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Diffstat (limited to 'plugins/gme/game-music-emu-0.5.5/gme/Nes_Oscs.cpp')
-rw-r--r--plugins/gme/game-music-emu-0.5.5/gme/Nes_Oscs.cpp551
1 files changed, 0 insertions, 551 deletions
diff --git a/plugins/gme/game-music-emu-0.5.5/gme/Nes_Oscs.cpp b/plugins/gme/game-music-emu-0.5.5/gme/Nes_Oscs.cpp
deleted file mode 100644
index 1ad3f59c..00000000
--- a/plugins/gme/game-music-emu-0.5.5/gme/Nes_Oscs.cpp
+++ /dev/null
@@ -1,551 +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"
-
-// Nes_Osc
-
-void Nes_Osc::clock_length( int halt_mask )
-{
- if ( length_counter && !(regs [0] & halt_mask) )
- length_counter--;
-}
-
-void Nes_Envelope::clock_envelope()
-{
- int period = regs [0] & 15;
- if ( reg_written [3] ) {
- reg_written [3] = false;
- env_delay = period;
- envelope = 15;
- }
- else if ( --env_delay < 0 ) {
- env_delay = period;
- if ( envelope | (regs [0] & 0x20) )
- envelope = (envelope - 1) & 15;
- }
-}
-
-int Nes_Envelope::volume() const
-{
- return length_counter == 0 ? 0 : (regs [0] & 0x10) ? (regs [0] & 15) : envelope;
-}
-
-// Nes_Square
-
-void Nes_Square::clock_sweep( int negative_adjust )
-{
- int sweep = regs [1];
-
- if ( --sweep_delay < 0 )
- {
- reg_written [1] = true;
-
- int period = this->period();
- int shift = sweep & shift_mask;
- if ( shift && (sweep & 0x80) && period >= 8 )
- {
- int offset = period >> shift;
-
- if ( sweep & negate_flag )
- offset = negative_adjust - offset;
-
- if ( period + offset < 0x800 )
- {
- period += offset;
- // rewrite period
- regs [2] = period & 0xFF;
- regs [3] = (regs [3] & ~7) | ((period >> 8) & 7);
- }
- }
- }
-
- if ( reg_written [1] ) {
- reg_written [1] = false;
- sweep_delay = (sweep >> 4) & 7;
- }
-}
-
-// TODO: clean up
-inline nes_time_t Nes_Square::maintain_phase( nes_time_t time, nes_time_t end_time,
- nes_time_t timer_period )
-{
- nes_time_t remain = end_time - time;
- if ( remain > 0 )
- {
- int count = (remain + timer_period - 1) / timer_period;
- phase = (phase + count) & (phase_range - 1);
- time += (blargg_long) count * timer_period;
- }
- return time;
-}
-
-void Nes_Square::run( nes_time_t time, nes_time_t end_time )
-{
- const int period = this->period();
- const int timer_period = (period + 1) * 2;
-
- if ( !output )
- {
- delay = maintain_phase( time + delay, end_time, timer_period ) - end_time;
- return;
- }
-
- output->set_modified();
-
- int offset = period >> (regs [1] & shift_mask);
- if ( regs [1] & negate_flag )
- offset = 0;
-
- const int volume = this->volume();
- if ( volume == 0 || period < 8 || (period + offset) >= 0x800 )
- {
- if ( last_amp ) {
- synth.offset( time, -last_amp, output );
- last_amp = 0;
- }
-
- time += delay;
- time = maintain_phase( time, end_time, timer_period );
- }
- else
- {
- // handle duty select
- int duty_select = (regs [0] >> 6) & 3;
- int duty = 1 << duty_select; // 1, 2, 4, 2
- int amp = 0;
- if ( duty_select == 3 ) {
- duty = 2; // negated 25%
- amp = volume;
- }
- if ( phase < duty )
- amp ^= volume;
-
- {
- int delta = update_amp( amp );
- if ( delta )
- synth.offset( time, delta, output );
- }
-
- time += delay;
- if ( time < end_time )
- {
- Blip_Buffer* const output = this->output;
- const Synth& synth = this->synth;
- int delta = amp * 2 - volume;
- int phase = this->phase;
-
- do {
- phase = (phase + 1) & (phase_range - 1);
- if ( phase == 0 || phase == duty ) {
- delta = -delta;
- synth.offset_inline( time, delta, output );
- }
- time += timer_period;
- }
- while ( time < end_time );
-
- last_amp = (delta + volume) >> 1;
- this->phase = phase;
- }
- }
-
- delay = time - end_time;
-}
-
-// Nes_Triangle
-
-void Nes_Triangle::clock_linear_counter()
-{
- if ( reg_written [3] )
- linear_counter = regs [0] & 0x7F;
- else if ( linear_counter )
- linear_counter--;
-
- if ( !(regs [0] & 0x80) )
- reg_written [3] = false;
-}
-
-inline int Nes_Triangle::calc_amp() const
-{
- int amp = phase_range - phase;
- if ( amp < 0 )
- amp = phase - (phase_range + 1);
- return amp;
-}
-
-// TODO: clean up
-inline nes_time_t Nes_Triangle::maintain_phase( nes_time_t time, nes_time_t end_time,
- nes_time_t timer_period )
-{
- nes_time_t remain = end_time - time;
- if ( remain > 0 )
- {
- int count = (remain + timer_period - 1) / timer_period;
- phase = ((unsigned) phase + 1 - count) & (phase_range * 2 - 1);
- phase++;
- time += (blargg_long) count * timer_period;
- }
- return time;
-}
-
-void Nes_Triangle::run( nes_time_t time, nes_time_t end_time )
-{
- const int timer_period = period() + 1;
- if ( !output )
- {
- time += delay;
- delay = 0;
- if ( length_counter && linear_counter && timer_period >= 3 )
- delay = maintain_phase( time, end_time, timer_period ) - end_time;
- return;
- }
-
- output->set_modified();
-
- // to do: track phase when period < 3
- // to do: Output 7.5 on dac when period < 2? More accurate, but results in more clicks.
