From 98e1771a832f0843d1a8be344894c0c77bd5f8fd Mon Sep 17 00:00:00 2001
From: khokh2001
Date: Wed, 29 Oct 2014 01:37:42 +0900
Subject: opl note limitation and octave overflow fixes

---
 src/i_oplmusic.c | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/src/i_oplmusic.c b/src/i_oplmusic.c
index a1e90506..bb9edcb4 100644
--- a/src/i_oplmusic.c
+++ b/src/i_oplmusic.c
@@ -734,9 +734,14 @@ static unsigned int FrequencyForVoice(opl_voice_t *voice)
 
     // Avoid possible overflow due to base note offset:
 
-    if (note > 0x7f)
+    while (note < 0)
     {
-        note = voice->note;
+        note += 12;
+    }
+    
+    while (note > 95)
+    {
+        note -= 12;
     }
 
     freq_index = 64 + 32 * note + voice->channel->bend;
@@ -770,14 +775,7 @@ static unsigned int FrequencyForVoice(opl_voice_t *voice)
 
     if (octave >= 7)
     {
-        if (sub_index < 5)
-        {
-            octave = 7;
-        }
-        else
-        {
-            octave = 6;
-        }
+        octave = 7;
     }
 
     // Calculate the resulting register value to use for the frequency.
-- 
cgit v1.2.3


From 0cada1cf6fd7b5cdcf41b5638b35d779b430efb8 Mon Sep 17 00:00:00 2001
From: khokh2001
Date: Wed, 29 Oct 2014 16:52:36 +0900
Subject: Update i_oplmusic.c

---
 src/i_oplmusic.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/i_oplmusic.c b/src/i_oplmusic.c
index bb9edcb4..45469dfb 100644
--- a/src/i_oplmusic.c
+++ b/src/i_oplmusic.c
@@ -715,10 +715,10 @@ static opl_voice_t *ReplaceExistingVoice(opl_channel_data_t *channel)
 static unsigned int FrequencyForVoice(opl_voice_t *voice)
 {
     genmidi_voice_t *gm_voice;
-    unsigned int freq_index;
+    signed int freq_index;
     unsigned int octave;
     unsigned int sub_index;
-    unsigned int note;
+    signed int note;
 
     note = voice->note;
 
@@ -754,6 +754,11 @@ static unsigned int FrequencyForVoice(opl_voice_t *voice)
         freq_index += (voice->current_instr->fine_tuning / 2) - 64;
     }
 
+    if (freq_index < 0)
+    {
+    	freq_index = 0;
+    }
+    
     // The first 7 notes use the start of the table, while
     // consecutive notes loop around the latter part.
 
-- 
cgit v1.2.3