From b67c0837d8a79770d13d16d937e6fa50cd7fd1bc Mon Sep 17 00:00:00 2001
From: minjaesong <alswo9628@gmail.com>
Date: Wed, 24 Jan 2024 19:10:04 +0900
Subject: [PATCH] fix: track fader was applied at PRE instead of POST

---
 src/net/torvald/terrarum/audio/AudioProcessBuf.kt  |  8 +++++---
 .../torvald/terrarum/audio/MixerTrackProcessor.kt  | 14 +++++++++++---
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/src/net/torvald/terrarum/audio/AudioProcessBuf.kt b/src/net/torvald/terrarum/audio/AudioProcessBuf.kt
index b4daf6d8d..eb053d708 100644
--- a/src/net/torvald/terrarum/audio/AudioProcessBuf.kt
+++ b/src/net/torvald/terrarum/audio/AudioProcessBuf.kt
@@ -188,10 +188,12 @@ class AudioProcessBuf(val inputSamplingRate: Int, val audioReadFun: (ByteArray)
 //        printdbg(this, "phase = $fPhaseL")
     }
 
-    fun getLR(volume: Double): Pair<FloatArray, FloatArray> {
+    fun getLR(): Pair<FloatArray, FloatArray> {
         // copy into the out
-        val outL = FloatArray(App.audioBufferSize) { (foutL[it] * volume).toFloat() }
-        val outR = FloatArray(App.audioBufferSize) { (foutR[it] * volume).toFloat() }
+        val outL = FloatArray(App.audioBufferSize)
+        val outR = FloatArray(App.audioBufferSize)
+        System.arraycopy(foutL, 0, outL, 0, App.audioBufferSize)
+        System.arraycopy(foutR, 0, outR, 0, App.audioBufferSize)
         // shift bytes in the fout
         System.arraycopy(foutL, App.audioBufferSize, foutL, 0, validSamplesInBuf - App.audioBufferSize)
         System.arraycopy(foutR, App.audioBufferSize, foutR, 0, validSamplesInBuf - App.audioBufferSize)
diff --git a/src/net/torvald/terrarum/audio/MixerTrackProcessor.kt b/src/net/torvald/terrarum/audio/MixerTrackProcessor.kt
index c81ca35d8..a9185f715 100644
--- a/src/net/torvald/terrarum/audio/MixerTrackProcessor.kt
+++ b/src/net/torvald/terrarum/audio/MixerTrackProcessor.kt
@@ -184,8 +184,8 @@ class MixerTrackProcessor(bufferSize: Int, val rate: Int, val track: TerrarumAud
                 // add all up
                 sidechains.forEach { (side, mix) ->
                     for (i in samplesL1.indices) {
-                        samplesL1[i] += side.processor.fout1[0][i] * (mix * track.volume).toFloat()
-                        samplesR1[i] += side.processor.fout1[1][i] * (mix * track.volume).toFloat()
+                        samplesL1[i] += side.processor.fout1[0][i] * mix.toFloat()
+                        samplesR1[i] += side.processor.fout1[1][i] * mix.toFloat()
                     }
                 }
             }
@@ -198,7 +198,7 @@ class MixerTrackProcessor(bufferSize: Int, val rate: Int, val track: TerrarumAud
                 bufEmpty = true
             }
             else {
-                streamBuf!!.getLR(track.volume).let {
+                streamBuf!!.getLR().let {
                     samplesL1 = it.first
                     samplesR1 = it.second
                 }
@@ -225,6 +225,14 @@ class MixerTrackProcessor(bufferSize: Int, val rate: Int, val track: TerrarumAud
                 }
 
 
+                // apply fader at post
+                fout1.forEach { ch ->
+                    ch.forEachIndexed { index, sample ->
+                        ch[index] = (sample * track.volume).toFloat()
+                    }
+                }
+
+
                 // scan the finished sample for mapping signal level and clipping detection
                 fout1.map { it.maxOf { it.absoluteValue } }.forEachIndexed { index, fl ->
                     maxSigLevel[index] = fl.toDouble()