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diff --git a/sid/sidplay-libs-2.1.0/resid/sid.cc b/sid/sidplay-libs-2.1.0/resid/sid.cc
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--- a/sid/sidplay-libs-2.1.0/resid/sid.cc
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@@ -1,856 +0,0 @@
-// ---------------------------------------------------------------------------
-// This file is part of reSID, a MOS6581 SID emulator engine.
-// Copyright (C) 2002 Dag Lem <resid@nimrod.no>
-//
-// This program is free software; you can redistribute it and/or modify
-// it under the terms of the GNU General Public License as published by
-// the Free Software Foundation; either version 2 of the License, or
-// (at your option) any later version.
-//
-// This program 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 General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program; if not, write to the Free Software
-// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-// ---------------------------------------------------------------------------
-
-#include "sid.h"
-#include <math.h>
-
-RESID_NAMESPACE_START
-
-const int SID::FIR_ORDER = RESID_FIR_ORDER;
-const int SID::FIR_N = RESID_FIR_N;
-const int SID::FIR_RES = RESID_FIR_RES;
-const int SID::FIR_SHIFT = RESID_FIR_SHIFT;
-
-// ----------------------------------------------------------------------------
-// Constructor.
-// ----------------------------------------------------------------------------
-SID::SID()
-{
- voice[0].set_sync_source(&voice[2]);
- voice[1].set_sync_source(&voice[0]);
- voice[2].set_sync_source(&voice[1]);
-
- set_sampling_parameters(985248, SAMPLE_FAST, 44100);
-}
-
-
-// ----------------------------------------------------------------------------
-// Set chip model.
-// ----------------------------------------------------------------------------
-void SID::set_chip_model(chip_model model)
-{
- for (int i = 0; i < 3; i++) {
- voice[i].set_chip_model(model);
- }
-
- filter.set_chip_model(model);
- extfilt.set_chip_model(model);
-}
-
-
-// ----------------------------------------------------------------------------
-// SID reset.
-// ----------------------------------------------------------------------------
-void SID::reset()
-{
- for (int i = 0; i < 3; i++) {
- voice[i].reset();
- }
- filter.reset();
- extfilt.reset();
-
- bus_value = 0;
- bus_value_ttl = 0;
-}
-
-
-// ----------------------------------------------------------------------------
-// Read sample of audio output.
-// Both 16-bit and n-bit output is provided.
-// ----------------------------------------------------------------------------
-int SID::output()
-{
- const int range = 1 << 16;
- const int half = range >> 1;
- int sample = extfilt.output()/((4095*255 >> 7)*3*15*2/range);
- if (sample >= half) {
- return half - 1;
- }
- if (sample < -half) {
- return -half;
- }
- return sample;
-}
-
-int SID::output(int bits)
-{
- const int range = 1 << bits;
- const int half = range >> 1;
- int sample = extfilt.output()/((4095*255 >> 7)*3*15*2/range);
- if (sample >= half) {
- return half - 1;
- }
- if (sample < -half) {
- return -half;
- }
- return sample;
-}
-
-
-// ----------------------------------------------------------------------------
-// Read registers.
-//
-// Reading a write only register returns the last byte written to any SID
-// register. The individual bits in this value start to fade down towards
-// zero after a few cycles. All bits reach zero within approximately
-// $2000 - $4000 cycles.
-// It has been claimed that this fading happens in an orderly fashion, however
-// sampling of write only registers reveals that this is not the case.
-// NB! This is not correctly modeled.
-// The actual use of write only registers has largely been made in the belief
-// that all SID registers are readable. To support this belief the read
-// would have to be done immediately after a write to the same register
-// (remember that an intermediate write to another register would yield that
-// value instead). With this in mind we return the last value written to
-// any SID register for $2000 cycles without modeling the bit fading.
-// ----------------------------------------------------------------------------
-reg8 SID::read(reg8 offset)
-{
- switch (offset) {
- case 0x19:
- return potx.readPOT();
- case 0x1a:
- return poty.readPOT();
- case 0x1b:
- return voice[2].wave.readOSC();
- case 0x1c:
- return voice[2].envelope.readENV();
- default:
- return bus_value;
- }
-}
-
-
-// ----------------------------------------------------------------------------
-// Write registers.
