mirror of
https://github.com/ZDoom/gzdoom.git
synced 2024-12-11 05:00:58 +00:00
a8de4fc2da
everything that was new for XP. - Swapped snes_spc out for the full Game Music Emu library. SVN r1631 (trunk)
551 lines
12 KiB
C++
551 lines
12 KiB
C++
// 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;
|
|
}
|
|
|