audiobank now returns samples in floats

src/net/torvald/terrarum/audio/AudioBank.kt

@@ -25,7 +25,7 @@ abstract class AudioBank : Disposable {
     abstract val totalSizeInSamples: Long
     abstract fun currentPositionInSamples(): Long
 
-    abstract fun readBytes(buffer: ByteArray): Int
+    abstract fun readSamples(bufferL: FloatArray, bufferR: FloatArray): Int
     abstract fun reset()
 
     abstract val songFinishedHook: (AudioBank) -> Unit

src/net/torvald/terrarum/audio/AudioProcessBuf.kt

@@ -25,7 +25,7 @@ private data class Frac(var nom: Int, val denom: Int) {
  *
  * Created by minjaesong on 2023-11-17.
  */
-class AudioProcessBuf(val inputSamplingRate: Int, val audioReadFun: (ByteArray) -> Int?, val onAudioFinished: () -> Unit) {
+class AudioProcessBuf(val inputSamplingRate: Int, val audioReadFun: (FloatArray, FloatArray) -> Int?, val onAudioFinished: () -> Unit) {
 
     var pitch: Float = 1f
     var playbackSpeed = 1f
@@ -144,7 +144,8 @@ class AudioProcessBuf(val inputSamplingRate: Int, val audioReadFun: (ByteArray)
     private val fmidR = FloatArray((fetchSize * 2 + 1.0).toInt())
     private val foutL = FloatArray(internalBufferSize) // 640 for (44100, 48000), 512 for (48000, 48000) with BUFFER_SIZE = 512 * 4
     private val foutR = FloatArray(internalBufferSize) // 640 for (44100, 48000), 512 for (48000, 48000) with BUFFER_SIZE = 512 * 4
-    private val readBuf = ByteArray(fetchSize * 4)
+    private val readBufL = FloatArray(fetchSize)
+    private val readBufR = FloatArray(fetchSize)
 
     init {
 //        printdbg(this, "App.audioMixerBufferSize=${App.audioBufferSize}")
@@ -160,28 +161,26 @@ class AudioProcessBuf(val inputSamplingRate: Int, val audioReadFun: (ByteArray)
         val readCount = if (samplesInBuf < App.audioBufferSize) fetchSize else 0
         val writeCount = (readCount / q).roundToInt()
 
-        fun getFromReadBuf(i: Int, bytesRead: Int) = if (i < bytesRead) readBuf[i].toUint() else 0
+        fun getFromReadBufL(index: Int, samplesRead: Int) = if (index < samplesRead) readBufL[index] else 0f
+        fun getFromReadBufR(index: Int, samplesRead: Int) = if (index < samplesRead) readBufR[index] else 0f
 
         if (readCount > 0) {
             try {
                 shift(finL, readCount)
                 shift(finR, readCount)
 
-                val bytesRead = audioReadFun(readBuf)
+                val samplesRead = audioReadFun(readBufL, readBufR)
 //                printdbg(this, "Reading audio $readCount samples, got ${bytesRead?.div(4)} samples")
 
-                if (bytesRead == null || bytesRead <= 0) {
+                if (samplesRead == null || samplesRead <= 0) {
 //                    printdbg(this, "Music finished; bytesRead = $bytesRead")
 
                     onAudioFinished()
                 }
                 else {
                     for (c in 0 until readCount) {
-                        val sl = (getFromReadBuf(4 * c + 0, bytesRead) or getFromReadBuf(4 * c + 1, bytesRead).shl(8)).toShort()
-                        val sr = (getFromReadBuf(4 * c + 2, bytesRead) or getFromReadBuf(4 * c + 3, bytesRead).shl(8)).toShort()
-
-                        val fl = sl / 32767f
-                        val fr = sr / 32767f
+                        val fl = getFromReadBufL(c, samplesRead)
+                        val fr = getFromReadBufR(c, samplesRead)
 
                         finL[2 * PADSIZE + c] = fl
                         finR[2 * PADSIZE + c] = fr
@@ -217,6 +216,7 @@ class AudioProcessBuf(val inputSamplingRate: Int, val audioReadFun: (ByteArray)
 //        printdbg(this, "phase = $fPhaseL")
     }
 