-// ----------------------------------------------------------------------------
-void SID::write(reg8 offset, reg8 value)
-{
- bus_value = value;
- bus_value_ttl = 0x2000;
-
- switch (offset) {
- case 0x00:
- voice[0].wave.writeFREQ_LO(value);
- break;
- case 0x01:
- voice[0].wave.writeFREQ_HI(value);
- break;
- case 0x02:
- voice[0].wave.writePW_LO(value);
- break;
- case 0x03:
- voice[0].wave.writePW_HI(value);
- break;
- case 0x04:
- voice[0].writeCONTROL_REG(value);
- break;
- case 0x05:
- voice[0].envelope.writeATTACK_DECAY(value);
- break;
- case 0x06:
- voice[0].envelope.writeSUSTAIN_RELEASE(value);
- break;
- case 0x07:
- voice[1].wave.writeFREQ_LO(value);
- break;
- case 0x08:
- voice[1].wave.writeFREQ_HI(value);
- break;
- case 0x09:
- voice[1].wave.writePW_LO(value);
- break;
- case 0x0a:
- voice[1].wave.writePW_HI(value);
- break;
- case 0x0b:
- voice[1].writeCONTROL_REG(value);
- break;
- case 0x0c:
- voice[1].envelope.writeATTACK_DECAY(value);
- break;
- case 0x0d:
- voice[1].envelope.writeSUSTAIN_RELEASE(value);
- break;
- case 0x0e:
- voice[2].wave.writeFREQ_LO(value);
- break;
- case 0x0f:
- voice[2].wave.writeFREQ_HI(value);
- break;
- case 0x10:
- voice[2].wave.writePW_LO(value);
- break;
- case 0x11:
- voice[2].wave.writePW_HI(value);
- break;
- case 0x12:
- voice[2].writeCONTROL_REG(value);
- break;
- case 0x13:
- voice[2].envelope.writeATTACK_DECAY(value);
- break;
- case 0x14:
- voice[2].envelope.writeSUSTAIN_RELEASE(value);
- break;
- case 0x15:
- filter.writeFC_LO(value);
- break;
- case 0x16:
- filter.writeFC_HI(value);
- break;
- case 0x17:
- filter.writeRES_FILT(value);
- break;
- case 0x18:
- filter.writeMODE_VOL(value);
- break;
- default:
- break;
- }
-}
-
-
-// ----------------------------------------------------------------------------
-// SID voice muting.
-// ----------------------------------------------------------------------------
-void SID::mute(reg8 channel, bool enable)
-{
- // Only have 3 voices!
- if (channel >= 3)
- return;
-
- voice[channel].mute (enable);
-}
-
-
-// ----------------------------------------------------------------------------
-// Constructor.
-// ----------------------------------------------------------------------------
-SID::State::State()
-{
- int i;
-
- for (i = 0; i < 0x20; i++) {
- sid_register[i] = 0;
- }
-
- bus_value = 0;
- bus_value_ttl = 0;
-
- for (i = 0; i < 3; i++) {
- accumulator[i] = 0;
- shift_register[i] = 0;
- rate_counter[i] = 0;
- exponential_counter[i] = 0;
- envelope_counter[i] = 0;
- hold_zero[i] = 0;
- }
-}
-
-
-// ----------------------------------------------------------------------------
-// Read state.
