fallback if no audio devices can be found

pkg/audio/sdl.go

@@ -6,11 +6,10 @@ package audio
 // void AudioData(void *userdata, Uint8 *stream, int len);
 import "C"
 import (
-	"encoding/binary"
 	"github.com/thelolagemann/gomeboy/internal/gameboy"
 	"github.com/veandco/go-sdl2/sdl"
-	"os"
 	"reflect"
+	"time"
 	"unsafe"
 )
 
@@ -76,6 +75,7 @@ func OpenAudio(g *gameboy.GameBoy, fb chan []byte) error {
 		}
 	}
 	frameBuffer = fb
+	gb = g
 
 	var err error
 	if audioDeviceID, err = sdl.OpenAudioDevice("", false, &sdl.AudioSpec{
@@ -85,25 +85,24 @@ func OpenAudio(g *gameboy.GameBoy, fb chan []byte) error {
 		Samples:  bufferSize,
 		Callback: sdl.AudioCallback(C.AudioData),
 	}, nil, 0); err != nil {
+		// if we can't initialize any audio, we need to fall back to a dummy driver
+		// otherwise there won't be any output
+		go func() {
+			dummyBuffer := make([]C.Uint8, bufferSize*4) // Assuming 4 bytes per sample (32-bit float)
+			ticker := time.NewTicker(time.Second / time.Duration(sampleRate/bufferSize))
+			defer ticker.Stop()
+
+			for range ticker.C {
+				if gb != nil {
+					AudioData(nil, (*C.Uint8)(unsafe.Pointer(&dummyBuffer[0])), C.int(len(dummyBuffer)))
+				}
+			}
+		}()
 		return err
 	}
-	err = initWavFile() // Create WAV file at audio start
-	if err != nil {
-		return err
-	}
-	gb = g
-	sdl.PauseAudioDevice(audioDeviceID, false)
-
-	return nil
-}
 
-func CloseAudio() error {
-	err := finalizeWavFile() // Close WAV file at audio stop
-	if err != nil {
-		return err
-	}
+	sdl.PauseAudioDevice(audioDeviceID, false)
 
-	sdl.CloseAudioDevice(audioDeviceID)
 	return nil
 }
 
@@ -112,81 +111,8 @@ var (
 )
 
 const (
-	bufferSize = 1634
-	sampleRate = 96000
-)
-
-const (
+	bufferSize   = 1634
+	sampleRate   = 96000
 	frameSize    = 144 * 160 * 3
 	maxArraySize = 144 * 160 * 4
 )
-
-var (
-	wavFile            *os.File
-	wavDataSize        uint32
-	wavInitialized     bool
-	audioSampleRate    = 96000 // Adjust to your emulator's sample rate
-	audioNumChannels   = 2     // Adjust to your emulator's number of channels (1 for mono, 2 for stereo)
-	audioBitsPerSample = 32    // Adjust to your emulator's bit depth per sample (typically 8 or 16)
-)
-
-func initWavFile() error {
-	var err error
-	wavFile, err = os.Create("output.wav")
-	if err != nil {
-		return err
-	}
-
-	// Write the WAV file header placeholder
-	var header [44]byte
-	copy(header[:4], "RIFF")
-	copy(header[8:12], "WAVE")
-	copy(header[12:16], "fmt ")
-	binary.LittleEndian.PutUint32(header[16:20], 16) // PCM header size
-	binary.LittleEndian.PutUint16(header[20:22], 1)  // Audio format (1 = PCM)
-	binary.LittleEndian.PutUint16(header[22:24], uint16(audioNumChannels))
-	binary.LittleEndian.PutUint32(header[24:28], uint32(audioSampleRate))
-	binary.LittleEndian.PutUint32(header[28:32], uint32(audioSampleRate*audioNumChannels*(audioBitsPerSample/8)))
-	binary.LittleEndian.PutUint16(header[32:34], uint16(audioNumChannels*(audioBitsPerSample/8)))
-	binary.LittleEndian.PutUint16(header[34:36], uint16(audioBitsPerSample))
-	copy(header[36:40], "data")
-	// Data chunk size placeholder (to be filled in later)
-	_, err = wavFile.Write(header[:])
-	if err != nil {
-		return err
-	}
-
-	wavInitialized = true
-	return nil
-}
-
-func finalizeWavFile() error {
-	if wavFile == nil {
-		return nil
-	}
-
-	// Update the file size and data chunk size in the header
-	_, err := wavFile.Seek(4, 0)
-	if err != nil {
-		return err
-	}
-	if err := binary.Write(wavFile, binary.LittleEndian, uint32(36+wavDataSize)); err != nil {
-		return err
-	}
-
-	_, err = wavFile.Seek(40, 0)
-	if err != nil {
-		return err
-	}
-	if err := binary.Write(wavFile, binary.LittleEndian, wavDataSize); err != nil {
-		return err
-	}
-
-	err = wavFile.Close()
-	if err != nil {
-		return err
-	}
-
-	wavFile = nil
-	return nil
-}