diff options
Diffstat (limited to 'plugins/gme/game-music-emu-svn/gme/Nes_Vrc6_Apu.cpp')
| -rw-r--r-- | plugins/gme/game-music-emu-svn/gme/Nes_Vrc6_Apu.cpp | 215 |
1 files changed, 0 insertions, 215 deletions
diff --git a/plugins/gme/game-music-emu-svn/gme/Nes_Vrc6_Apu.cpp b/plugins/gme/game-music-emu-svn/gme/Nes_Vrc6_Apu.cpp deleted file mode 100644 index d178407c..00000000 --- a/plugins/gme/game-music-emu-svn/gme/Nes_Vrc6_Apu.cpp +++ /dev/null @@ -1,215 +0,0 @@ -// Nes_Snd_Emu 0.1.8. http://www.slack.net/~ant/ - -#include "Nes_Vrc6_Apu.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" - -Nes_Vrc6_Apu::Nes_Vrc6_Apu() -{ - output( NULL ); - volume( 1.0 ); - reset(); -} - -void Nes_Vrc6_Apu::reset() -{ - last_time = 0; - for ( int i = 0; i < osc_count; i++ ) - { - Vrc6_Osc& osc = oscs [i]; - for ( int j = 0; j < reg_count; j++ ) - osc.regs [j] = 0; - osc.delay = 0; - osc.last_amp = 0; - osc.phase = 1; - osc.amp = 0; - } -} - -void Nes_Vrc6_Apu::output( Blip_Buffer* buf ) -{ - for ( int i = 0; i < osc_count; i++ ) - osc_output( i, buf ); -} - -void Nes_Vrc6_Apu::run_until( blip_time_t time ) -{ - require( time >= last_time ); - run_square( oscs [0], time ); - run_square( oscs [1], time ); - run_saw( time ); - last_time = time; -} - -void Nes_Vrc6_Apu::write_osc( blip_time_t time, int osc_index, int reg, int data ) -{ - require( (unsigned) osc_index < osc_count ); - require( (unsigned) reg < reg_count ); - - run_until( time ); - oscs [osc_index].regs [reg] = data; -} - -void Nes_Vrc6_Apu::end_frame( blip_time_t time ) -{ - if ( time > last_time ) - run_until( time ); - - assert( last_time >= time ); - last_time -= time; -} - -void Nes_Vrc6_Apu::save_state( vrc6_apu_state_t* out ) const -{ - assert( sizeof (vrc6_apu_state_t) == 20 ); - out->saw_amp = oscs [2].amp; - for ( int i = 0; i < osc_count; i++ ) - { - Vrc6_Osc const& osc = oscs [i]; - for ( int r = 0; r < reg_count; r++ ) - out->regs [i] [r] = osc.regs [r]; - - out->delays [i] = osc.delay; - out->phases [i] = osc.phase; - } -} - -void Nes_Vrc6_Apu::load_state( vrc6_apu_state_t const& in ) -{ - reset(); - oscs [2].amp = in.saw_amp; - for ( int i = 0; i < osc_count; i++ ) - { - Vrc6_Osc& osc = oscs [i]; - for ( int r = 0; r < reg_count; r++ ) - osc.regs [r] = in.regs [i] [r]; - - osc.delay = in.delays [i]; - osc.phase = in.phases [i]; - } - if ( !oscs [2].phase ) - oscs [2].phase = 1; -} - -void Nes_Vrc6_Apu::run_square( Vrc6_Osc& osc, blip_time_t end_time ) -{ - Blip_Buffer* output = osc.output; - if ( !output ) - return; - output->set_modified(); - - int volume = osc.regs [0] & 15; - if ( !(osc.regs [2] & 0x80) ) - volume = 0; - - int gate = osc.regs [0] & 0x80; - int duty = ((osc.regs [0] >> 4) & 7) + 1; - int delta = ((gate || osc.phase < duty) ? volume : 0) - osc.last_amp; - blip_time_t time = last_time; - if ( delta ) - { - osc.last_amp += delta; - square_synth.offset( time, delta, output ); - } - - time += osc.delay; - osc.delay = 0; - int period = osc.period(); - if ( volume && !gate && period > 4 ) - { - if ( time < end_time ) - { - int phase = osc.phase; - - do - { - phase++; - if ( phase == 16 ) - { - phase = 0; - osc.last_amp = volume; - square_synth.offset( time, volume, output ); - } - if ( phase == duty ) - { - osc.last_amp = 0; - square_synth.offset( time, -volume, output ); - } - time += period; - } - while ( time < end_time ); - - osc.phase = phase; - } - osc.delay = time - end_time; - } -} - -void Nes_Vrc6_Apu::run_saw( blip_time_t end_time ) -{ - Vrc6_Osc& osc = oscs [2]; - Blip_Buffer* output = osc.output; - if ( !output ) - return; - output->set_modified(); - - int amp = osc.amp; - int amp_step = osc.regs [0] & 0x3F; - blip_time_t time = last_time; - int last_amp = osc.last_amp; - if ( !(osc.regs [2] & 0x80) || !(amp_step | amp) ) - { - osc.delay = 0; - int delta = (amp >> 3) - last_amp; - last_amp = amp >> 3; - saw_synth.offset( time, delta, output ); - } - else - { - time += osc.delay; - if ( time < end_time ) - { - int period = osc.period() * 2; - int phase = osc.phase; - - do - { - if ( --phase == 0 ) - { - phase = 7; - amp = 0; - } - - int delta = (amp >> 3) - last_amp; - if ( delta ) - { - last_amp = amp >> 3; - saw_synth.offset( time, delta, output ); - } - - time += period; - amp = (amp + amp_step) & 0xFF; - } - while ( time < end_time ); - - osc.phase = phase; - osc.amp = amp; - } - - osc.delay = time - end_time; - } - - osc.last_amp = last_amp; -} - |