-
- int delta = update_amp( calc_amp() );
- if ( delta )
- synth.offset( time, delta, output );
-
- time += delay;
- if ( length_counter == 0 || linear_counter == 0 || timer_period < 3 )
- {
- time = end_time;
- }
- else if ( time < end_time )
- {
- Blip_Buffer* const output = this->output;
-
- int phase = this->phase;
- int volume = 1;
- if ( phase > phase_range ) {
- phase -= phase_range;
- volume = -volume;
- }
-
- do {
- if ( --phase == 0 ) {
- phase = phase_range;
- volume = -volume;
- }
- else {
- synth.offset_inline( time, volume, output );
- }
-
- time += timer_period;
- }
- while ( time < end_time );
-
- if ( volume < 0 )
- phase += phase_range;
- this->phase = phase;
- last_amp = calc_amp();
- }
- delay = time - end_time;
-}
-
-// Nes_Dmc
-
-void Nes_Dmc::reset()
-{
- address = 0;
- dac = 0;
- buf = 0;
- bits_remain = 1;
- bits = 0;
- buf_full = false;
- silence = true;
- next_irq = Nes_Apu::no_irq;
- irq_flag = false;
- irq_enabled = false;
-
- Nes_Osc::reset();
- period = 0x1AC;
-}
-
-void Nes_Dmc::recalc_irq()
-{
- nes_time_t irq = Nes_Apu::no_irq;
- if ( irq_enabled && length_counter )
- irq = apu->last_dmc_time + delay +
- ((length_counter - 1) * 8 + bits_remain - 1) * nes_time_t (period) + 1;
- if ( irq != next_irq ) {
- next_irq = irq;
- apu->irq_changed();
- }
-}
-
-int Nes_Dmc::count_reads( nes_time_t time, nes_time_t* last_read ) const
-{
- if ( last_read )
- *last_read = time;
-
- if ( length_counter == 0 )
- return 0; // not reading
-
- nes_time_t first_read = next_read_time();
- nes_time_t avail = time - first_read;
- if ( avail <= 0 )
- return 0;
-
- int count = (avail - 1) / (period * 8) + 1;
- if ( !(regs [0] & loop_flag) && count > length_counter )
- count = length_counter;
-
- if ( last_read )
- {
- *last_read = first_read + (count - 1) * (period * 8) + 1;
- check( *last_read <= time );
- check( count == count_reads( *last_read, NULL ) );
- check( count - 1 == count_reads( *last_read - 1, NULL ) );
- }
-
- return count;
-}
-
-static short const dmc_period_table [2] [16] = {
- {428, 380, 340, 320, 286, 254, 226, 214, // NTSC
- 190, 160, 142, 128, 106, 84, 72, 54},
-
- {398, 354, 316, 298, 276, 236, 210, 198, // PAL
- 176, 148, 132, 118, 98, 78, 66, 50}
-};
-
-inline void Nes_Dmc::reload_sample()
-{
- address = 0x4000 + regs [2] * 0x40;
- length_counter = regs [3] * 0x10 + 1;
-}
-
-static byte const dac_table [128] =
-{
- 0, 1, 2, 3, 4, 5, 6, 7, 7, 8, 9,10,11,12,13,14,
- 15,15,16,17,18,19,20,20,21,22,23,24,24,25,26,27,
- 27,28,29,30,31,31,32,33,33,34,35,36,36,37,38,38,
- 39,40,41,41,42,43,43,44,45,45,46,47,47,48,48,49,
- 50,50,51,52,52,53,53,54,55,55,56,56,57,58,58,59,
- 59,60,60,61,61,62,63,63,64,64,65,65,66,66,67,67,
- 68,68,69,70,70,71,71,72,72,73,73,74,74,75,75,75,
- 76,76,77,77,78,78,79,79,80,80,81,81,82,82,82,83,
-};
-
-void Nes_Dmc::write_register( int addr, int data )
-{
- if ( addr == 0 )
- {
- period = dmc_period_table [pal_mode] [data & 15];
- irq_enabled = (data & 0xC0) == 0x80; // enabled only if loop disabled
- irq_flag &= irq_enabled;
- recalc_irq();
- }
- else if ( addr == 1 )
- {
- int old_dac = dac;
- dac = data & 0x7F;
-
- // adjust last_amp so that "pop" amplitude will be properly non-linear
- // with respect to change in dac
- int faked_nonlinear = dac - (dac_table [dac] - dac_table [old_dac]);
- if ( !nonlinear )
- last_amp = faked_nonlinear;
- }
-}
-
-void Nes_Dmc::start()
-{
- reload_sample();
- fill_buffer();
- recalc_irq();
-}
-
-void Nes_Dmc::fill_buffer()
-{
- if ( !buf_full && length_counter )
- {