+    // return the copy of the foutL/R
     fun getLR(): Pair<FloatArray, FloatArray> {
         val samplesInBuf = validSamplesInBuf
 

src/net/torvald/terrarum/audio/MixerTrackProcessor.kt

@@ -88,29 +88,33 @@ class MixerTrackProcessor(bufferSize: Int, val rate: Int, val track: TerrarumAud
 
     private fun allocateStreamBuf(track: TerrarumAudioMixerTrack) {
         printdbg("Allocating a StreamBuf with rate ${track.currentTrack!!.samplingRate}")
-        streamBuf = AudioProcessBuf(track.currentTrack!!.samplingRate, { buffer ->
-            var bytesRead = track.currentTrack?.readBytes(buffer) ?: 0
+        streamBuf = AudioProcessBuf(track.currentTrack!!.samplingRate, { bufL, bufR ->
+            var samplesRead = track.currentTrack?.readSamples(bufL, bufR) ?: 0
 
             // do gapless fetch if there is space in the buffer
-            if (track.doGaplessPlayback && bytesRead < buffer.size) {
+            if (track.doGaplessPlayback && samplesRead < bufL.size) {
                 track.currentTrack?.reset()
                 track.pullNextTrack()
 
-                bytesRead += read0(buffer, bytesRead)
+                samplesRead += read00(bufL, bufR, samplesRead)
             }
 
-            bytesRead
+            samplesRead
         }, { purgeStreamBuf() }).also {
 //            it.jitterMode = jitterMode
 //            it.jitterIntensity = jitterIntensity
         }
     }
 
-    private fun read0(buffer: ByteArray, bytesRead: Int): Int {
-        val tmpBuf = ByteArray(buffer.size - bytesRead)
-        val newRead = track.currentTrack?.readBytes(tmpBuf) ?: 0
+    private fun read00(bufL: FloatArray, bufR: FloatArray, samplesRead: Int): Int {
+        val bufSize = bufL.size - samplesRead
+        val tmpBufL = FloatArray(bufSize)
+        val tmpBufR = FloatArray(bufSize)
 
-        System.arraycopy(tmpBuf, 0, buffer, bytesRead, tmpBuf.size)
+        val newRead = track.currentTrack?.readSamples(tmpBufL, tmpBufR) ?: 0
+
+        System.arraycopy(tmpBufL, 0, bufL, samplesRead, tmpBufL.size)
+        System.arraycopy(tmpBufR, 0, bufR, samplesRead, tmpBufR.size)
 
         return newRead
     }

src/net/torvald/terrarum/audio/MusicContainer.kt

@@ -12,6 +12,7 @@ import javazoom.jl.decoder.Bitstream
 import net.torvald.reflection.extortField
 import net.torvald.reflection.forceInvoke
 import net.torvald.terrarum.App.printdbg
+import net.torvald.terrarum.serialise.toUint
 import net.torvald.unsafe.UnsafeHelper
 import net.torvald.unsafe.UnsafePtr
 import java.io.File
@@ -121,16 +122,38 @@ class MusicContainer(
         }
     }
 
-    private fun read0(buffer: ByteArray, bytesRead: Int): Int {
-        val tmpBuf = ByteArray(buffer.size - bytesRead)
-        val newRead = readBytes(tmpBuf)
+    override fun readSamples(bufferL: FloatArray, bufferR: FloatArray): Int {
+        assert(bufferL.size == bufferR.size)
 
-        System.arraycopy(tmpBuf, 0, buffer, bytesRead, tmpBuf.size)
+        val byteSize = bufferL.size * bytesPerSample
+        val bytesBuf = ByteArray(byteSize)
+        val bytesRead = readBytes(bytesBuf)
+        val samplesRead = bytesRead / bytesPerSample
 
-        return newRead
+        if (channels == 2) {
+            for (i in 0 until samplesRead) {
+                val sl = (bytesBuf[i * 4 + 0].toUint() or bytesBuf[i * 4 + 1].toUint().shl(8)).toShort()
+                val sr = (bytesBuf[i * 4 + 2].toUint() or bytesBuf[i * 4 + 3].toUint().shl(8)).toShort()
+                val fl = sl / 32767f
+                val fr = sr / 32767f
+                bufferL[i] = fl
+                bufferR[i] = fr
+            }
+        }
+        else if (channels == 1) {
+            for (i in 0 until samplesRead) {
+                val s = (bytesBuf[i * 2 + 0].toUint() or bytesBuf[i * 2 + 1].toUint().shl(8)).toShort()
+                val f = s / 32767f
+                bufferL[i] = f
+                bufferR[i] = f
+            }
+        }
+        else throw IllegalStateException("Unsupported channel count: $channels")
+
+        return samplesRead
     }
 
-    override fun readBytes(buffer: ByteArray): Int {
+    private fun readBytes(buffer: ByteArray): Int {
         if (soundBuf == null) {
             val bytesRead = gdxMusic.forceInvoke<Int>("read", arrayOf(buffer)) ?: 0
             samplesReadCount += bytesRead / bytesPerSample