mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-09-20 21:32:20 +02:00
136 lines
2.9 KiB
Go
136 lines
2.9 KiB
Go
// Copyright 2015 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 js
|
|
|
|
package audio
|
|
|
|
import (
|
|
"github.com/gopherjs/gopherjs/js"
|
|
)
|
|
|
|
// Keep this so as not to be destroyed by GC.
|
|
var node js.Object
|
|
var context js.Object
|
|
|
|
const bufferSize = 1024
|
|
const SampleRate = 44100
|
|
|
|
type channel struct {
|
|
l []float32
|
|
r []float32
|
|
}
|
|
|
|
var channels = make([]*channel, 16)
|
|
|
|
func init() {
|
|
for i, _ := range channels {
|
|
channels[i] = &channel{
|
|
l: []float32{},
|
|
r: []float32{},
|
|
}
|
|
}
|
|
}
|
|
|
|
func min(a, b int) int {
|
|
if a < b {
|
|
return a
|
|
}
|
|
return b
|
|
}
|
|
|
|
var currentBytes = 0
|
|
|
|
func CurrentBytes() int {
|
|
return currentBytes
|
|
}
|
|
|
|
func Init() {
|
|
context = js.Global.Get("AudioContext").New()
|
|
// TODO: ScriptProcessorNode will be replaced with Audio WebWorker.
|
|
// https://developer.mozilla.org/ja/docs/Web/API/ScriptProcessorNode
|
|
node = context.Call("createScriptProcessor", bufferSize, 0, 2)
|
|
node.Call("addEventListener", "audioprocess", func(e js.Object) {
|
|
defer func() {
|
|
currentBytes += bufferSize
|
|
}()
|
|
|
|
l := e.Get("outputBuffer").Call("getChannelData", 0)
|
|
r := e.Get("outputBuffer").Call("getChannelData", 1)
|
|
inputL := make([]float32, bufferSize)
|
|
inputR := make([]float32, bufferSize)
|
|
for _, ch := range channels {
|
|
if len(ch.l) == 0 {
|
|
continue
|
|
}
|
|
l := min(len(ch.l), bufferSize)
|
|
for i := 0; i < l; i++ {
|
|
inputL[i] += ch.l[i]
|
|
inputR[i] += ch.r[i]
|
|
}
|
|
// TODO: Use copyFromChannel?
|
|
usedLen := min(bufferSize, len(ch.l))
|
|
ch.l = ch.l[usedLen:]
|
|
ch.r = ch.r[usedLen:]
|
|
}
|
|
for i := 0; i < bufferSize; i++ {
|
|
// TODO: Use copyFromChannel?
|
|
if len(inputL) <= i {
|
|
l.SetIndex(i, 0)
|
|
r.SetIndex(i, 0)
|
|
continue
|
|
}
|
|
l.SetIndex(i, inputL[i])
|
|
r.SetIndex(i, inputR[i])
|
|
}
|
|
})
|
|
}
|
|
|
|
func Start() {
|
|
// TODO: For iOS, node should be connected with a buffer node.
|
|
node.Call("connect", context.Get("destination"))
|
|
}
|
|
|
|
func channelAt(i int) *channel {
|
|
if i == -1 {
|
|
for _, ch := range channels {
|
|
if 0 < len(ch.l) {
|
|
continue
|
|
}
|
|
return ch
|
|
}
|
|
return nil
|
|
}
|
|
ch := channels[i]
|
|
// TODO: Can we append even though all data is not consumed? Need game timer?
|
|
if 0 < len(ch.l) {
|
|
return nil
|
|
}
|
|
return ch
|
|
}
|
|
|
|
func Append(i int, l []float32, r []float32) bool {
|
|
// TODO: Mutex (especially for OpenAL)
|
|
if len(l) != len(r) {
|
|
panic("len(l) must equal to len(r)")
|
|
}
|
|
ch := channelAt(i)
|
|
if ch == nil {
|
|
return false
|
|
}
|
|
ch.l = append(ch.l, l...)
|
|
ch.r = append(ch.r, r...)
|
|
return true
|
|
}
|