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Diffstat (limited to 'plugins/gme/game-music-emu-0.6.0/gme/Nes_Apu.cpp')
-rw-r--r--plugins/gme/game-music-emu-0.6.0/gme/Nes_Apu.cpp391
1 files changed, 0 insertions, 391 deletions
diff --git a/plugins/gme/game-music-emu-0.6.0/gme/Nes_Apu.cpp b/plugins/gme/game-music-emu-0.6.0/gme/Nes_Apu.cpp
deleted file mode 100644
index 68edb446..00000000
--- a/plugins/gme/game-music-emu-0.6.0/gme/Nes_Apu.cpp
+++ /dev/null
@@ -1,391 +0,0 @@
-// Nes_Snd_Emu 0.1.8. http://www.slack.net/~ant/
-
-#include "Nes_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"
-
-int const amp_range = 15;
-
-Nes_Apu::Nes_Apu() :
- square1( &square_synth ),
- square2( &square_synth )
-{
- tempo_ = 1.0;
- dmc.apu = this;
- dmc.prg_reader = NULL;
- irq_notifier_ = NULL;
-
- oscs [0] = &square1;
- oscs [1] = &square2;
- oscs [2] = ▵
- oscs [3] = &noise;
- oscs [4] = &dmc;
-
- output( NULL );
- volume( 1.0 );
- reset( false );
-}
-
-void Nes_Apu::treble_eq( const blip_eq_t& eq )
-{
- square_synth.treble_eq( eq );
- triangle.synth.treble_eq( eq );
- noise.synth.treble_eq( eq );
- dmc.synth.treble_eq( eq );
-}
-
-void Nes_Apu::enable_nonlinear( double v )
-{
- dmc.nonlinear = true;
- square_synth.volume( 1.3 * 0.25751258 / 0.742467605 * 0.25 / amp_range * v );
-
- const double tnd = 0.48 / 202 * nonlinear_tnd_gain();
- triangle.synth.volume( 3.0 * tnd );
- noise.synth.volume( 2.0 * tnd );
- dmc.synth.volume( tnd );
-
- square1 .last_amp = 0;
- square2 .last_amp = 0;
- triangle.last_amp = 0;
- noise .last_amp = 0;
- dmc .last_amp = 0;
-}
-
-void Nes_Apu::volume( double v )
-{
- dmc.nonlinear = false;
- square_synth.volume( 0.1128 / amp_range * v );
- triangle.synth.volume( 0.12765 / amp_range * v );
- noise.synth.volume( 0.0741 / amp_range * v );
- dmc.synth.volume( 0.42545 / 127 * v );
-}
-
-void Nes_Apu::output( Blip_Buffer* buffer )
-{
- for ( int i = 0; i < osc_count; i++ )
- osc_output( i, buffer );
-}
-
-void Nes_Apu::set_tempo( double t )
-{
- tempo_ = t;
- frame_period = (dmc.pal_mode ? 8314 : 7458);
- if ( t != 1.0 )
- frame_period = (int) (frame_period / t) & ~1; // must be even
-}
-
-void Nes_Apu::reset( bool pal_mode, int initial_dmc_dac )
-{
- dmc.pal_mode = pal_mode;
- set_tempo( tempo_ );
-
- square1.reset();
- square2.reset();
- triangle.reset();
- noise.reset();
- dmc.reset();
-
- last_time = 0;
- last_dmc_time = 0;
- osc_enables = 0;
- irq_flag = false;
- earliest_irq_ = no_irq;
- frame_delay = 1;
- write_register( 0, 0x4017, 0x00 );
- write_register( 0, 0x4015, 0x00 );
-
- for ( nes_addr_t addr = start_addr; addr <= 0x4013; addr++ )
- write_register( 0, addr, (addr & 3) ? 0x00 : 0x10 );
-
- dmc.dac = initial_dmc_dac;
- if ( !dmc.nonlinear )
- triangle.last_amp = 15;
- if ( !dmc.nonlinear ) // TODO: remove?
