ebiten/audio/vorbis/float32.go
Hajime Hoshi f0ef1ecad0 all: add float32 version of audio APIs
This change adds these APIs

 * (*audio.Context).NewPlayerF32
 * (*audio.Context).NewPlayerF32FromBytes
 * audio.NewInfiniteLoopF32
 * audio.NewInfiniteLoopWithIntroF32
 * audio.ResampleF32
 * mp3.DecodeF32
 * vorbis.DecodeF32
 * wav.DecodeF32

Closes #2160
2024-07-21 19:12:18 +09:00

81 lines
1.8 KiB
Go

// Copyright 2024 The Ebitengine 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 vorbis
import (
"io"
"math"
"github.com/jfreymuth/oggvorbis"
)
var _ io.ReadSeeker = (*float32BytesReadSeeker)(nil)
func newFloat32BytesReadSeeker(r *oggvorbis.Reader) *float32BytesReadSeeker {
return &float32BytesReadSeeker{r: r}
}
type float32BytesReadSeeker struct {
r *oggvorbis.Reader
fbuf []float32
pos int64
}
func (r *float32BytesReadSeeker) Read(buf []byte) (int, error) {
if len(buf) == 0 {
return 0, nil
}
l := max(len(buf)/4/r.r.Channels()*r.r.Channels(), 1)
if cap(r.fbuf) < l {
r.fbuf = make([]float32, l)
}
n, err := r.r.Read(r.fbuf[:l])
if err != nil && err != io.EOF {
return 0, err
}
for i := 0; i < n; i++ {
v := math.Float32bits(r.fbuf[i])
buf[4*i] = byte(v)
buf[4*i+1] = byte(v >> 8)
buf[4*i+2] = byte(v >> 16)
buf[4*i+3] = byte(v >> 24)
}
r.pos += int64(n * 4)
return n * 4, err
}
func (r *float32BytesReadSeeker) Seek(offset int64, whence int) (int64, error) {
sampleSize := int64(r.r.Channels()) * 4
offset = offset / sampleSize * sampleSize
switch whence {
case io.SeekStart:
case io.SeekCurrent:
offset += r.pos
case io.SeekEnd:
offset += r.r.Length()
}
r.pos = offset
if err := r.r.SetPosition(r.pos / sampleSize); err != nil {
return 0, err
}
return r.pos, nil
}