&buildN, "n", false, "")
+	flagset.BoolVar(&buildV, "v", false, "")
+	flagset.BoolVar(&buildX, "x", false, "")
+	flagset.BoolVar(&buildWork, "work", false, "")
+	flagset.StringVar(&bindJavaPkg, "javapkg", "", "")
+	flagset.StringVar(&bindPrefix, "prefix", "", "")
+	flagset.StringVar(&bindClasspath, "classpath", "", "")
+	flagset.StringVar(&bindBootClasspath, "bootclasspath", "", "")
+
+	flagset.Parse(args[1:])
+
+	if err := prepareGomobileCommands(); err != nil {
+		log.Fatal(err)
+	}
+
+	switch args[0] {
+	case "bind":
+		if err := doBind(args, &flagset); err != nil {
+			log.Fatal(err)
+		}
+	default:
+		flag.Usage()
+	}
+}
+
+func doBind(args []string, flagset *flag.FlagSet) error {
+	pkgs, err := packages.Load(nil, flagset.Args()[0])
+	if err != nil {
+		return err
+	}
+	prefixLower := bindPrefix + pkgs[0].Name
+	prefixUpper := strings.Title(bindPrefix) + strings.Title(pkgs[0].Name)
+
+	args = append(args, "github.com/hajimehoshi/ebiten/mobile/ebitenmobileview")
+
+	if buildO == "" {
+		fmt.Fprintln(os.Stderr, "-o must be specified.")
+		os.Exit(2)
+		return nil
+	}
+
+	if buildN {
+		fmt.Print("gomobile")
+		for _, arg := range args {
+			fmt.Print(" ", arg)
+		}
+		fmt.Println()
+		return nil
+	}
+
+	cmd := exec.Command("gomobile", args...)
+	cmd.Env = append(cmd.Env, os.Environ()...)
+	cmd.Env = append(cmd.Env, "GO111MODULE=off")
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	if err := cmd.Run(); err != nil {
+		os.Exit(err.(*exec.ExitError).ExitCode())
+		return nil
+	}
+
+	replacePrefixes := func(content string) string {
+		content = strings.ReplaceAll(content, "{{.PrefixUpper}}", prefixUpper)
+		content = strings.ReplaceAll(content, "{{.PrefixLower}}", prefixLower)
+		return content
+	}
+
+	switch buildTarget {
+	case "android":
+		// Do nothing.
+	case "ios":
+		dir := filepath.Join(buildO, "Versions", "A")
+
+		if err := ioutil.WriteFile(filepath.Join(dir, "Headers", prefixUpper+"EbitenViewController.h"), []byte(replacePrefixes(objcH)), 0644); err != nil {
+			return err
+		}
+		// TODO: Remove 'Ebitenmobileview.objc.h' here. Now it is hard since there is a header file importing
+		// that header file.
+
+		fs, err := ioutil.ReadDir(filepath.Join(dir, "Headers"))
+		if err != nil {
+			return err
+		}
+		var headerFiles []string
+		for _, f := range fs {
+			if strings.HasSuffix(f.Name(), ".h") {
+				headerFiles = append(headerFiles, f.Name())
+			}
+		}
+
+		w, err := os.OpenFile(filepath.Join(dir, "Modules", "module.modulemap"), os.O_WRONLY, 0644)
+		if err != nil {
+			return err
+		}
+		defer w.Close()
+		var mmVals = struct {
+			Module  string
+			Headers []string
+		}{
+			Module:  prefixUpper,
+			Headers: headerFiles,
+		}
+		if err := iosModuleMapTmpl.Execute(w, mmVals); err != nil {
+			return err
+		}
+
+		// TODO: Remove Ebitenmobileview.objc.h?
+	}
+
+	return nil
+}
+
+const objcH = `// Code generated by ebitenmobile. DO NOT EDIT.
+
+#import <UIKit/UIKit.h>
+
+@interface {{.PrefixUpper}}EbitenViewController : UIViewController
+@end
+`
+
+var iosModuleMapTmpl = template.Must(template.New("iosmmap").Parse(`framework module "{{.Module}}" {
+{{range .Headers}}    header "{{.}}"
+{{end}}
+    export *
+}`))

go.mod

@@ -16,5 +16,6 @@ require (
 	golang.org/x/image v0.0.0-20190703141733-d6a02ce849c9
 	golang.org/x/mobile v0.0.0-20190711165009-e47acb2ca7f9
 	golang.org/x/sys v0.0.0-20190712062909-fae7ac547cb7
+	golang.org/x/tools v0.0.0-20190816200558-6889da9d5479
 	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
 )