-// ----------------------------------------------------------------------------
-SID::State SID::read_state()
-{
- State state;
- int i, j;
-
- for (i = 0, j = 0; i < 3; i++, j += 7) {
- WaveformGenerator& wave = voice[i].wave;
- EnvelopeGenerator& envelope = voice[i].envelope;
- state.sid_register[j + 0] = wave.freq & 0xff;
- state.sid_register[j + 1] = wave.freq >> 8;
- state.sid_register[j + 2] = wave.pw & 0xff;
- state.sid_register[j + 3] = wave.pw >> 8;
- state.sid_register[j + 4] =
- (wave.waveform << 4)
- | (wave.test ? 0x08 : 0)
- | (wave.ring_mod ? 0x04 : 0)
- | (wave.sync ? 0x02 : 0)
- | (envelope.gate ? 0x01 : 0);
- state.sid_register[j + 5] = (envelope.attack << 4) | envelope.decay;
- state.sid_register[j + 6] = (envelope.decay << 4) | envelope.release;
- }
-
- state.sid_register[j++] = filter.fc & 0x007;
- state.sid_register[j++] = filter.fc >> 3;
- state.sid_register[j++] =
- (filter.res << 4)
- | (filter.filtex ? 0x08 : 0)
- | filter.filt3_filt2_filt1;
- state.sid_register[j++] =
- (filter.voice3off ? 0x80 : 0)
- | (filter.hp_bp_lp << 4)
- | filter.vol;
-
- // These registers are superfluous, but included for completeness.
- for (; j < 0x1d; j++) {
- state.sid_register[j] = read(j);
- }
- for (; j < 0x20; j++) {
- state.sid_register[j] = 0;
- }
-
- state.bus_value = bus_value;
- state.bus_value_ttl = bus_value_ttl;
-
- for (i = 0; i < 3; i++) {
- state.accumulator[i] = voice[i].wave.accumulator;
- state.shift_register[i] = voice[i].wave.shift_register;
- state.rate_counter[i] = voice[i].envelope.rate_counter;
- state.exponential_counter[i] = voice[i].envelope.exponential_counter;
- state.envelope_counter[i] = voice[i].envelope.envelope_counter;
- state.hold_zero[i] = voice[i].envelope.hold_zero;
- }
-
- return state;
-}
-
-
-// ----------------------------------------------------------------------------
-// Write state.
-// ----------------------------------------------------------------------------
-void SID::write_state(const State& state)
-{
- int i;
-
- for (i = 0; i < 0x18; i++) {
- write(i, state.sid_register[i]);
- }
-
- bus_value = state.bus_value;
- bus_value_ttl = state.bus_value_ttl;
-
- for (i = 0; i < 3; i++) {
- voice[i].wave.accumulator = state.accumulator[i];
- voice[i].wave.shift_register = state.shift_register[i];
- voice[i].envelope.rate_counter = state.rate_counter[i];
- voice[i].envelope.exponential_counter = state.exponential_counter[i];
- voice[i].envelope.envelope_counter = state.envelope_counter[i];
- voice[i].envelope.hold_zero = state.hold_zero[i];
- }
-}
-
-
-// ----------------------------------------------------------------------------
-// Enable filter.
-// ----------------------------------------------------------------------------
-void SID::enable_filter(bool enable)
-{
- filter.enable_filter(enable);
-}
-
-
-// ----------------------------------------------------------------------------
-// Enable external filter.
-// ----------------------------------------------------------------------------
-void SID::enable_external_filter(bool enable)
-{
- extfilt.enable_filter(enable);
-}
-
-
-// ----------------------------------------------------------------------------
-// I0() computes the 0th order modified Bessel function of the first kind.
-// This function is originally from resample-1.5/filterkit.c by J. O. Smith.
-// ----------------------------------------------------------------------------
-double SID::I0(double x)
-{
- // Max error acceptable in I0.
- const double I0e = 1E-21;
-
- double sum, u, halfx, temp;
- int n;
-
- sum = u = n = 1;
- halfx = x/2.0;
-
- do {
- temp = halfx/n++;
- u *= temp*temp;
- sum += u;
- } while (u >= I0e*sum);
-
- return sum;
-}
-
-
-// ----------------------------------------------------------------------------
-// Setting of SID sampling parameters.
-//
-// Use a clock freqency of 985248Hz for PAL C64, 1022730Hz for NTSC C64.
-// The default end of passband frequency is pass_freq = 0.9*sample_freq/2
-// for sample frequencies up to ~ 44.1kHz, and 20kHz for higher sample
-// frequencies.
-//
-// For resampling, the ratio between the clock frequency and the sample
-// frequency is limited as follows:
-// 123*clock_freq/sample_freq < 16384
-// E.g. provided a clock frequency of ~ 1MHz, the sample frequency can not
-// be set lower than ~ 8kHz. A lower sample frequency would make the
-// resampling code overfill its 16k sample ring buffer.
