hayai/vendor/github.com/hajimehoshi/oto/driver_openal.go
2024-12-21 17:26:50 +01:00

263 lines
7.1 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 freebsd openbsd
// +build !js
// +build !android
package oto
// #cgo freebsd pkg-config: openal
// #cgo openbsd pkg-config: openal
//
// #include <stdint.h>
//
// #ifdef __APPLE__
// #include <OpenAL/al.h>
// #include <OpenAL/alc.h>
// #else
// #include <AL/al.h>
// #include <AL/alc.h>
// #endif
//
// static uintptr_t _alcOpenDevice(const ALCchar* name) {
// return (uintptr_t)alcOpenDevice(name);
// }
//
// static ALCboolean _alcCloseDevice(uintptr_t device) {
// return alcCloseDevice((void*)device);
// }
//
// static uintptr_t _alcCreateContext(uintptr_t device, const ALCint* attrList) {
// return (uintptr_t)alcCreateContext((void*)device, attrList);
// }
//
// static ALCenum _alcGetError(uintptr_t device) {
// return alcGetError((void*)device);
// }
//
// static void _alcMakeContextCurrent(uintptr_t context) {
// alcMakeContextCurrent((void*)context);
// }
//
// static void _alcDestroyContext(uintptr_t context) {
// alcDestroyContext((void*)context);
// }
import "C"
import (
"errors"
"fmt"
"runtime"
"unsafe"
)
// As x/mobile/exp/audio/al is broken on macOS (https://github.com/golang/go/issues/15075),
// and that doesn't support FreeBSD, use OpenAL directly here.
type driver struct {
// alContext represents a pointer to ALCcontext. The type is uintptr since the value
// can be 0x18 on macOS, which is invalid as a pointer value, and this might cause
// GC errors.
alContext alContext
alDevice alDevice
alDeviceName string
alSource C.ALuint
sampleRate int
isClosed bool
alFormat C.ALenum
bufs []C.ALuint
tmp []byte
bufferSize int
}
// alContext is a pointer to OpenAL context.
// The value is not unsafe.Pointer for C.ALCcontext but uintptr,
// because device pointer value can be an invalid value as a pointer on macOS,
// and Cgo pointer checker complains (#65).
type alContext uintptr
// alDevice is a pointer to OpenAL device.
type alDevice uintptr
func (a alDevice) getError() error {
switch c := C._alcGetError(C.uintptr_t(a)); c {
case C.ALC_NO_ERROR:
return nil
case C.ALC_INVALID_DEVICE:
return errors.New("OpenAL error: invalid device")
case C.ALC_INVALID_CONTEXT:
return errors.New("OpenAL error: invalid context")
case C.ALC_INVALID_ENUM:
return errors.New("OpenAL error: invalid enum")
case C.ALC_INVALID_VALUE:
return errors.New("OpenAL error: invalid value")
case C.ALC_OUT_OF_MEMORY:
return errors.New("OpenAL error: out of memory")
default:
return fmt.Errorf("OpenAL error: code %d", c)
}
}
func alFormat(channelNum, bitDepthInBytes int) C.ALenum {
switch {
case channelNum == 1 && bitDepthInBytes == 1:
return C.AL_FORMAT_MONO8
case channelNum == 1 && bitDepthInBytes == 2:
return C.AL_FORMAT_MONO16
case channelNum == 2 && bitDepthInBytes == 1:
return C.AL_FORMAT_STEREO8
case channelNum == 2 && bitDepthInBytes == 2:
return C.AL_FORMAT_STEREO16
}
panic(fmt.Sprintf("oto: invalid channel num (%d) or bytes per sample (%d)", channelNum, bitDepthInBytes))
}
const numBufs = 2
func newDriver(sampleRate, channelNum, bitDepthInBytes, bufferSizeInBytes int) (tryWriteCloser, error) {
name := C.alcGetString(nil, C.ALC_DEFAULT_DEVICE_SPECIFIER)
d := alDevice(C._alcOpenDevice((*C.ALCchar)(name)))
if d == 0 {
return nil, fmt.Errorf("oto: alcOpenDevice must not return null")
}
c := alContext(C._alcCreateContext(C.uintptr_t(d), nil))
if c == 0 {
return nil, fmt.Errorf("oto: alcCreateContext must not return null")
}
// Don't check getError until making the current context is done.