- require( prg_reader ); // prg_reader must be set
- buf = prg_reader( prg_reader_data, 0x8000u + address );
- address = (address + 1) & 0x7FFF;
- buf_full = true;
- if ( --length_counter == 0 )
- {
- if ( regs [0] & loop_flag ) {
- reload_sample();
- }
- else {
- apu->osc_enables &= ~0x10;
- irq_flag = irq_enabled;
- next_irq = Nes_Apu::no_irq;
- apu->irq_changed();
- }
- }
- }
-}
-
-void Nes_Dmc::run( nes_time_t time, nes_time_t end_time )
-{
- int delta = update_amp( dac );
- if ( !output )
- {
- silence = true;
- }
- else
- {
- output->set_modified();
- if ( delta )
- synth.offset( time, delta, output );
- }
-
- time += delay;
- if ( time < end_time )
- {
- int bits_remain = this->bits_remain;
- if ( silence && !buf_full )
- {
- int count = (end_time - time + period - 1) / period;
- bits_remain = (bits_remain - 1 + 8 - (count % 8)) % 8 + 1;
- time += count * period;
- }
- else
- {
- Blip_Buffer* const output = this->output;
- const int period = this->period;
- int bits = this->bits;
- int dac = this->dac;
-
- do
- {
- if ( !silence )
- {
- int step = (bits & 1) * 4 - 2;
- bits >>= 1;
- if ( unsigned (dac + step) <= 0x7F ) {
- dac += step;
- synth.offset_inline( time, step, output );
- }
- }
-
- time += period;
-
- if ( --bits_remain == 0 )
- {
- bits_remain = 8;
- if ( !buf_full ) {
- silence = true;
- }
- else {
- silence = false;
- bits = buf;
- buf_full = false;
- if ( !output )
- silence = true;
- fill_buffer();
- }
- }
- }
- while ( time < end_time );
-
- this->dac = dac;
- this->last_amp = dac;
- this->bits = bits;
- }
- this->bits_remain = bits_remain;
- }
- delay = time - end_time;
-}
-
-// Nes_Noise
-
-static short const noise_period_table [16] = {
- 0x004, 0x008, 0x010, 0x020, 0x040, 0x060, 0x080, 0x0A0,
- 0x0CA, 0x0FE, 0x17C, 0x1FC, 0x2FA, 0x3F8, 0x7F2, 0xFE4
-};
-
-void Nes_Noise::run( nes_time_t time, nes_time_t end_time )
-{
- int period = noise_period_table [regs [2] & 15];
-
- if ( !output )
- {
- // TODO: clean up
- time += delay;
- delay = time + (end_time - time + period - 1) / period * period - end_time;
- return;
- }
-
- output->set_modified();
-
- const int volume = this->volume();
- int amp = (noise & 1) ? volume : 0;
- {
- int delta = update_amp( amp );
- if ( delta )
- synth.offset( time, delta, output );
- }
-
- time += delay;
- if ( time < end_time )
- {
- const int mode_flag = 0x80;
-
- if ( !volume )
- {
- // round to next multiple of period
- time += (end_time - time + period - 1) / period * period;
-
- // approximate noise cycling while muted, by shuffling up noise register
- // to do: precise muted noise cycling?
- if ( !(regs [2] & mode_flag) ) {
- int feedback = (noise << 13) ^ (noise << 14);
- noise = (feedback & 0x4000) | (noise >> 1);
- }
- }
- else
- {
- Blip_Buffer* const output = this->output;
-
- // using resampled time avoids conversion in synth.offset()
- blip_resampled_time_t rperiod = output->resampled_duration( period );
- blip_resampled_time_t rtime = output->resampled_time( time );
-
- int noise = this->noise;
- int delta = amp * 2 - volume;
- const int tap = (regs [2] & mode_flag ? 8 : 13);
-
- do {
- int feedback = (noise << tap) ^ (noise << 14);
- time += period;
-
- if ( (noise + 1) & 2 ) {
- // bits 0 and 1 of noise differ
- delta = -delta;
- synth.offset_resampled( rtime, delta, output );
- }
-
- rtime += rperiod;
- noise = (feedback & 0x4000) | (noise >> 1);
- }
- while ( time < end_time );
-
- last_amp = (delta + volume) >> 1;
- this->noise = noise;
- }
- }
-
- delay = time - end_time;
-}
-
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