Add jsutil package for new API of Go 1.13

Audio part still cannot be compiled due to Oto.

Fixes #878

audio/mp3/decode_js.go

@@ -26,6 +26,7 @@ import (
 	"time"
 
 	"github.com/hajimehoshi/ebiten/audio"
+	"github.com/hajimehoshi/ebiten/internal/jsutil"
 )
 
 // TODO: This just uses decodeAudioData, that can treat audio files other than MP3.
@@ -174,9 +175,9 @@ func init() {
 
 func float32ArrayToSlice(arr js.Value) []float32 {
 	f := make([]float32, arr.Length())
-	a := js.TypedArrayOf(f)
+	a, free := jsutil.SliceToTypedArray(f)
 	a.Call("set", arr)
-	a.Release()
+	free()
 	return f
 }
 
@@ -195,7 +196,7 @@ func decode(context *audio.Context, buf []byte, try int) (*Stream, error) {
 	// TODO: 1 is a correct second argument?
 	oc := offlineAudioContextClass.New(2, 1, context.SampleRate())
 
-	u8 := js.TypedArrayOf(buf)
+	u8, free := jsutil.SliceToTypedArray(buf)
 	a := u8.Get("buffer").Call("slice", u8.Get("byteOffset"), u8.Get("byteOffset").Int()+u8.Get("byteLength").Int())
 
 	succeeded := js.FuncOf(func(this js.Value, args []js.Value) interface{} {
@@ -229,7 +230,7 @@ func decode(context *audio.Context, buf []byte, try int) (*Stream, error) {
 	defer failed.Release()
 
 	oc.Call("decodeAudioData", a, succeeded, failed)
-	u8.Release()
+	free()
 
 	timeout := time.Duration(math.Pow(2, float64(try))) * time.Second
 	t := time.NewTimer(timeout)

audio/vorbis/internal/stb/decode_js.go

@@ -18,6 +18,8 @@ import (
 	"fmt"
 	"io"
 	"syscall/js"
+
+	"github.com/hajimehoshi/ebiten/internal/jsutil"
 )
 
 var flatten = js.Global().Get("window").Call("eval", `(function(arr) {
@@ -117,9 +119,9 @@ func DecodeVorbis(buf []byte) (*Samples, int, int, error) {
 		}
 
 		s := make([]float32, flattened.Length())
-		arr := js.TypedArrayOf(s)
+		arr, free := jsutil.SliceToTypedArray(s)
 		arr.Call("set", flattened)
-		arr.Release()
+		free()
 
 		samples.samples = append(samples.samples, s)
 		samples.lengthInSamples += int64(len(s)) / int64(samples.channels)
@@ -127,9 +129,9 @@ func DecodeVorbis(buf []byte) (*Samples, int, int, error) {
 	})
 	defer f.Release()
 
-	arr := js.TypedArrayOf(buf)
+	arr, free := jsutil.SliceToTypedArray(buf)
 	js.Global().Get("stbvorbis").Call("decode", arr, f)
-	arr.Release()
+	free()
 
 	if err := <-ch; err != nil {
 		return nil, 0, 0, err

ebitenutil/file_js.go

@@ -21,6 +21,8 @@ import (
 	"errors"
 	"fmt"
 	"syscall/js"
+
+	"github.com/hajimehoshi/ebiten/internal/jsutil"
 )
 
 type file struct {
@@ -63,11 +65,6 @@ func OpenFile(path string) (ReadSeekCloser, error) {
 		return nil, err
 	}
 
-	uint8contentWrapper := js.Global().Get("Uint8Array").New(content)
-	data := make([]byte, uint8contentWrapper.Get("byteLength").Int())
-	arr := js.TypedArrayOf(data)
-	arr.Call("set", uint8contentWrapper)
-	arr.Release()
-	f := &file{bytes.NewReader(data)}
+	f := &file{bytes.NewReader(jsutil.ArrayBufferToSlice(content))}
 	return f, nil
 }

internal/graphicsdriver/opengl/context_js.go

@@ -22,6 +22,7 @@ import (
 	"syscall/js"
 
 	"github.com/hajimehoshi/ebiten/internal/graphics"
+	"github.com/hajimehoshi/ebiten/internal/jsutil"
 	"github.com/hajimehoshi/ebiten/internal/web"
 )
 