-//
-// The end of passband frequency is also limited:
-// pass_freq <= 0.9*sample_freq/2
-
-// E.g. for a 44.1kHz sampling rate the end of passband frequency is limited
-// to slightly below 20kHz. This constraint ensures that the FIR table is
-// not overfilled.
-// ----------------------------------------------------------------------------
-bool SID::set_sampling_parameters(double clock_freq, sampling_method method,
- double sample_freq, double pass_freq)
-{
- // Check resampling constraints.
- if (method == SAMPLE_RESAMPLE) {
- // Check whether the sample ring buffer would overfill.
- if (FIR_ORDER*clock_freq/sample_freq >= 16384) {
- return false;
- }
- }
-
- // The default passband limit is 0.9*sample_freq/2 for sample
- // frequencies below ~ 44.1kHz, and 20kHz for higher sample frequencies.
- if (pass_freq < 0) {
- pass_freq = 20000;
- if (2*pass_freq/sample_freq >= 0.9) {
- pass_freq = 0.9*sample_freq/2;
- }
- }
- // Check whether the FIR table would overfill.
- else if (pass_freq > 0.9*sample_freq/2) {
- return false;
- }
-
- // Set the external filter to the pass freq
- extfilt.set_sampling_parameter (pass_freq);
- clock_frequency = clock_freq;
- sampling = method;
-
- cycles_per_sample =
- cycle_count(clock_freq/sample_freq*(1 << 10) + 0.5);
-
- sample_offset = 0;
- sample_prev = 0;
-
- // FIR initialization is only necessary for resampling.
- if (sampling != SAMPLE_RESAMPLE) {
- return true;
- }
-
- const double pi = 3.1415926535897932385;
-
- // 16 bits -> -96dB stopband attenuation.
- const double A = -20*log10(1.0/(1 << 16));
- const double beta = 0.1102*(A - 8.7);
- const double I0beta = I0(beta);
-
- // A fraction of the bandwidth is allocated to the transition band,
- double dw = (1 - 2*pass_freq/sample_freq)*pi;
-
- // The filter order will maximally be 123 with the current constraints.
- // N >= (A - 8)/(2.285*0.1*pi) -> N >= 123
- int N = int((A - 8)/(2.285*dw) + 0.5);
- fir_N = 1 + N/2;
- foffset_max = fir_N*FIR_RES << 10;
-
- // The cutoff frequency is midway through the transition band.
- double wc = (2*pass_freq/sample_freq + 1)*pi/2;
-
- // Calculate FIR table. This is the right wing of the sinc function,
- // weighted by the Kaiser window.
- double samples_per_cycle = sample_freq/clock_freq;
- double val1, val2 = 0;
- for (int i = fir_N*FIR_RES; i > 0; i--) {
- double wt = wc*i/FIR_RES;
- double temp = double(i)/(fir_N*FIR_RES);
- val1 = (1 << FIR_SHIFT)*samples_per_cycle*wc/pi*sin(wt)/wt*I0(beta*sqrt(1.0 - temp*temp))/I0beta;
- fir[i] = short(val1 + 0.5);
- fir_diff[i] = short(val2 - val1 + 0.5);
- val2 = val1;
- }
- val1 = (1 << FIR_SHIFT)*samples_per_cycle*wc/pi;
- fir[0] = short(val1 + 0.5);
- fir_diff[0] = short(val2 - val1 + 0.5);
-
- // Calculate FIR constants.
- fstep_per_cycle =
- cycle_count(FIR_RES*sample_freq/clock_freq*(1 << 10) + 0.5);
- sample_delay = cycle_count(fir_N*clock_freq/sample_freq + 0.5);
-
- // Clear sample buffer.
- for (int j = 0; j < 4096; j++) {
- sample[j] = 0;
- }
- sample_index = 0;
-
- return true;
-}
-
-
-// ----------------------------------------------------------------------------
-// Adjustment of SID sampling frequency.
-//
-// In some applications, e.g. a C64 emulator, it can be desirable to
-// synchronize sound with a timer source. This is supported by adjustment of
-// the SID sampling frequency.
