ebiten/examples/audio/main.go
Hajime Hoshi e16a4cd85c examples: Use RunGame
Updates #1111
2020-04-12 19:03:04 +09:00

349 lines
7.3 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 jsgo
// This is an example to implement an audio player.
// See examples/wav for a simpler example to play a sound file.
package main
import (
"fmt"
"image/color"
"io/ioutil"
"log"
"time"
"github.com/hajimehoshi/ebiten"
"github.com/hajimehoshi/ebiten/audio"
"github.com/hajimehoshi/ebiten/audio/mp3"
"github.com/hajimehoshi/ebiten/audio/vorbis"
"github.com/hajimehoshi/ebiten/audio/wav"
"github.com/hajimehoshi/ebiten/ebitenutil"
raudio "github.com/hajimehoshi/ebiten/examples/resources/audio"
"github.com/hajimehoshi/ebiten/inpututil"
)
const (
screenWidth = 320
screenHeight = 240
sampleRate = 22050
)
var (
playerBarColor = color.RGBA{0x80, 0x80, 0x80, 0xff}
playerCurrentColor = color.RGBA{0xff, 0xff, 0xff, 0xff}
)
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 = 300, 4
x = (screenWidth - w) / 2
y = screenHeight - h - 16
return
}
func NewPlayer(audioContext *audio.Context, musicType musicType) (*Player, error) {
type audioStream interface {
audio.ReadSeekCloser
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, audio.BytesReadSeekCloser(raudio.Ragtime_ogg))
if err != nil {
return nil, err
}
case typeMP3:
var err error
s, err = mp3.Decode(audioContext, audio.BytesReadSeekCloser(raudio.Classic_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, audio.BytesReadSeekCloser(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) playSEIfNeeded() {
if p.seBytes == nil {
// Bytes for the SE is not loaded yet.
return
}
if !inpututil.IsKeyJustPressed(ebiten.KeyP) {
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) switchPlayStateIfNeeded() {
if !inpututil.IsKeyJustPressed(ebiten.KeyS) {
return
}
if p.audioPlayer.IsPlaying() {
p.audioPlayer.Pause()
return
}
p.audioPlayer.Play()
}
func (p *Player) seekBarIfNeeded() {
if !inpututil.IsMouseButtonJustPressed(ebiten.MouseButtonLeft) {
return
}
// Calculate the next seeking position from the current cursor position.
x, y := ebiten.CursorPosition()
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 := 4, 10
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 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 Time: %s
Current Volume: %d/128
Type: %s`, ebiten.CurrentTPS(), 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, err := audio.NewContext(sampleRate)
if err != nil {
return nil, err
}
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(screen *ebiten.Image) 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*2, screenHeight*2)
ebiten.SetWindowTitle("Audio (Ebiten Demo)")
g, err := NewGame()
if err != nil {
log.Fatal(err)
}
if err := ebiten.RunGame(g); err != nil {
log.Fatal(err)
}
}