// Linux might fail this check even though it succeeds (hajimehoshi/ebiten#204).
C._alcMakeContextCurrent(C.uintptr_t(c))
if err := d.getError(); err != nil {
return nil, fmt.Errorf("oto: Activate: %v", err)
}
s := C.ALuint(0)
C.alGenSources(1, &s)
if err := d.getError(); err != nil {
return nil, fmt.Errorf("oto: NewSource: %v", err)
}
p := &driver{
alContext: c,
alDevice: d,
alSource: s,
alDeviceName: C.GoString((*C.char)(name)),
sampleRate: sampleRate,
alFormat: alFormat(channelNum, bitDepthInBytes),
bufs: make([]C.ALuint, numBufs),
bufferSize: bufferSizeInBytes,
}
runtime.SetFinalizer(p, (*driver).Close)
C.alGenBuffers(C.ALsizei(numBufs), &p.bufs[0])
C.alSourcePlay(p.alSource)
if err := d.getError(); err != nil {
return nil, fmt.Errorf("oto: Play: %v", err)
}
return p, nil
}
func (p *driver) TryWrite(data []byte) (int, error) {
if err := p.alDevice.getError(); err != nil {
return 0, fmt.Errorf("oto: starting Write: %v", err)
}
n := min(len(data), max(0, p.bufferSize-len(p.tmp)))
p.tmp = append(p.tmp, data[:n]...)
if len(p.tmp) < p.bufferSize {
return n, nil
}
pn := C.ALint(0)
C.alGetSourcei(p.alSource, C.AL_BUFFERS_PROCESSED, &pn)
if pn > 0 {
bufs := make([]C.ALuint, pn)
C.alSourceUnqueueBuffers(p.alSource, C.ALsizei(len(bufs)), &bufs[0])
if err := p.alDevice.getError(); err != nil {
return 0, fmt.Errorf("oto: UnqueueBuffers: %v", err)
}
p.bufs = append(p.bufs, bufs...)
}
if len(p.bufs) == 0 {
return n, nil
}
buf := p.bufs[0]
p.bufs = p.bufs[1:]
C.alBufferData(buf, p.alFormat, unsafe.Pointer(&p.tmp[0]), C.ALsizei(p.bufferSize), C.ALsizei(p.sampleRate))
C.alSourceQueueBuffers(p.alSource, 1, &buf)
if err := p.alDevice.getError(); err != nil {
return 0, fmt.Errorf("oto: QueueBuffer: %v", err)
}
state := C.ALint(0)
C.alGetSourcei(p.alSource, C.AL_SOURCE_STATE, &state)
if state == C.AL_STOPPED || state == C.AL_INITIAL {
C.alSourceRewind(p.alSource)
C.alSourcePlay(p.alSource)
if err := p.alDevice.getError(); err != nil {
return 0, fmt.Errorf("oto: Rewind or Play: %v", err)
}
}
p.tmp = nil
return n, nil
}
func (p *driver) Close() error {
if err := p.alDevice.getError(); err != nil {
return fmt.Errorf("oto: starting Close: %v", err)
}
if p.isClosed {
return nil
}
n := C.ALint(0)
C.alGetSourcei(p.alSource, C.AL_BUFFERS_QUEUED, &n)
if 0 < n {
bs := make([]C.ALuint, n)
C.alSourceUnqueueBuffers(p.alSource, C.ALsizei(len(bs)), &bs[0])
p.bufs = append(p.bufs, bs...)
}
C.alSourceStop(p.alSource)
C.alDeleteSources(1, &p.alSource)
if len(p.bufs) != 0 {
C.alDeleteBuffers(C.ALsizei(numBufs), &p.bufs[0])
}
C._alcDestroyContext(C.uintptr_t(p.alContext))
if err := p.alDevice.getError(); err != nil {
return fmt.Errorf("oto: CloseDevice: %v", err)
}
b := C._alcCloseDevice(C.uintptr_t(p.alDevice))
if b == C.ALC_FALSE {
return fmt.Errorf("oto: CloseDevice: %s failed to close", p.alDeviceName)
}
p.isClosed = true
runtime.SetFinalizer(p, nil)
return nil
}
func (d *driver) tryWriteCanReturnWithoutWaiting() bool {
return true
}