-//
-// NB! Adjustment of the sampling frequency may lead to noticeable shifts in
-// frequency, and should only be used for interactive applications. Note also
-// that any adjustment of the sampling frequency will change the
-// characteristics of the resampling filter, since the filter is not rebuilt.
-// ----------------------------------------------------------------------------
-void SID::adjust_sampling_frequency(double sample_freq)
-{
- cycles_per_sample =
- cycle_count(clock_frequency/sample_freq*(1 << 10) + 0.5);
-}
-
-
-// ----------------------------------------------------------------------------
-// Return array of default spline interpolation points to map FC to
-// filter cutoff frequency.
-// ----------------------------------------------------------------------------
-void SID::fc_default(const fc_point*& points, int& count)
-{
- filter.fc_default(points, count);
-}
-
-
-// ----------------------------------------------------------------------------
-// Return FC spline plotter object.
-// ----------------------------------------------------------------------------
-PointPlotter<sound_sample> SID::fc_plotter()
-{
- return filter.fc_plotter();
-}
-
-
-// ----------------------------------------------------------------------------
-// SID clocking - 1 cycle.
-// ----------------------------------------------------------------------------
-void SID::clock()
-{
- int i;
-
- // Age bus value.
- if (--bus_value_ttl <= 0) {
- bus_value = 0;
- bus_value_ttl = 0;
- }
-
- // Clock amplitude modulators.
- for (i = 0; i < 3; i++) {
- voice[i].envelope.clock();
- }
-
- // Clock oscillators.
- for (i = 0; i < 3; i++) {
- voice[i].wave.clock();
- }
-
- // Synchronize oscillators.
- for (i = 0; i < 3; i++) {
- voice[i].wave.synchronize();
- }
-
- // Clock filter.
- filter.clock(voice[0].output(), voice[1].output(), voice[2].output());
-
- // Clock external filter.
- extfilt.clock(filter.output());
-}
-
-
-// ----------------------------------------------------------------------------
-// SID clocking - delta_t cycles.
-// ----------------------------------------------------------------------------
-void SID::clock(cycle_count delta_t)
-{
- int i;
-
- if (delta_t <= 0) {
- return;
- }
-
- // Age bus value.
- bus_value_ttl -= delta_t;
- if (bus_value_ttl <= 0) {
- bus_value = 0;
- bus_value_ttl = 0;
- }
-
- // Clock amplitude modulators.
- for (i = 0; i < 3; i++) {
- voice[i].envelope.clock(delta_t);
- }
-
- // Clock and synchronize oscillators.
- // Loop until we reach the current cycle.
- cycle_count delta_t_osc = delta_t;
- while (delta_t_osc) {
- cycle_count delta_t_min = delta_t_osc;
-
- // Find minimum number of cycles to an oscillator accumulator MSB toggle.
- // We have to clock on each MSB on / MSB off for hard sync to operate
- // correctly.
- for (i = 0; i < 3; i++) {
- WaveformGenerator& wave = voice[i].wave;
-
- // It is only necessary to clock on the MSB of an oscillator that is
- // a sync source and has freq != 0.
- if (!(wave.sync_dest->sync && wave.freq)) {
- continue;
- }
-
- reg16 freq = wave.freq;
- reg24 accumulator = wave.accumulator;
-
- // Clock on MSB off if MSB is on, clock on MSB on if MSB is off.
- reg24 delta_accumulator =
- (accumulator & 0x800000 ? 0x1000000 : 0x800000) - accumulator;
-
- cycle_count delta_t_next = delta_accumulator/freq;
- if (delta_accumulator%freq) {
- ++delta_t_next;
- }
-
- if (delta_t_next < delta_t_min) {
- delta_t_min = delta_t_next;
- }
- }
-
- // Clock oscillators.
- for (i = 0; i < 3; i++) {
- voice[i].wave.clock(delta_t_min);
- }
-
- // Synchronize oscillators.
- for (i = 0; i < 3; i++) {
- voice[i].wave.synchronize();
- }
-
- delta_t_osc -= delta_t_min;
- }
-
- // Clock filter.
