1 --------------------------------------------------------------------------
    2                           XI format description
    3                    (FastTracker II Extended Instrument)
    4           reverse engineered by KB / The Obsessed Maniacs / Reflex
    5 --------------------------------------------------------------------------
    6 C = Chars, B = Byte, W = Word, D = Double word
    7 
    8 Pos(h) Len(h) Meaning
    9 -------------------------------------------------------------- file header
   10 0000   C15    "Extended Instrument: "
   11 0015   C16    Instrument name, padded w/ spaces
   12 
   13 002b   B01    $1a
   14 002c   C14    Tracker name, padded w/ spaces
   15 0040   W02    Version Number (current $0102)
   16 
   17 -------------------------------------------------------------- inst header
   18 0042   B60    Sample number for notes 1..96
   19 
   20 00a2   W30    12 volume envelope points:
   21               +0 Time index for Point 1 (ticks since note)
   22               +2 Volume for Point 1     (00..40)
   23               +4 Time index for Point 2
   24               +6 Volume for Point 2
   25               [...]
   26 00d2   W30    12 panning envelope points
   27               (Same structure as volume envelope)
   28 
   29 0102   B01    Number of volume points
   30 0103   B01    Number of panning points
   31 0104   B01    Volume sustain point
   32 0105   B01    Volume loop start point
   33 0106   B01    Volume loop end point
   34 0107   B01    Panning sustain point
   35 0108   B01    Panning loop start point
   36 0109   B01    Panning loop end point
   37 010a   B01    Volume type;   b0=on, b1=sustain, b2=loop
   38 010b   B01    Panning type;  b0=on, b1=sustain, b2=loop
   39 
   40 010c   B01    Vibrato type
   41 010d   B01    Vibrato sweep
   42 010e   B01    Vibrato depth
   43 010f   B01    Vibrato rate
   44 
   45 0110   W02    Volume fadeout (0..fff)
   46 0112   B16    ????? (Zeroes)
   47 
   48 0128   W02    Number of Samples
   49 
   50 ---------------------------------------------------------- sample headers
   51 
   52 012a   D04    Sample Length
   53 012e   D04    Sample loop start
   54 0132   D04    Sample loop length
   55 0136   B01    Volume
   56 0137   B01    Finetune (signed)
   57 0138   B01    Sample Type; b0,1=loop: 0=none 1=fwd 2=bidi
   58                            b4=16bit sample
   59 0139   B01    Panning
   60 0140   B01    Relative Note (signed, 00=C-4) (call it Transpose)
   61 0141   B01    Sample Name Length
   62 0142   C16    Sample Name, padded w/ zeroes
   63 
   64 And so on w/ samples 1 to x
   65 Length: $28 bytes for each sample
   66 
   67 ------------------------------------------------------------- sample data
   68 
   69 $012a+(number of samples)*$28 : sample data for all samples in delta values
   70                                 (signed)
   71