libgambatte-patches/svn537/0004-Fix-sound-DC-levels.patch

   1 From 607d3e252c43d67cea54ec222ef1767a86b3660b Mon Sep 17 00:00:00 2001
   2 From: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
   3 Date: Thu, 5 Dec 2013 08:48:21 +0200
   4 Subject: [PATCH 4/9] Fix sound DC levels
   5
   6 This was causing popping in Mega Man (I)
   7 ---
   8  libgambatte/src/sound/channel1.cpp | 6 +++---
   9  libgambatte/src/sound/channel2.cpp | 6 +++---
  10  libgambatte/src/sound/channel3.cpp | 8 ++++----
  11  libgambatte/src/sound/channel4.cpp | 4 ++--
  12  4 files changed, 12 insertions(+), 12 deletions(-)
  13
  14 diff --git a/libgambatte/src/sound/channel1.cpp b/libgambatte/src/sound/channel1.cpp
  15 index c517965..dd83894 100644
  16 --- a/libgambatte/src/sound/channel1.cpp
  17 +++ b/libgambatte/src/sound/channel1.cpp
  18 @@ -218,13 +218,13 @@ void Channel1::loadState(SaveState const &state) {
  19
  20  void Channel1::update(uint_least32_t *buf, unsigned const soBaseVol, unsigned cycles) {
  21         unsigned const outBase = envelopeUnit_.dacIsOn() ? soBaseVol & soMask_ : 0;
  22 -       unsigned const outLow = outBase * (0 - 15ul);
  23         unsigned const endCycles = cycleCounter_ + cycles;
  24
  25         for (;;) {
  26                 unsigned const outHigh = master_
  27 -                                           ? outBase * (envelopeUnit_.getVolume() * 2 - 15ul)
  28 -                                           : outLow;
  29 +                                           ? outBase * (envelopeUnit_.getVolume())
  30 +                                           : 0;
  31 +               unsigned const outLow = -outHigh;
  32                 unsigned const nextMajorEvent = std::min(nextEventUnit_->counter(), endCycles);
  33                 unsigned out = dutyUnit_.isHighState() ? outHigh : outLow;
  34
  35 diff --git a/libgambatte/src/sound/channel2.cpp b/libgambatte/src/sound/channel2.cpp
  36 index f154249..6024d79 100644
  37 --- a/libgambatte/src/sound/channel2.cpp
  38 +++ b/libgambatte/src/sound/channel2.cpp
  39 @@ -122,13 +122,13 @@ void Channel2::loadState(SaveState const &state) {
  40
  41  void Channel2::update(uint_least32_t *buf, unsigned const soBaseVol, unsigned cycles) {
  42         unsigned const outBase = envelopeUnit_.dacIsOn() ? soBaseVol & soMask_ : 0;
  43 -       unsigned const outLow = outBase * (0 - 15ul);
  44         unsigned const endCycles = cycleCounter_ + cycles;
  45
  46         for (;;) {
  47                 unsigned const outHigh = master_
  48 -                                           ? outBase * (envelopeUnit_.getVolume() * 2 - 15ul)
  49 -                                           : outLow;
  50 +                                           ? outBase * (envelopeUnit_.getVolume())
  51 +                                           : 0;
  52 +               unsigned const outLow = -outHigh;
  53                 unsigned const nextMajorEvent = std::min(nextEventUnit->counter(), endCycles);
  54                 unsigned out = dutyUnit_.isHighState() ? outHigh : outLow;
  55
  56 diff --git a/libgambatte/src/sound/channel3.cpp b/libgambatte/src/sound/channel3.cpp
  57 index c583949..f25c96d 100644
  58 --- a/libgambatte/src/sound/channel3.cpp
  59 +++ b/libgambatte/src/sound/channel3.cpp
  60 @@ -156,8 +156,8 @@ void Channel3::update(uint_least32_t *buf, unsigned const soBaseVol, unsigned cy
  61                         unsigned const nextMajorEvent =
  62                                 std::min(lengthCounter_.counter(), endCycles);
  63                         unsigned out = master_
  64 -                               ? ((sampleBuf_ >> (~wavePos_ << 2 & 4) & 0xF) >> rshift_) * 2 - 15ul
  65 -                               : 0 - 15ul;
  66 +                               ? ((sampleBuf_ >> (~wavePos_ << 2 & 4) & 0xF) >> rshift_) * 2 - (15 >> rshift_)
  67 +                               : 0;
  68                         out *= outBase;
  69
  70                         while (waveCounter_ <= nextMajorEvent) {
  71 @@ -171,7 +171,7 @@ void Channel3::update(uint_least32_t *buf, unsigned const soBaseVol, unsigned cy
  72                                 ++wavePos_;
  73                                 wavePos_ &= 0x1F;
  74                                 sampleBuf_ = waveRam_[wavePos_ >> 1];
  75 -                               out = ((sampleBuf_ >> (~wavePos_ << 2 & 4) & 0xF) >> rshift_) * 2 - 15ul;
  76 +                               out = ((sampleBuf_ >> (~wavePos_ << 2 & 4) & 0xF) >> rshift_) * 2 - (15 >> rshift_);
  77                                 out *= outBase;
  78                         }
  79
  80 @@ -188,7 +188,7 @@ void Channel3::update(uint_least32_t *buf, unsigned const soBaseVol, unsigned cy
  81                                 break;
  82                 }
  83         } else {
  84 -               unsigned const out = outBase * (0 - 15ul);
  85 +               unsigned const out = 0;
  86                 *buf += out - prevOut_;
  87                 prevOut_ = out;
  88                 cycleCounter_ += cycles;
  89 diff --git a/libgambatte/src/sound/channel4.cpp b/libgambatte/src/sound/channel4.cpp
  90 index bc0a312..0abd4fb 100644
  91 --- a/libgambatte/src/sound/channel4.cpp
  92 +++ b/libgambatte/src/sound/channel4.cpp
  93 @@ -224,11 +224,11 @@ void Channel4::loadState(SaveState const &state) {
  94
  95  void Channel4::update(uint_least32_t *buf, unsigned const soBaseVol, unsigned cycles) {
  96         unsigned const outBase = envelopeUnit_.dacIsOn() ? soBaseVol & soMask_ : 0;
  97 -       unsigned const outLow = outBase * (0 - 15ul);
  98         unsigned const endCycles = cycleCounter_ + cycles;
  99
 100         for (;;) {
 101 -               unsigned const outHigh = outBase * (envelopeUnit_.getVolume() * 2 - 15ul);
 102 +               unsigned const outHigh = outBase * (envelopeUnit_.getVolume());
 103 +               unsigned const outLow = -outHigh;
 104                 unsigned const nextMajorEvent = std::min(nextEventUnit_->counter(), endCycles);
 105                 unsigned out = lfsr_.isHighState() ? outHigh : outLow;
 106
 107 --
 108 2.1.3
 109