package ibxm;
import java.io.*;
public class FastTracker2 {
public static boolean is_xm( byte[] header_60_bytes ) {
String xm_identifier;
xm_identifier = ascii_text( header_60_bytes, 0, 17 );
return xm_identifier.equals( "Extended Module: " );
}
public static Module load_xm( byte[] header_60_bytes, DataInput data_input ) throws IOException {
int xm_version, song_header_length, sequence_length;
int num_channels, num_patterns, num_instruments, xm_flags, idx;
byte[] structure_header, song_header;
boolean delta_env;
String tracker_name;
Instrument instrument;
Module module;
if( !is_xm( header_60_bytes ) ) {
throw new IllegalArgumentException( "Not an XM file!" );
}
xm_version = unsigned_short_le( header_60_bytes, 58 );
if( xm_version != 0x0104 ) {
throw new IllegalArgumentException( "Sorry, XM version " + xm_version + " is not supported!" );
}
module = new Module();
module.song_title = ascii_text( header_60_bytes, 17, 20 );
tracker_name = ascii_text( header_60_bytes, 38, 20 );
delta_env = tracker_name.startsWith( "DigiBooster Pro" );
structure_header = new byte[ 4 ];
data_input.readFully( structure_header );
song_header_length = int_le( structure_header, 0 );
song_header = new byte[ song_header_length ];
data_input.readFully( song_header, 4, song_header_length - 4 );
sequence_length = unsigned_short_le( song_header, 4 );
module.restart_sequence_index = unsigned_short_le( song_header, 6 );
num_channels = unsigned_short_le( song_header, 8 );
num_patterns = unsigned_short_le( song_header, 10 );
num_instruments = unsigned_short_le( song_header, 12 );
xm_flags = unsigned_short_le( song_header, 14 );
module.linear_periods = ( xm_flags & 0x1 ) == 0x1;
module.global_volume = 64;
module.channel_gain = IBXM.FP_ONE * 3 / 8;
module.default_speed = unsigned_short_le( song_header, 16 );
module.default_tempo = unsigned_short_le( song_header, 18 );
module.set_num_channels( num_channels );
for( idx = 0; idx < num_channels; idx++ ) {
module.set_initial_panning( idx, 128 );
}
module.set_sequence_length( sequence_length );
for( idx = 0; idx < sequence_length; idx++ ) {
module.set_sequence( idx, song_header[ 20 + idx ] & 0xFF );
}
module.set_num_patterns( num_patterns );
for( idx = 0; idx < num_patterns; idx++ ) {
module.set_pattern( idx, read_xm_pattern( data_input, num_channels ) );
}
module.set_num_instruments( num_instruments );
for( idx = 1; idx <= num_instruments; idx++ ) {
try {
instrument = read_xm_instrument( data_input, delta_env );
module.set_instrument( idx, instrument );
} catch( EOFException e ) {
System.out.println( "Instrument " + idx + " is missing!" );
}
}
return module;
}
private static Pattern read_xm_pattern( DataInput data_input, int num_channels ) throws IOException {
int pattern_header_length, packing_type, num_rows, pattern_data_length;
byte[] structure_header, pattern_header, pattern_data;
Pattern pattern;
structure_header = new byte[ 4 ];
data_input.readFully( structure_header );
pattern_header_length = int_le( structure_header, 0 );
pattern_header = new byte[ pattern_header_length ];
data_input.readFully( pattern_header, 4, pattern_header_length - 4 );
packing_type = pattern_header[ 4 ];
if( packing_type != 0 ) {
throw new IllegalArgumentException( "Pattern packing type " + packing_type + " is not supported!" );
}
pattern = new Pattern();
pattern.num_rows = unsigned_short_le( pattern_header, 5 );
pattern_data_length = unsigned_short_le( pattern_header, 7 );
pattern_data = new byte[ pattern_data_length ];
data_input.readFully( pattern_data );
pattern.set_pattern_data( pattern_data );
return pattern;
}
private static Instrument read_xm_instrument( DataInput data_input, boolean delta_env ) throws IOException {
int instrument_header_length, num_samples, idx;
int env_tick, env_ampl, env_num_points, flags;
byte[] structure_header, instrument_header, sample_headers;
Instrument instrument;
Envelope envelope;
structure_header = new byte[ 4 ];
data_input.readFully( structure_header );
instrument_header_length = int_le( structure_header, 0 );
instrument_header = new byte[ instrument_header_length ];
data_input.readFully( instrument_header, 4, instrument_header_length - 4 );
instrument = new Instrument();
instrument.name = ascii_text( instrument_header, 4, 22 );
num_samples = unsigned_short_le( instrument_header, 27 );
if( num_samples > 0 ) {
instrument.set_num_samples( num_samples );
for( idx = 0; idx < 96; idx++ ) {
instrument.set_key_to_sample( idx + 1, instrument_header[ 33 + idx ] & 0xFF );
}
envelope = new Envelope();
env_num_points = instrument_header[ 225 ] & 0xFF;
envelope.set_num_points( env_num_points );
for( idx = 0; idx < env_num_points; idx++ ) {
env_tick = unsigned_short_le( instrument_header, 129 + idx * 4 );
env_ampl = unsigned_short_le( instrument_header, 131 + idx * 4 );
envelope.set_point( idx, env_tick, env_ampl, delta_env );
}