go.sum

@@ -24,6 +24,7 @@ github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/pkg/browser v0.0.0-20180916011732-0a3d74bf9ce4/go.mod h1:4OwLy04Bl9Ef3GJJCoec+30X3LQs/0/m4HFRt/2LUSA=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/exp v0.0.0-20190306152737-a1d7652674e8 h1:idBdZTd9UioThJp8KpM/rTSinK/ChZFBE43/WtIy8zg=
 golang.org/x/exp v0.0.0-20190306152737-a1d7652674e8/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/image v0.0.0-20190227222117-0694c2d4d067 h1:KYGJGHOQy8oSi1fDlSpcZF0+juKwk/hEMv5SiwHogR0=
@@ -34,11 +35,17 @@ golang.org/x/mobile v0.0.0-20190415191353-3e0bab5405d6 h1:vyLBGJPIl9ZYbcQFM2USFm
 golang.org/x/mobile v0.0.0-20190415191353-3e0bab5405d6/go.mod h1:E/iHnbuqvinMTCcRqshq8CkpyQDoeVncDDYHnLhea+o=
 golang.org/x/mobile v0.0.0-20190711165009-e47acb2ca7f9 h1:m1yPOfTCyrqD6atBVpXfysvXc1bhSMdIxBu0JQAM7mQ=
 golang.org/x/mobile v0.0.0-20190711165009-e47acb2ca7f9/go.mod h1:E/iHnbuqvinMTCcRqshq8CkpyQDoeVncDDYHnLhea+o=
+golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190312061237-fead79001313/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190429190828-d89cdac9e872 h1:cGjJzUd8RgBw428LXP65YXni0aiGNA4Bl+ls8SmLOm8=
 golang.org/x/sys v0.0.0-20190429190828-d89cdac9e872/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190712062909-fae7ac547cb7 h1:LepdCS8Gf/MVejFIt8lsiexZATdoGVyp5bcyS+rYoUI=
 golang.org/x/sys v0.0.0-20190712062909-fae7ac547cb7/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/tools v0.0.0-20190816200558-6889da9d5479 h1:lfN2PY/jymfnxkNHlbBF5DwPsUvhqUnrdgfK01iH2s0=
+golang.org/x/tools v0.0.0-20190816200558-6889da9d5479/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=

mobile/ebitenmobileview/c.go

@@ -1,113 +0,0 @@
-// Copyright 2019 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.
-
-package ebitenmobileview
-
-// #cgo ios LDFLAGS: -framework UIKit -framework GLKit -framework QuartzCore -framework OpenGLES
-//
-// #include <stdint.h>
-import "C"
-
-import (
-	"math"
-	"runtime"
-	"sync"
-
-	"github.com/hajimehoshi/ebiten"
-)
-
-var theState state
-
-// game is not exported since gomobile complains.
-// TODO: Report this error.
-type game interface {
-	Update(*ebiten.Image) error
-	Layout(viewWidth, viewHeight int) (screenWidth, screenHeight int)
-}
-
-type state struct {
-	game game
-
-	running bool
-
-	// m is a mutex required for each function.
-	// For example, on Android, Update can be called from a different thread:
-	// https://developer.android.com/reference/android/opengl/GLSurfaceView.Renderer
-	m sync.Mutex
-}
-
-func SetGame(game game) {
-	theState.m.Lock()
-	defer theState.m.Unlock()
-
-	theState.game = game
-}
-
-//export ebitenLayout
-func ebitenLayout(viewWidth, viewHeight C.int, x, y, width, height *C.int) {
-	theState.m.Lock()
-	defer theState.m.Unlock()
-
-	if theState.game == nil {
-		panic("ebitenmobileview: SetGame must be called before ebitenLayout")
-	}
-
-	w, h := theState.game.Layout(int(viewWidth), int(viewHeight))
-	scaleX := float64(viewWidth) / float64(w)
-	scaleY := float64(viewHeight) / float64(h)
-	scale := math.Min(scaleX, scaleY)
-
-	*width = C.int(math.Ceil(float64(w) * scale))
-	*height = C.int(math.Ceil(float64(h) * scale))
-	*x = (viewWidth - *width) / 2
-	*y = (viewHeight - *height) / 2
-
-	if !theState.running {
-		start(theState.game.Update, w, h, scale)
-		theState.running = true
-	}
-	// TODO: call SetScreenSize
-}
-
-//export ebitenUpdate
-func ebitenUpdate() *C.char {
-	runtime.LockOSThread()
-	defer runtime.UnlockOSThread()
-
-	theState.m.Lock()
-	defer theState.m.Unlock()
-
-	if err := update(); err != nil {
-		// TODO: When to free cstr?
-		cstr := C.CString(err.Error())
-		return cstr
-	}
-	return nil
-}
-
-//export ebitenUpdateTouchesOnIOS
-func ebitenUpdateTouchesOnIOS(phase C.int, ptr C.uintptr_t, x, y C.int) {
-	theState.m.Lock()
-	defer theState.m.Unlock()
-
-	updateTouchesOnIOSImpl(int(phase), int64(ptr), int(x), int(y))
-}
-
-//export ebitenUpdateTouchesOnAndroid
-func ebitenUpdateTouchesOnAndroid(action C.int, id C.int, x, y C.int) {
-	theState.m.Lock()
-	defer theState.m.Unlock()
-
-	updateTouchesOnAndroid(int(action), int(id), int(x), int(y))
-}

