From 55cba1db948c3d6650a0d4162ffcd09ca73fe3a1 Mon Sep 17 00:00:00 2001 From: waker Date: Mon, 6 Jul 2009 22:43:23 +0200 Subject: added GME support ; added subtune support --- gme/Vgm_Emu_Impl.cpp | 314 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 314 insertions(+) create mode 100644 gme/Vgm_Emu_Impl.cpp (limited to 'gme/Vgm_Emu_Impl.cpp') diff --git a/gme/Vgm_Emu_Impl.cpp b/gme/Vgm_Emu_Impl.cpp new file mode 100644 index 00000000..a2d7c93e --- /dev/null +++ b/gme/Vgm_Emu_Impl.cpp @@ -0,0 +1,314 @@ +// Game_Music_Emu 0.5.2. http://www.slack.net/~ant/ + +#include "Vgm_Emu.h" + +#include +#include +#include "blargg_endian.h" + +/* Copyright (C) 2003-2006 Shay Green. This module is free software; you +can redistribute it and/or modify it under the terms of the GNU Lesser +General Public License as published by the Free Software Foundation; either +version 2.1 of the License, or (at your option) any later version. This +module is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS +FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more +details. You should have received a copy of the GNU Lesser General Public +License along with this module; if not, write to the Free Software Foundation, +Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ + +#include "blargg_source.h" + +enum { + cmd_gg_stereo = 0x4F, + cmd_psg = 0x50, + cmd_ym2413 = 0x51, + cmd_ym2612_port0 = 0x52, + cmd_ym2612_port1 = 0x53, + cmd_ym2151 = 0x54, + cmd_delay = 0x61, + cmd_delay_735 = 0x62, + cmd_delay_882 = 0x63, + cmd_byte_delay = 0x64, + cmd_end = 0x66, + cmd_data_block = 0x67, + cmd_short_delay = 0x70, + cmd_pcm_delay = 0x80, + cmd_pcm_seek = 0xE0, + + pcm_block_type = 0x00, + ym2612_dac_port = 0x2A +}; + +inline int command_len( int command ) +{ + switch ( command >> 4 ) + { + case 0x03: + case 0x04: + return 2; + + case 0x05: + case 0x0A: + case 0x0B: + return 3; + + case 0x0C: + case 0x0D: + return 4; + + case 0x0E: + case 0x0F: + return 5; + } + + check( false ); + return 1; +} + +template +inline void Ym_Emu::begin_frame( short* p ) +{ + require( enabled() ); + out = p; + last_time = 0; +} + +template +inline int Ym_Emu::run_until( int time ) +{ + int count = time - last_time; + if ( count > 0 ) + { + if ( last_time < 0 ) + return false; + last_time = time; + short* p = out; + out += count * Emu::out_chan_count; + Emu::run( count, p ); + } + return true; +} + +inline Vgm_Emu_Impl::fm_time_t Vgm_Emu_Impl::to_fm_time( vgm_time_t t ) const +{ + return (t * fm_time_factor + fm_time_offset) >> fm_time_bits; +} + +inline blip_time_t Vgm_Emu_Impl::to_blip_time( vgm_time_t t ) const +{ + return (t * blip_time_factor) >> blip_time_bits; +} + +void Vgm_Emu_Impl::write_pcm( vgm_time_t vgm_time, int amp ) +{ + blip_time_t blip_time = to_blip_time( vgm_time ); + int old = dac_amp; + int delta = amp - old; + dac_amp = amp; + if ( old >= 0 ) + dac_synth.offset_inline( blip_time, delta, &blip_buf ); + else + dac_amp |= dac_disabled; +} + +blip_time_t Vgm_Emu_Impl::run_commands( vgm_time_t end_time ) +{ + vgm_time_t vgm_time = this->vgm_time; + byte const* pos = this->pos; + if ( pos >= data_end ) + { + set_track_ended(); + if ( pos > data_end ) + set_warning( "Stream lacked end event" ); + } + + while ( vgm_time < end_time && pos < data_end ) + { + // TODO: be sure there are enough bytes left in stream for particular command + // so we don't read past end + switch ( *pos++ ) + { + case cmd_end: + pos = loop_begin; // if not