@@ -189,11 +190,10 @@ func (c *context) framebufferPixels(f *framebuffer, width, height int) ([]byte,
 
 	c.bindFramebuffer(f.native)
 
-	pixels := make([]byte, 4*width*height)
-	p := js.TypedArrayOf(pixels)
+	p := js.Global().Get("Uint8Array").New(4 * width * height)
 	gl.Call("readPixels", 0, 0, width, height, rgba, unsignedByte, p)
-	p.Release()
-	return pixels, nil
+
+	return jsutil.Uint8ArrayToSlice(p), nil
 }
 
 func (c *context) bindTextureImpl(t textureNative) {
@@ -227,9 +227,9 @@ func (c *context) texSubImage2D(t textureNative, pixels []byte, x, y, width, hei
 	// void texSubImage2D(GLenum target, GLint level, GLint xoffset, GLint yoffset,
 	//                    GLsizei width, GLsizei height,
 	//                    GLenum format, GLenum type, ArrayBufferView? pixels);
-	p := js.TypedArrayOf(pixels)
+	p, free := jsutil.SliceToTypedArray(pixels)
 	gl.Call("texSubImage2D", texture2d, 0, x, y, width, height, rgba, unsignedByte, p)
-	p.Release()
+	free()
 }
 
 func (c *context) newFramebuffer(t textureNative) (framebufferNative, error) {
@@ -367,9 +367,9 @@ func (c *context) uniformFloats(p program, location string, v []float32) {
 	case 4:
 		gl.Call("uniform4f", js.Value(l), v[0], v[1], v[2], v[3])
 	case 16:
-		arr := js.TypedArrayOf(v)
+		arr, free := jsutil.SliceToTypedArray(v)
 		gl.Call("uniformMatrix4fv", js.Value(l), false, arr)
-		arr.Release()
+		free()
 	default:
 		panic(fmt.Sprintf("opengl: invalid uniform floats num: %d", len(v)))
 	}
@@ -420,17 +420,17 @@ func (c *context) bindBuffer(bufferType bufferType, b buffer) {
 func (c *context) arrayBufferSubData(data []float32) {
 	c.ensureGL()
 	gl := c.gl
-	arr := js.TypedArrayOf(data)
+	arr, free := jsutil.SliceToTypedArray(data)
 	gl.Call("bufferSubData", int(arrayBuffer), 0, arr)
-	arr.Release()
+	free()
 }
 
 func (c *context) elementArrayBufferSubData(data []uint16) {
 	c.ensureGL()
 	gl := c.gl
-	arr := js.TypedArrayOf(data)
+	arr, free := jsutil.SliceToTypedArray(data)
 	gl.Call("bufferSubData", int(elementArrayBuffer), 0, arr)
-	arr.Release()
+	free()
 }
 
 func (c *context) deleteBuffer(b buffer) {

internal/jsutil/go112_js.go

@@ -0,0 +1,44 @@
+// 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 !go1.13 !wasm
+
+package jsutil
+
+import (
+	"syscall/js"
+)
+
+func Uint8ArrayToSlice(value js.Value) []byte {
+	// Note that TypedArrayOf cannot work correcly on Wasm.
+	// See https://github.com/golang/go/issues/31980
+
+	s := make([]byte, value.Get("byteLength").Int())
+	a := js.TypedArrayOf(s)
+	a.Call("set", value)
+	a.Release()
+	return s
+}
+
+func ArrayBufferToSlice(value js.Value) []byte {
+	return Uint8ArrayToSlice(js.Global().Get("Uint8Array").New(value))
+}
+
+func SliceToTypedArray(s interface{}) (js.Value, func()) {
+	// Note that TypedArrayOf cannot work correcly on Wasm.
+	// See https://github.com/golang/go/issues/31980
+
+	a := js.TypedArrayOf(s)
+	return a.Value, func() { a.Release() }
+}