mobile/ebitenmobileview/ebitenviewcontroller_ios.m

@@ -1,105 +0,0 @@
-// Copyright 2019 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 ios
-
-#import <UIKit/UIKit.h>
-#import <GLKit/GLkit.h>
-
-#import "ebitenviewcontroller_ios.h"
-
-#include "_cgo_export.h"
-
-@implementation EbitenViewController {
-  GLKView* glkView_;
-}
-
-- (GLKView*)glkView {
-  if (!glkView_) {
-    glkView_ = [[GLKView alloc] init];
-    glkView_.multipleTouchEnabled = YES;
-  }
-  return glkView_;
-}
-
-- (void)viewDidLoad {
-  [super viewDidLoad];
-
-  self.glkView.delegate = (id<GLKViewDelegate>)(self);
-  [self.view addSubview: self.glkView];
-
-  EAGLContext *context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];
-  [self glkView].context = context;
-	
-  [EAGLContext setCurrentContext:context];
-	
-  CADisplayLink *displayLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(drawFrame)];
-  [displayLink addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
-}
-
-- (void)viewDidLayoutSubviews {
-  [super viewDidLayoutSubviews];
-  CGRect viewRect = [[self view] frame];
-
-  int x, y, width, height;
-  ebitenLayout(viewRect.size.width, viewRect.size.height, &x, &y, &width, &height);
-
-  CGRect glkViewRect = CGRectMake(x, y, width, height);
-  [[self glkView] setFrame:glkViewRect];
-}
-
-- (void)didReceiveMemoryWarning {
-  [super didReceiveMemoryWarning];
-  // Dispose of any resources that can be recreated.
-  // TODO: Notify this to Go world?
-}
-
-- (void)drawFrame{
-  [[self glkView] setNeedsDisplay];
-}
-
-- (void)glkView:(GLKView*)view drawInRect:(CGRect)rect {
-  const char* err = ebitenUpdate();
-  if (err != nil) {
-    NSLog(@"Error: %s", err);
-  }
-}
-
-- (void)updateTouches:(NSSet*)touches {
-  for (UITouch* touch in touches) {
-    if (touch.view != [self glkView]) {
-      continue;
-    }
-    CGPoint location = [touch locationInView:touch.view];
-    ebitenUpdateTouchesOnIOS(touch.phase, (uintptr_t)touch, location.x, location.y);
-  }
-}
-
-- (void)touchesBegan:(NSSet*)touches withEvent:(UIEvent*)event {
-  [self updateTouches:touches];
-}
-
-- (void)touchesMoved:(NSSet*)touches withEvent:(UIEvent*)event {
-  [self updateTouches:touches];
-}
-
-- (void)touchesEnded:(NSSet*)touches withEvent:(UIEvent*)event {
-  [self updateTouches:touches];
-}
-
-- (void)touchesCancelled:(NSSet*)touches withEvent:(UIEvent*)event {
-  [self updateTouches:touches];
-}
-
-@end

mobile/ebitenmobileview/game.go

@@ -0,0 +1,55 @@
+// Copyright 2019 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.
+
+package ebitenmobileview
+
+// #cgo ios LDFLAGS: -framework UIKit -framework GLKit -framework QuartzCore -framework OpenGLES
+//
+// #include <stdint.h>
+import "C"
+
+import (
+	"math"
+	"runtime"
+	"sync"
+
+	"github.com/hajimehoshi/ebiten"
+)
+
+var theState state
+
+// game is not exported since gomobile complains.
+// TODO: Report this error.
+type game interface {
+	Update(*ebiten.Image) error
+	Layout(viewWidth, viewHeight int) (screenWidth, screenHeight int)
+}
+
+type state struct {
+	game game
+
+	running bool
+
+	// m is a mutex required for each function.
+	// For example, on Android, Update can be called from a different thread:
+	// https://developer.android.com/reference/android/opengl/GLSurfaceView.Renderer
+	m sync.Mutex
+}
+
+func SetGame(game game) {
+	theState.m.Lock()
+	defer theState.m.Unlock()
+
+	theState.game = game
+}