envelope.set_sustain_point( instrument_header[ 227 ] & 0xFF );
envelope.set_loop_points( instrument_header[ 228 ] & 0xFF, instrument_header[ 229 ] & 0xFF );
flags = instrument_header[ 233 ] & 0xFF;
instrument.volume_envelope_active = ( flags & 0x1 ) == 0x1;
envelope.sustain = ( flags & 0x2 ) == 0x2;
envelope.looped = ( flags & 0x4 ) == 0x4;
instrument.set_volume_envelope( envelope );
envelope = new Envelope();
env_num_points = instrument_header[ 226 ] & 0xFF;
envelope.set_num_points( env_num_points );
for( idx = 0; idx < env_num_points; idx++ ) {
env_tick = unsigned_short_le( instrument_header, 177 + idx * 4 );
env_ampl = unsigned_short_le( instrument_header, 179 + idx * 4 );
envelope.set_point( idx, env_tick, env_ampl, delta_env );
}
envelope.set_sustain_point( instrument_header[ 230 ] & 0xFF );
envelope.set_loop_points( instrument_header[ 231 ] & 0xFF, instrument_header[ 232 ] & 0xFF );
flags = instrument_header[ 234 ] & 0xFF;
instrument.panning_envelope_active = ( flags & 0x1 ) == 0x1;
envelope.sustain = ( flags & 0x2 ) == 0x2;
envelope.looped = ( flags & 0x4 ) == 0x4;
instrument.set_panning_envelope( envelope );
instrument.vibrato_type = instrument_header[ 235 ] & 0xFF;
instrument.vibrato_sweep = instrument_header[ 236 ] & 0xFF;
instrument.vibrato_depth = instrument_header[ 237 ] & 0xFF;
instrument.vibrato_rate = instrument_header[ 238 ] & 0xFF;
instrument.volume_fade_out = unsigned_short_le( instrument_header, 239 );
sample_headers = new byte[ num_samples * 40 ];
data_input.readFully( sample_headers );
for( idx = 0; idx < num_samples; idx++ ) {
instrument.set_sample( idx, read_xm_sample( sample_headers, idx, data_input ) );
}
}
return instrument;
}
private static Sample read_xm_sample( byte[] sample_headers, int sample_idx, DataInput data_input ) throws IOException {
int header_offset, sample_length, loop_start, loop_length;
int flags, in_idx, out_idx, sam, last_sam;
int fine_tune, relative_note;
boolean sixteen_bit, ping_pong;
byte[] raw_sample_data;
short[] decoded_sample_data;
Sample sample;
header_offset = sample_idx * 40;
sample = new Sample();
sample_length = int_le( sample_headers, header_offset );
loop_start = int_le( sample_headers, header_offset + 4 );
loop_length = int_le( sample_headers, header_offset + 8 );
sample.volume = sample_headers[ header_offset + 12 ] & 0xFF;
fine_tune = sample_headers[ header_offset + 13 ];
fine_tune = ( fine_tune << IBXM.FP_SHIFT ) / 1536;
sample.set_panning = true;
flags = sample_headers[ header_offset + 14 ] & 0xFF;
if( ( flags & 0x03 ) == 0 ) {
loop_length = 0;
}
ping_pong = ( flags & 0x02 ) == 0x02;
sixteen_bit = ( flags & 0x10 ) == 0x10;
sample.panning = sample_headers[ header_offset + 15 ] & 0xFF;
relative_note = sample_headers[ header_offset + 16 ];
relative_note = ( relative_note << IBXM.FP_SHIFT ) / 12;
sample.transpose = relative_note + fine_tune;
sample.name = ascii_text( sample_headers, header_offset + 18, 22 );
raw_sample_data = new byte[ sample_length ];
try {
data_input.readFully( raw_sample_data );
} catch( EOFException e ) {
System.out.println( "Sample has been truncated!" );
}
in_idx = 0;
out_idx = 0;
sam = 0;
last_sam = 0;
if( sixteen_bit ) {
decoded_sample_data = new short[ sample_length >> 1 ];
while( in_idx < raw_sample_data.length ) {
sam = raw_sample_data[ in_idx ] & 0xFF;
sam = sam | ( ( raw_sample_data[ in_idx + 1 ] & 0xFF ) << 8 );
last_sam = last_sam + sam;
decoded_sample_data[ out_idx ] = ( short ) last_sam;
in_idx += 2;
out_idx += 1;
}
sample.set_sample_data( decoded_sample_data, loop_start >> 1, loop_length >> 1, ping_pong );
} else {
decoded_sample_data = new short[ sample_length ];
while( in_idx < raw_sample_data.length ) {
sam = raw_sample_data[ in_idx ] & 0xFF;
last_sam = last_sam + sam;
decoded_sample_data[ out_idx ] = ( short ) ( last_sam << 8 );
in_idx += 1;
out_idx += 1;
}
sample.set_sample_data( decoded_sample_data, loop_start, loop_length, ping_pong );
}
return sample;
}
private static int unsigned_short_le( byte[] buffer, int offset ) {
int value;
value = buffer[ offset ] & 0xFF;
value = value | ( ( buffer[ offset + 1 ] & 0xFF ) << 8 );
return value;
}
private static int int_le( byte[] buffer, int offset ) {
int value;
value = buffer[ offset ] & 0xFF;
value = value | ( ( buffer[ offset + 1 ] & 0xFF ) << 8 );
value = value | ( ( buffer[ offset + 2 ] & 0xFF ) << 16 );
value = value | ( ( buffer[ offset + 3 ] & 0x7F ) << 24 );
return value;
}
private static String ascii_text( byte[] buffer, int offset, int length ) {
int idx, chr;
byte[] string_buffer;
String string;
string_buffer = new byte[ length ];
for( idx = 0; idx < length; idx++ ) {
chr = buffer[ offset + idx ];
if( chr < 32 ) {
chr = 32;
}
string_buffer[ idx ] = ( byte ) chr;
}
try {
string = new String( string_buffer, 0, length, "ISO-8859-1" );
} catch( UnsupportedEncodingException e ) {
string = "";
}
return string;
}
}