- filter.clock(delta_t,
- voice[0].output(), voice[1].output(), voice[2].output());
-
- // Clock external filter.
- extfilt.clock(delta_t, filter.output());
-}
-
-
-// ----------------------------------------------------------------------------
-// SID clocking with audio sampling.
-// Fixpoint arithmetic (22.10 bits) is used.
-//
-// The example below shows how to clock the SID a specified amount of cycles
-// while producing audio output:
-//
-// while (delta_t) {
-// bufindex += sid.clock(delta_t, buf + bufindex, buflength - bufindex);
-// write(dsp, buf, bufindex*2);
-// bufindex = 0;
-// }
-//
-// ----------------------------------------------------------------------------
-int SID::clock(cycle_count& delta_t, short* buf, int n, int interleave)
-{
- switch (sampling) {
- default:
- case SAMPLE_FAST:
- return clock_fast(delta_t, buf, n, interleave);
- case SAMPLE_INTERPOLATE:
- return clock_interpolate(delta_t, buf, n, interleave);
- case SAMPLE_RESAMPLE:
- return clock_resample(delta_t, buf, n, interleave);
- }
-}
-
-// ----------------------------------------------------------------------------
-// SID clocking with audio sampling - delta clocking picking nearest sample.
-// ----------------------------------------------------------------------------
-RESID_INLINE
-int SID::clock_fast(cycle_count& delta_t, short* buf, int n,
- int interleave)
-{
- int s = 0;
-
- for (;;) {
- cycle_count next_sample_offset = sample_offset + cycles_per_sample + (1 << 9);
- cycle_count delta_t_sample = next_sample_offset >> 10;
- if (delta_t_sample > delta_t) {
- break;
- }
- if (s >= n) {
- return s;
- }
- clock(delta_t_sample);
- delta_t -= delta_t_sample;
- sample_offset = (next_sample_offset & 0x3ff) - (1 << 9);
- buf[s++*interleave] = output();
- }
-
- clock(delta_t);
- sample_offset -= delta_t << 10;
- delta_t = 0;
- return s;
-}
-
-
-// ----------------------------------------------------------------------------
-// SID clocking with audio sampling - cycle based with linear sample
-// interpolation.
-//
-// Here the chip is clocked every cycle. This yields higher quality
-// sound since the samples are linearly interpolated, and since the
-// external filter attenuates frequencies above 16kHz, thus reducing
-// sampling noise.
-// ----------------------------------------------------------------------------
-RESID_INLINE
-int SID::clock_interpolate(cycle_count& delta_t, short* buf, int n,
- int interleave)
-{
- int s = 0;
- int i;
-
- for (;;) {
- cycle_count next_sample_offset = sample_offset + cycles_per_sample;
- cycle_count delta_t_sample = next_sample_offset >> 10;
- if (delta_t_sample > delta_t) {
- break;
- }
- if (s >= n) {
- return s;
- }
- for (i = 0; i < delta_t_sample - 1; i++) {
- clock();
- }
- if (i < delta_t_sample) {
- sample_prev = output();
- clock();
- }
-
- delta_t -= delta_t_sample;
- sample_offset = next_sample_offset & 0x3ff;
-
- short sample_now = output();
- buf[s++*interleave] =
- sample_prev + (sample_offset*(sample_now - sample_prev) >> 10);
- sample_prev = sample_now;
- }
-
- for (i = 0; i < delta_t - 1; i++) {
- clock();
- }
- if (i < delta_t) {
- sample_prev = output();
- clock();
- }
- sample_offset -= delta_t << 10;
- delta_t = 0;
- return s;
-}
-
-
-// ----------------------------------------------------------------------------
-// SID clocking with audio sampling - cycle based with audio resampling.
-//
-// This is the theoretically correct (and computationally intensive) audio
-// sample generation. The samples are generated by resampling to the specified
-// sampling frequency. The work rate is inversely proportional to the
-// percentage of the bandwidth allocated to the filter transition band.
-//
-// This implementation is based on the paper "A Flexible Sampling-Rate
-// Conversion Method", by J. O. Smith and P. