ebiten/examples/audio/main.go
2021-05-04 02:02:17 +09:00

457 lines
9.9 KiB
Go

// Copyright 2016 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.
// +build example
// This is an example to implement an audio player.
// See examples/wav for a simpler example to play a sound file.
package main
import (
"bytes"
"fmt"
"image"
"image/color"
_ "image/png"
"io"
"io/ioutil"
"log"
"time"
"github.com/hajimehoshi/ebiten/v2"
"github.com/hajimehoshi/ebiten/v2/audio"
"github.com/hajimehoshi/ebiten/v2/audio/mp3"
"github.com/hajimehoshi/ebiten/v2/audio/vorbis"
"github.com/hajimehoshi/ebiten/v2/audio/wav"
"github.com/hajimehoshi/ebiten/v2/ebitenutil"
raudio "github.com/hajimehoshi/ebiten/v2/examples/resources/audio"
riaudio "github.com/hajimehoshi/ebiten/v2/examples/resources/images/audio"
"github.com/hajimehoshi/ebiten/v2/inpututil"
)
const (
screenWidth = 640
screenHeight = 480
sampleRate = 32000
)
var (
playerBarColor = color.RGBA{0x80, 0x80, 0x80, 0xff}
playerCurrentColor = color.RGBA{0xff, 0xff, 0xff, 0xff}
)
var (
playButtonPosition image.Point
alertButtonPosition image.Point
playButtonImage *ebiten.Image
pauseButtonImage *ebiten.Image
alertButtonImage *ebiten.Image
)
func init() {
img, _, err := image.Decode(bytes.NewReader(riaudio.Play_png))
if err != nil {
panic(err)
}
playButtonImage = ebiten.NewImageFromImage(img)
img, _, err = image.Decode(bytes.NewReader(riaudio.Pause_png))
if err != nil {
panic(err)
}
pauseButtonImage = ebiten.NewImageFromImage(img)
img, _, err = image.Decode(bytes.NewReader(riaudio.Alert_png))
if err != nil {
panic(err)
}
alertButtonImage = ebiten.NewImageFromImage(img)
const buttonPadding = 16
w, _ := playButtonImage.Size()
playButtonPosition.X = (screenWidth - w*2 + buttonPadding*1) / 2
playButtonPosition.Y = screenHeight - 160
alertButtonPosition.X = playButtonPosition.X + w + buttonPadding
alertButtonPosition.Y = playButtonPosition.Y
}
type musicType int
const (
typeOgg musicType = iota
typeMP3
)
func (t musicType) String() string {
switch t {
case typeOgg:
return "Ogg"
case typeMP3:
return "MP3"
default:
panic("not reached")
}
}
// Player represents the current audio state.
type Player struct {
audioContext *audio.Context
audioPlayer *audio.Player
current time.Duration
total time.Duration
seBytes []byte
seCh chan []byte
volume128 int
musicType musicType
}
func playerBarRect() (x, y, w, h int) {
w, h = 600, 8
x = (screenWidth - w) / 2
y = screenHeight - h - 16
return
}
func NewPlayer(audioContext *audio.Context, musicType musicType) (*Player, error) {
type audioStream interface {
io.ReadSeeker
Length() int64
}
const bytesPerSample = 4 // TODO: This should be defined in audio package
var s audioStream
switch musicType {
case typeOgg:
var err error
s, err = vorbis.Decode(audioContext, bytes.NewReader(raudio.Ragtime_ogg))
if err != nil {
return nil, err
}
case typeMP3:
var err error
s, err = mp3.Decode(audioContext, bytes.NewReader(raudio.Ragtime_mp3))
if err != nil {
return nil, err
}
default:
panic("not reached")
}
p, err := audio.NewPlayer(audioContext, s)