looped, loop_begin == data_end + break; + + case cmd_delay_735: + vgm_time += 735; + break; + + case cmd_delay_882: + vgm_time += 882; + break; + + case cmd_gg_stereo: + psg.write_ggstereo( to_blip_time( vgm_time ), *pos++ ); + break; + + case cmd_psg: + psg.write_data( to_blip_time( vgm_time ), *pos++ ); + break; + + case cmd_delay: + vgm_time += pos [1] * 0x100L + pos [0]; + pos += 2; + break; + + case cmd_byte_delay: + vgm_time += *pos++; + break; + + case cmd_ym2413: + if ( ym2413.run_until( to_fm_time( vgm_time ) ) ) + ym2413.write( pos [0], pos [1] ); + pos += 2; + break; + + case cmd_ym2612_port0: + if ( pos [0] == ym2612_dac_port ) + { + write_pcm( vgm_time, pos [1] ); + } + else if ( ym2612.run_until( to_fm_time( vgm_time ) ) ) + { + if ( pos [0] == 0x2B ) + { + dac_disabled = (pos [1] >> 7 & 1) - 1; + dac_amp |= dac_disabled; + } + ym2612.write0( pos [0], pos [1] ); + } + pos += 2; + break; + + case cmd_ym2612_port1: + if ( ym2612.run_until( to_fm_time( vgm_time ) ) ) + ym2612.write1( pos [0], pos [1] ); + pos += 2; + break; + + case cmd_data_block: { + check( *pos == cmd_end ); + int type = pos [1]; + long size = get_le32( pos + 2 ); + pos += 6; + if ( type == pcm_block_type ) + pcm_data = pos; + pos += size; + break; + } + + case cmd_pcm_seek: + pcm_pos = pcm_data + pos [3] * 0x1000000L + pos [2] * 0x10000L + + pos [1] * 0x100L + pos [0]; + pos += 4; + break; + + default: + int cmd = pos [-1]; + switch ( cmd & 0xF0 ) + { + case cmd_pcm_delay: + write_pcm( vgm_time, *pcm_pos++ ); + vgm_time += cmd & 0x0F; + break; + + case cmd_short_delay: + vgm_time += (cmd & 0x0F) + 1; + break; + + case 0x50: + pos += 2; + break; + + default: + pos += command_len( cmd ) - 1; + set_warning( "Unknown stream event" ); + } + } + } + vgm_time -= end_time; + this->pos = pos; + this->vgm_time = vgm_time; + + return to_blip_time( end_time ); +} + +int Vgm_Emu_Impl::play_frame( blip_time_t blip_time, int sample_count, sample_t* buf ) +{ + // to do: timing is working mostly by luck + + int min_pairs = sample_count >> 1; + int vgm_time = ((long) min_pairs << fm_time_bits) / fm_time_factor - 1; + assert( to_fm_time( vgm_time ) <= min_pairs ); + int pairs = min_pairs; + while ( (pairs = to_fm_time( vgm_time )) < min_pairs ) + vgm_time++; + //dprintf( "pairs: %d, min_pairs: %d\n", pairs, min_pairs ); + + if ( ym2612.enabled() ) + { + ym2612.begin_frame( buf ); + memset( buf, 0, pairs * stereo * sizeof *buf ); + } + else if ( ym2413.enabled() ) + { + ym2413.begin_frame( buf ); + } + + run_commands( vgm_time ); + ym2612.run_until( pairs ); + ym2413.run_until( pairs ); + + fm_time_offset = (vgm_time * fm_time_factor + fm_time_offset) - + ((long) pairs << fm_time_bits); + + psg.end_frame( blip_time ); + + return pairs * stereo; +} + +// Update pre-1.10 header FM rates by scanning commands +void Vgm_Emu_Impl::update_fm_rates( long* ym2413_rate, long* ym2612_rate ) const +{ + byte const* p = data + 0x40; + while ( p < data_end ) + { + switch ( *p ) + { + case cmd_end: + return; + + case cmd_psg: + case cmd_byte_delay: + p += 2; + break; + + case cmd_delay: + p += 3; + break; + + case cmd_data_block: + p += 7 + get_le32( p + 3 ); + break; + + case cmd_ym2413: + *ym2612_rate = 0; + return; + + case cmd_ym2612_port0: + case cmd_ym2612_port1: + *ym2612_rate = *ym2413_rate; + *ym2413_rate = 0; + return; + + case cmd_ym2151: + *ym2413_rate = 0; + *ym2612_rate = 0; + return; + + default: + p += command_len( *p ); + } + } +} -- cgit v1.2.3