- dmc.last_amp = initial_dmc_dac; // prevent output transition
-}
-
-void Nes_Apu::irq_changed()
-{
- nes_time_t new_irq = dmc.next_irq;
- if ( dmc.irq_flag | irq_flag ) {
- new_irq = 0;
- }
- else if ( new_irq > next_irq ) {
- new_irq = next_irq;
- }
-
- if ( new_irq != earliest_irq_ ) {
- earliest_irq_ = new_irq;
- if ( irq_notifier_ )
- irq_notifier_( irq_data );
- }
-}
-
-// frames
-
-void Nes_Apu::run_until( nes_time_t end_time )
-{
- require( end_time >= last_dmc_time );
- if ( end_time > next_dmc_read_time() )
- {
- nes_time_t start = last_dmc_time;
- last_dmc_time = end_time;
- dmc.run( start, end_time );
- }
-}
-
-void Nes_Apu::run_until_( nes_time_t end_time )
-{
- require( end_time >= last_time );
-
- if ( end_time == last_time )
- return;
-
- if ( last_dmc_time < end_time )
- {
- nes_time_t start = last_dmc_time;
- last_dmc_time = end_time;
- dmc.run( start, end_time );
- }
-
- while ( true )
- {
- // earlier of next frame time or end time
- nes_time_t time = last_time + frame_delay;
- if ( time > end_time )
- time = end_time;
- frame_delay -= time - last_time;
-
- // run oscs to present
- square1.run( last_time, time );
- square2.run( last_time, time );
- triangle.run( last_time, time );
- noise.run( last_time, time );
- last_time = time;
-
- if ( time == end_time )
- break; // no more frames to run
-
- // take frame-specific actions
- frame_delay = frame_period;
- switch ( frame++ )
- {
- case 0:
- if ( !(frame_mode & 0xC0) ) {
- next_irq = time + frame_period * 4 + 2;
- irq_flag = true;
- }
- // fall through
- case 2:
- // clock length and sweep on frames 0 and 2
- square1.clock_length( 0x20 );
- square2.clock_length( 0x20 );
- noise.clock_length( 0x20 );
- triangle.clock_length( 0x80 ); // different bit for halt flag on triangle
-
- square1.clock_sweep( -1 );
- square2.clock_sweep( 0 );
-
- // frame 2 is slightly shorter in mode 1
- if ( dmc.pal_mode && frame == 3 )
- frame_delay -= 2;
- break;
-
- case 1:
- // frame 1 is slightly shorter in mode 0
- if ( !dmc.pal_mode )
- frame_delay -= 2;
- break;
-
- case 3:
- frame = 0;
-
- // frame 3 is almost twice as long in mode 1
- if ( frame_mode & 0x80 )
- frame_delay += frame_period - (dmc.pal_mode ? 2 : 6);
- break;
- }
-
- // clock envelopes and linear counter every frame
- triangle.clock_linear_counter();
- square1.clock_envelope();
- square2.clock_envelope();
- noise.clock_envelope();
- }
-}
-
-template<class T>
-inline void zero_apu_osc( T* osc, nes_time_t time )
-{
- Blip_Buffer* output = osc->output;
- int last_amp = osc->last_amp;
- osc->last_amp = 0;
- if ( output && last_amp )
- osc->synth.offset( time, -last_amp, output );
-}
-
-void Nes_Apu::end_frame( nes_time_t end_time )
-{
- if ( end_time > last_time )
- run_until_( end_time );
-
- if ( dmc.nonlinear )
- {
- zero_apu_osc( &square1, last_time );
- zero_apu_osc( &square2, last_time );
- zero_apu_osc( &triangle, last_time );
- zero_apu_osc( &noise, last_time );
- zero_apu_osc( &dmc, last_time );
- }
-