internal/jsutil/go113_js.go

@@ -0,0 +1,141 @@
+// 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 go1.13
+
+package jsutil
+
+import (
+	"fmt"
+	"reflect"
+	"runtime"
+	"syscall/js"
+	"unsafe"
+)
+
+func Uint8ArrayToSlice(value js.Value) []byte {
+	s := make([]byte, value.Get("byteLength").Int())
+	js.CopyBytesToGo(s, value)
+	return s
+}
+
+func ArrayBufferToSlice(value js.Value) []byte {
+	return Uint8ArrayToSlice(js.Global().Get("Uint8Array").New(value))
+}
+
+func sliceToByteSlice(s interface{}) []byte {
+	switch s := s.(type) {
+	case []int8:
+		h := (*reflect.SliceHeader)(unsafe.Pointer(&s))
+		return *(*[]byte)(unsafe.Pointer(h))
+	case []int16:
+		h := (*reflect.SliceHeader)(unsafe.Pointer(&s))
+		h.Len *= 2
+		h.Cap *= 2
+		return *(*[]byte)(unsafe.Pointer(h))
+	case []int32:
+		h := (*reflect.SliceHeader)(unsafe.Pointer(&s))
+		h.Len *= 4
+		h.Cap *= 4
+		return *(*[]byte)(unsafe.Pointer(h))
+	case []int64:
+		h := (*reflect.SliceHeader)(unsafe.Pointer(&s))
+		h.Len *= 8
+		h.Cap *= 8
+		return *(*[]byte)(unsafe.Pointer(h))
+	case []uint8:
+		return s
+	case []uint16:
+		h := (*reflect.SliceHeader)(unsafe.Pointer(&s))
+		h.Len *= 2
+		h.Cap *= 2
+		return *(*[]byte)(unsafe.Pointer(h))
+	case []uint32:
+		h := (*reflect.SliceHeader)(unsafe.Pointer(&s))
+		h.Len *= 4
+		h.Cap *= 4
+		return *(*[]byte)(unsafe.Pointer(h))
+	case []uint64:
+		h := (*reflect.SliceHeader)(unsafe.Pointer(&s))
+		h.Len *= 8
+		h.Cap *= 8
+		return *(*[]byte)(unsafe.Pointer(h))
+	case []float32:
+		h := (*reflect.SliceHeader)(unsafe.Pointer(&s))
+		h.Len *= 4
+		h.Cap *= 4
+		return *(*[]byte)(unsafe.Pointer(h))
+	case []float64:
+		h := (*reflect.SliceHeader)(unsafe.Pointer(&s))
+		h.Len *= 8
+		h.Cap *= 8
+		return *(*[]byte)(unsafe.Pointer(h))
+	default:
+		panic(fmt.Sprintf("jsutil: unexpected value at sliceToBytesSlice: %T", s))
+	}
+}
+
+func SliceToTypedArray(s interface{}) (js.Value, func()) {
+	switch s := s.(type) {
+	case []int8:
+		a := js.Global().Get("Uint8Array").New(len(s))
+		js.CopyBytesToJS(a, sliceToByteSlice(s))
+		runtime.KeepAlive(s)
+		buf := a.Get("buffer")
+		return js.Global().Get("Int8Array").New(buf, a.Get("byteOffset"), a.Get("byteLength")), func() {}
+	case []int16:
+		a := js.Global().Get("Uint8Array").New(len(s) * 2)
+		js.CopyBytesToJS(a, sliceToByteSlice(s))
+		runtime.KeepAlive(s)
+		buf := a.Get("buffer")
+		return js.Global().Get("Int16Array").New(buf, a.Get("byteOffset"), a.Get("byteLength").Int()/2), func() {}
+	case []int32:
+		a := js.Global().Get("Uint8Array").New(len(s) * 4)
+		js.CopyBytesToJS(a, sliceToByteSlice(s))
+		runtime.KeepAlive(s)
+		buf := a.Get("buffer")
+		return js.Global().Get("Int32Array").New(buf, a.Get("byteOffset"), a.Get("byteLength").Int()/4), func() {}
+	case []uint8:
+		a := js.Global().Get("Uint8Array").New(len(s))
+		js.CopyBytesToJS(a, s)
+		runtime.KeepAlive(s)
+		return a, func() {}
+	case []uint16:
+		a := js.Global().Get("Uint8Array").New(len(s) * 2)
+		js.CopyBytesToJS(a, sliceToByteSlice(s))
+		runtime.KeepAlive(s)
+		buf := a.Get("buffer")
+		return js.Global().Get("Uint16Array").New(buf, a.Get("byteOffset"), a.Get("byteLength").Int()/2), func() {}
+	case []uint32:
+		a := js.Global().Get("Uint8Array").New(len(s) * 4)
+		js.CopyBytesToJS(a, sliceToByteSlice(s))
+		runtime.KeepAlive(s)
+		buf := a.Get("buffer")
+		return js.Global().Get("Uint32Array").New(buf, a.Get("byteOffset"), a.Get("byteLength").Int()/4), func() {}
+	case []float32:
+		a := js.Global().Get("Uint8Array").New(len(s) * 4)
+		js.CopyBytesToJS(a, sliceToByteSlice(s))
+		runtime.KeepAlive(s)
+		buf := a.Get("buffer")
+		return js.Global().Get("Float32Array").New(buf, a.Get("byteOffset"), a.Get("byteLength").Int()/4), func() {}
+	case []float64:
+		a := js.Global().Get("Uint8Array").New(len(s) * 8)
+		js.CopyBytesToJS(a, sliceToByteSlice(s))
+		runtime.KeepAlive(s)
+		buf := a.Get("buffer")
+		return js.Global().Get("Float64Array").New(buf, a.Get("byteOffset"), a.Get("byteLength").Int()/8), func() {}
+	default:
+		panic(fmt.Sprintf("jsutil: unexpected value at SliceToTypedArray: %T", s))
+	}
+}

