Fix issue with instrument type reading, change format slightly

Reduce the size of some things and reorder a few bytes
mdsitton · May 20, 2022 · 41ebab6 · 41ebab6
1 parent 0ed04e0
commit 41ebab6
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Showing 5 changed files with 40 additions and 16 deletions.
diff --git a/BChartConsts.cs b/BChartConsts.cs
@@ -71,16 +71,16 @@ public static class DrumNotes
         public const uint NOTE_MOD_KICK_2 = 8;
     }
 
-    public const uint INSTRUMENT_GUITAR = 0;
-    public const uint INSTRUMENT_GUITAR_SIX = 1;
-    public const uint INSTRUMENT_BASS = 2;
-    public const uint INSTRUMENT_BASS_SIX = 3;
-    public const uint INSTRUMENT_RHYTHM = 4;
-    public const uint INSTRUMENT_COOP = 5;
-    public const uint INSTRUMENT_KEYS = 6;
-    public const uint INSTRUMENT_DRUMS = 7;
-    public const uint INSTRUMENT_VOCALS = 8;
-    public const uint INSTRUMENT_UKN = 0xFFFF;
+    public const byte INSTRUMENT_GUITAR = 0;
+    public const byte INSTRUMENT_GUITAR_SIX = 1;
+    public const byte INSTRUMENT_BASS = 2;
+    public const byte INSTRUMENT_BASS_SIX = 3;
+    public const byte INSTRUMENT_RHYTHM = 4;
+    public const byte INSTRUMENT_COOP = 5;
+    public const byte INSTRUMENT_KEYS = 6;
+    public const byte INSTRUMENT_DRUMS = 7;
+    public const byte INSTRUMENT_VOCALS = 8;
+    public const byte INSTRUMENT_UKN = 0xFF;
 
     public static uint HeaderChunkName = BChartUtils.GetChunkNameToInt("BCHF");
     public static uint TempoChunkName = BChartUtils.GetChunkNameToInt("SYNC");

diff --git a/BChartReader.cs b/BChartReader.cs
@@ -212,7 +212,10 @@ public static void ReadDifficulty(Span<byte> data, Song song, Instrument inst)
     public static (Instrument inst, byte count) ReadInstrument(Span<byte> data)
     {
         int pos = 0;
-        return ((Instrument)data.ReadUInt32LE(ref pos), data.ReadByte(ref pos));
+        Instrument inst = BChartUtils.BChartToMoonInstrument(data.ReadByte(ref pos));
+        byte count = data.ReadByte(ref pos);
+
+        return (inst, count);
     }
 
     public static Song ReadBChart(string path)

diff --git a/BChartUtils.cs b/BChartUtils.cs
@@ -100,7 +100,7 @@ public static Difficulty BChartToMoonDiff(byte difficulty)
     /// </summary>
     /// <param name="instrument">Moonscraper instrument enum</param>
     /// <returns>BChart output instrument id</returns>
-    public static uint MoonInstrumentToBChart(Instrument instrument)
+    public static byte MoonInstrumentToBChart(Instrument instrument)
     {
         return instrument switch
         {
@@ -116,6 +116,27 @@ public static uint MoonInstrumentToBChart(Instrument instrument)
         };
     }
 
+    /// <summary>
+    /// Convert bchart instrument track id to the moonscraper instrument enum
+    /// </summary>
+    /// <param name="instrument">BChart instrument id</param>
+    /// <returns>Moonscraper instrument enum</returns>
+    public static Instrument BChartToMoonInstrument(byte instrument)
+    {
+        return instrument switch
+        {
+            BChartConsts.INSTRUMENT_GUITAR => Instrument.Guitar,
+            BChartConsts.INSTRUMENT_COOP => Instrument.GuitarCoop,
+            BChartConsts.INSTRUMENT_BASS => Instrument.Bass,
+            BChartConsts.INSTRUMENT_RHYTHM => Instrument.Rhythm,
+            BChartConsts.INSTRUMENT_KEYS => Instrument.Keys,
+            BChartConsts.INSTRUMENT_DRUMS => Instrument.Drums,
+            BChartConsts.INSTRUMENT_GUITAR_SIX => Instrument.GHLiveGuitar,
+            BChartConsts.INSTRUMENT_BASS_SIX => Instrument.GHLiveBass,
+            _ => Instrument.Unrecognised,
+        };
+    }
+
     // Internal to external conversion
     private static byte MoonSixFretToBChart(GHLiveGuitarFret note)
     {

diff --git a/BChartWriter.cs b/BChartWriter.cs
@@ -247,7 +247,7 @@ public static void WriteInstrument(Stream stream, Instrument inst, Dictionary<Di
     {
         void WriteData(Stream stre)
         {
-            stre.WriteUInt32LE(BChartUtils.MoonInstrumentToBChart(inst));
+            stre.WriteByte(BChartUtils.MoonInstrumentToBChart(inst));
             stre.WriteByte((byte)diffs.Count);
             // TODO per instrument events track?
         }

diff --git a/chartFormat.txt b/chartFormat.txt
@@ -61,16 +61,16 @@ bchart format:
     Instrument:
         uint32/byte[4] - INST 0x54534E49 / 0x49 0x4E 0x53 0x54
         int32 - byteLength
-        uint32 instrumentID
-        byte diffCount
+        byte - instrumentID
+        byte - diffCount
         InstrumentDiffEvents
 
         InstrumentDiffEvents: - Required to come after an instrument chunk
             uint32/byte[4] - DIFF 0x46464944 / 0x44 0x49 0x46 0x46
             int32 - byteLength
+            byte - difficultyID
             int32 - eventCount
             [deltaTickEncoding tickPos] [uint32 eventByteLength] [event data]
-            [uint32 tickPos] [uint32 eventByteLength] [event data]
 
         AnimationEvents: Not yet fully defined but reserved for future use! - Required to come after an instrument chunk
             uint32/byte[4] - ANIM