audio: Add readerPlayerFactory / readerDriver

audio/audio.go

@@ -99,9 +99,16 @@ func NewContext(sampleRate int) *Context {
 		panic("audio: context is already created")
 	}
 
+	var np newPlayerImpler
+	if isReaderContextAvailable() {
+		np = newReaderPlayerFactory(sampleRate)
+	} else {
+		np = newWriterPlayerFactory(sampleRate)
+	}
+
 	c := &Context{
 		sampleRate: sampleRate,
-		np:         newWriterPlayerFactory(sampleRate),
+		np:         np,
 		players:    map[playerImpl]struct{}{},
 		inited:     make(chan struct{}),
 		semaphore:  make(chan struct{}, 1),

audio/readerplayer.go

@@ -0,0 +1,128 @@
+// Copyright 2021 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 audio
+
+import (
+	"io"
+	"runtime"
+	"sync"
+	"time"
+)
+
+// readerDriver represents a driver using io.ReadClosers.
+type readerDriver interface {
+	NewPlayer(io.Reader) readerDriverPlayer
+	io.Closer
+}
+
+type readerDriverPlayer interface {
+	Pause()
+	Play()
+	Volume() float64
+	SetVolume(volume float64)
+	io.Closer
+}
+
+type readerPlayerFactory struct {
+	driver readerDriver
+}
+
+func newReaderPlayerFactory(sampleRate int) *readerPlayerFactory {
+	return &readerPlayerFactory{
+		driver: newReaderDriverImpl(sampleRate),
+	}
+}
+
+type readerPlayer struct {
+	context *Context
+	player  readerDriverPlayer
+	src     io.Reader
+	playing bool
+	m       sync.Mutex
+}
+
+func (c *readerPlayerFactory) newPlayerImpl(context *Context, src io.Reader) (playerImpl, error) {
+	p := &readerPlayer{
+		context: context,
+		player:  c.driver.NewPlayer(src),
+		src:     src,
+	}
+	runtime.SetFinalizer(p, (*readerPlayer).Close)
+	return p, nil
+}
+
+func (p *readerPlayer) Play() {
+	p.m.Lock()
+	defer p.m.Unlock()
+
+	p.player.Play()
+	p.playing = true
+	p.context.addPlayer(p)
+}
+
+func (p *readerPlayer) Pause() {
+	p.m.Lock()
+	defer p.m.Unlock()
+
+	p.player.Pause()
+	p.playing = false
+}
+
+func (p *readerPlayer) IsPlaying() bool {
+	p.m.Lock()
+	defer p.m.Unlock()
+
+	return p.playing
+}
+
+func (p *readerPlayer) Volume() float64 {
+	p.m.Lock()
+	defer p.m.Unlock()
+
+	return p.player.Volume()
+}
+
+func (p *readerPlayer) SetVolume(volume float64) {
+	p.m.Lock()
+	defer p.m.Unlock()
+
+	p.player.SetVolume(volume)
+}
+
+func (p *readerPlayer) Close() error {
+	p.m.Lock()
+	defer p.m.Unlock()
+
+	runtime.SetFinalizer(p, nil)
+	p.context.removePlayer(p)
+	p.playing = false
+	return p.player.Close()
+}
+
+func (p *readerPlayer) Current() time.Duration {
+	panic("not implemented")
+}
+
+func (p *readerPlayer) Rewind() error {
+	panic("not implemented")
+}
+
+func (p *readerPlayer) Seek(offset time.Duration) error {
+	panic("not implemented")
+}
+
+func (p *readerPlayer) source() io.Reader {
+	return p.src
+}

audio/readerplayer_default.go

@@ -0,0 +1,30 @@
+// Copyright 2021 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 audio
+
+import (
+	"fmt"
+	"runtime"
+)
+
+func isReaderContextAvailable() bool {
+	return false
+}
+
+func newReaderDriverImpl(sampleRate int) readerDriver {
+	panic(fmt.Sprintf("audio: newReaderDriver is not available on this environment: GOOS=%s", runtime.GOOS))
+}

audio/readerplayer_js.go

@@ -0,0 +1,28 @@
+// Copyright 2021 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 audio
+
+import (
+	"syscall/js"
+)
+
+func isReaderContextAvailable() bool {
+	return js.Global().Get("go2cpp").Truthy()
+}
+
+func newReaderDriverImpl(sampleRate int) readerDriver {
+	// TODO: Implement this for go2cpp.
+	return nil
+}