internal/jsutil/jsutil_test.go

@@ -0,0 +1,94 @@
+// 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 js
+
+package jsutil_test
+
+import (
+	"syscall/js"
+	"testing"
+
+	. "github.com/hajimehoshi/ebiten/internal/jsutil"
+)
+
+func jsArray(values []float64) js.Value {
+	a := js.Global().Get("Array").New()
+	for _, v := range values {
+		a.Call("push", v)
+	}
+	return a
+}
+
+func TestArrayBufferToSlice(t *testing.T) {
+	// TODO
+}
+
+func TestSliceToTypedArray(t *testing.T) {
+	tests := []struct {
+		in  interface{}
+		out js.Value
+	}{
+		{
+			in:  []int8{1, 2, 3},
+			out: js.Global().Get("Int8Array").Call("of", 1, 2, 3),
+		},
+		{
+			in:  []int16{1, 2, 3},
+			out: js.Global().Get("Int16Array").Call("of", 1, 2, 3),
+		},
+		{
+			in:  []int32{1, 2, 3},
+			out: js.Global().Get("Int32Array").Call("of", 1, 2, 3),
+		},
+		{
+			in:  []uint8{1, 2, 3},
+			out: js.Global().Get("Uint8Array").Call("of", 1, 2, 3),
+		},
+		{
+			in:  []uint16{1, 2, 3},
+			out: js.Global().Get("Uint16Array").Call("of", 1, 2, 3),
+		},
+		{
+			in:  []uint32{1, 2, 3},
+			out: js.Global().Get("Uint32Array").Call("of", 1, 2, 3),
+		},
+		{
+			in:  []float32{1, 2, 3},
+			out: js.Global().Get("Float32Array").Call("of", 1, 2, 3),
+		},
+		{
+			in:  []float64{1, 2, 3},
+			out: js.Global().Get("Float64Array").Call("of", 1, 2, 3),
+		},
+	}
+	for _, test := range tests {
+		got, free := SliceToTypedArray(test.in)
+		defer free()
+		want := test.out
+		if got.Get("constructor") != want.Get("constructor") {
+			t.Errorf("class: got: %s, want: %s", got.Get("constructor").Get("name"), want.Get("constructor").Get("name"))
+		}
+		if got.Length() != want.Length() {
+			t.Errorf("length: got: %d, want: %d", got.Length(), want.Length())
+		}
+		for i := 0; i < got.Length(); i++ {
+			gotv := got.Index(i).Float()
+			wantv := want.Index(i).Float()
+			if gotv != wantv {
+				t.Errorf("[%d]: got: %v, want: %v", i, gotv, wantv)
+			}
+		}
+	}
+}