if err != nil {
return nil, err
}
player := &Player{
audioContext: audioContext,
audioPlayer: p,
total: time.Second * time.Duration(s.Length()) / bytesPerSample / sampleRate,
volume128: 128,
seCh: make(chan []byte),
musicType: musicType,
}
if player.total == 0 {
player.total = 1
}
player.audioPlayer.Play()
go func() {
s, err := wav.Decode(audioContext, bytes.NewReader(raudio.Jab_wav))
if err != nil {
log.Fatal(err)
return
}
b, err := ioutil.ReadAll(s)
if err != nil {
log.Fatal(err)
return
}
player.seCh <- b
}()
return player, nil
}
func (p *Player) Close() error {
return p.audioPlayer.Close()
}
func (p *Player) update() error {
select {
case p.seBytes = <-p.seCh:
close(p.seCh)
p.seCh = nil
default:
}
if p.audioPlayer.IsPlaying() {
p.current = p.audioPlayer.Current()
}
p.seekBarIfNeeded()
p.switchPlayStateIfNeeded()
p.playSEIfNeeded()
p.updateVolumeIfNeeded()
if inpututil.IsKeyJustPressed(ebiten.KeyU) {
b := ebiten.IsRunnableOnUnfocused()
ebiten.SetRunnableOnUnfocused(!b)
}
return nil
}
func (p *Player) shouldPlaySE() bool {
if p.seBytes == nil {
// Bytes for the SE is not loaded yet.
return false
}
if inpututil.IsKeyJustPressed(ebiten.KeyP) {
return true
}
r := image.Rectangle{
Min: alertButtonPosition,
Max: alertButtonPosition.Add(image.Pt(alertButtonImage.Size())),
}
if image.Pt(ebiten.CursorPosition()).In(r) {
if inpututil.IsMouseButtonJustPressed(ebiten.MouseButtonLeft) {
return true
}
}
for _, id := range inpututil.JustPressedTouchIDs() {
if image.Pt(ebiten.TouchPosition(id)).In(r) {
return true
}
}
return false
}
func (p *Player) playSEIfNeeded() {
if !p.shouldPlaySE() {
return
}
sePlayer := audio.NewPlayerFromBytes(p.audioContext, p.seBytes)
sePlayer.Play()
}
func (p *Player) updateVolumeIfNeeded() {
if ebiten.IsKeyPressed(ebiten.KeyZ) {
p.volume128--
}
if ebiten.IsKeyPressed(ebiten.KeyX) {
p.volume128++
}
if p.volume128 < 0 {
p.volume128 = 0
}
if 128 < p.volume128 {
p.volume128 = 128
}
p.audioPlayer.SetVolume(float64(p.volume128) / 128)
}
func (p *Player) shouldSwitchPlayStateIfNeeded() bool {
if inpututil.IsKeyJustPressed(ebiten.KeyS) {
return true
}
r := image.Rectangle{
Min: playButtonPosition,
Max: playButtonPosition.Add(image.Pt(playButtonImage.Size())),
}
if image.Pt(ebiten.CursorPosition()).In(r) {
if inpututil.IsMouseButtonJustPressed(ebiten.MouseButtonLeft) {
return true
}
}
for _, id := range inpututil.JustPressedTouchIDs() {
if image.Pt(ebiten.TouchPosition(id)).In(r) {
return true
}
}
return false
}
func (p *Player) switchPlayStateIfNeeded() {
if !p.shouldSwitchPlayStateIfNeeded() {
return
}
if p.audioPlayer.IsPlaying() {
p.audioPlayer.Pause()
return
}
p.audioPlayer.Play()
}
func justPressedPosition() (int, int, bool) {
if inpututil.IsMouseButtonJustPressed(ebiten.MouseButtonLeft) {
x, y := ebiten.CursorPosition()
return x, y, true
}
if ts := inpututil.JustPressedTouchIDs(); len(ts) > 0 {
x, y := ebiten.TouchPosition(ts[0])
return x, y, true
}
return 0, 0, false
}
func (p *Player) seekBarIfNeeded() {
// Calculate the next seeking position from the current cursor position.
x, y, ok := justPressedPosition()
if !ok {
return
}
bx, by, bw, bh := playerBarRect()
const padding = 4
if y < by-padding || by+bh+padding <= y {
return
}
if x < bx || bx+bw <= x {
return
}
pos := time.Duration(x-bx) * p.total / time.Duration(bw)
p.current = pos
p.audioPlayer.Seek(pos)
}
func (p *Player) draw(screen *ebiten.Image) {
// Draw the bar.
x, y, w, h := playerBarRect()
ebitenutil.DrawRect(screen, float64(x), float64(y), float64(w), float64(h), playerBarColor)
// Draw the cursor on the bar.
c := p.current
cw, ch := 8, 20
cx := int(time.Duration(w)*c/p.total) + x - cw/2
cy := y - (ch-h)/2
ebitenutil.DrawRect(screen, float64(cx), float64(cy), float64(cw), float64(ch), playerCurrentColor)
// Compose the curren time text.
m := (c / time.Minute) % 100
s := (c / time.Second) % 60
currentTimeStr := fmt.Sprintf("%02d:%02d", m, s)
// Draw buttons
op := &ebiten.DrawImageOptions{}
op.GeoM.Translate(float64(playButtonPosition.X), float64(playButtonPosition.Y))
if p.audioPlayer.IsPlaying() {
screen.DrawImage(pauseButtonImage, op)
} else {
screen.DrawImage(playButtonImage, op)
}
op.GeoM.Reset()
op.GeoM.Translate(float64(alertButtonPosition.X), float64(alertButtonPosition.Y))
screen.DrawImage(alertButtonImage, op)
// Draw the debug message.
msg := fmt.Sprintf(`TPS: %0.2f
Press S to toggle Play/Pause
Press P to play SE
Press Z or X to change volume of the music
Press U to switch the runnable-on-unfocused state
Press A to switch Ogg and MP3 (Current: %s)
Current Time: %s
Current Volume: %d/128
Type: %s`, ebiten.CurrentTPS(), p.musicType,
currentTimeStr, int(p.audioPlayer.Volume()*128), p.musicType)
ebitenutil.DebugPrint(screen, msg)
}
type Game struct {
musicPlayer *Player
musicPlayerCh chan *Player
errCh chan error
}
func NewGame() (*Game, error) {
audioContext := audio.NewContext(sampleRate)
m, err := NewPlayer(audioContext, typeOgg)
if err != nil {
return nil, err
}
return &Game{
musicPlayer: m,
musicPlayerCh: make(chan *Player),
errCh: make(chan error),
}, nil
}
func (g *Game) Update() error {
select {
case p := <-g.musicPlayerCh:
g.musicPlayer = p
case err := <-g.errCh:
return err
default:
}
if g.musicPlayer != nil && inpututil.IsKeyJustPressed(ebiten.KeyA) {
var t musicType
switch g.musicPlayer.musicType {
case typeOgg:
t = typeMP3
case typeMP3:
t = typeOgg
default:
panic("not reached")
}
g.musicPlayer.Close()
g.musicPlayer = nil
go func() {
p, err := NewPlayer(audio.CurrentContext(), t)
if err != nil {
g.errCh <- err
return
}
g.musicPlayerCh <- p
}()
}
if g.musicPlayer != nil {
if err := g.musicPlayer.update(); err != nil {
return err
}
}
return nil
}
func (g *Game) Draw(screen *ebiten.Image) {
if g.musicPlayer != nil {
g.musicPlayer.draw(screen)
}
}
func (g *Game) Layout(outsideWidth, outsideHeight int) (int, int) {
return screenWidth, screenHeight
}
func main() {
ebiten.SetWindowSize(screenWidth, screenHeight)
ebiten.SetWindowTitle("Audio (Ebiten Demo)")
g, err := NewGame()
if err != nil {
log.Fatal(err)
}
if err := ebiten.RunGame(g); err != nil {
log.Fatal(err)
}
}