- // make times relative to new frame
- last_time -= end_time;
- require( last_time >= 0 );
-
- last_dmc_time -= end_time;
- require( last_dmc_time >= 0 );
-
- if ( next_irq != no_irq ) {
- next_irq -= end_time;
- check( next_irq >= 0 );
- }
- if ( dmc.next_irq != no_irq ) {
- dmc.next_irq -= end_time;
- check( dmc.next_irq >= 0 );
- }
- if ( earliest_irq_ != no_irq ) {
- earliest_irq_ -= end_time;
- if ( earliest_irq_ < 0 )
- earliest_irq_ = 0;
- }
-}
-
-// registers
-
-static const unsigned char length_table [0x20] = {
- 0x0A, 0xFE, 0x14, 0x02, 0x28, 0x04, 0x50, 0x06,
- 0xA0, 0x08, 0x3C, 0x0A, 0x0E, 0x0C, 0x1A, 0x0E,
- 0x0C, 0x10, 0x18, 0x12, 0x30, 0x14, 0x60, 0x16,
- 0xC0, 0x18, 0x48, 0x1A, 0x10, 0x1C, 0x20, 0x1E
-};
-
-void Nes_Apu::write_register( nes_time_t time, nes_addr_t addr, int data )
-{
- require( addr > 0x20 ); // addr must be actual address (i.e. 0x40xx)
- require( (unsigned) data <= 0xFF );
-
- // Ignore addresses outside range
- if ( unsigned (addr - start_addr) > end_addr - start_addr )
- return;
-
- run_until_( time );
-
- if ( addr < 0x4014 )
- {
- // Write to channel
- int osc_index = (addr - start_addr) >> 2;
- Nes_Osc* osc = oscs [osc_index];
-
- int reg = addr & 3;
- osc->regs [reg] = data;
- osc->reg_written [reg] = true;
-
- if ( osc_index == 4 )
- {
- // handle DMC specially
- dmc.write_register( reg, data );
- }
- else if ( reg == 3 )
- {
- // load length counter
- if ( (osc_enables >> osc_index) & 1 )
- osc->length_counter = length_table [(data >> 3) & 0x1F];
-
- // reset square phase
- if ( osc_index < 2 )
- ((Nes_Square*) osc)->phase = Nes_Square::phase_range - 1;
- }
- }
- else if ( addr == 0x4015 )
- {
- // Channel enables
- for ( int i = osc_count; i--; )
- if ( !((data >> i) & 1) )
- oscs [i]->length_counter = 0;
-
- bool recalc_irq = dmc.irq_flag;
- dmc.irq_flag = false;
-
- int old_enables = osc_enables;
- osc_enables = data;
- if ( !(data & 0x10) ) {
- dmc.next_irq = no_irq;
- recalc_irq = true;
- }
- else if ( !(old_enables & 0x10) ) {
- dmc.start(); // dmc just enabled
- }
-
- if ( recalc_irq )
- irq_changed();
- }
- else if ( addr == 0x4017 )
- {
- // Frame mode
- frame_mode = data;
-
- bool irq_enabled = !(data & 0x40);
- irq_flag &= irq_enabled;
- next_irq = no_irq;
-
- // mode 1
- frame_delay = (frame_delay & 1);
- frame = 0;
-
- if ( !(data & 0x80) )
- {
- // mode 0
- frame = 1;
- frame_delay += frame_period;
- if ( irq_enabled )
- next_irq = time + frame_delay + frame_period * 3 + 1;
- }
-
- irq_changed();
- }
-}
-
-int Nes_Apu::read_status( nes_time_t time )
-{
- run_until_( time - 1 );
-
- int result = (dmc.irq_flag << 7) | (irq_flag << 6);
-
- for ( int i = 0; i < osc_count; i++ )
- if ( oscs [i]->length_counter )
- result |= 1 << i;
-
- run_until_( time );
-
- if ( irq_flag )
- {
- result |= 0x40;
- irq_flag = false;
- irq_changed();
- }
-
- //debug_printf( "%6d/%d Read $4015->$%02X\n", frame_delay, frame, result );
-
- return result;
-}
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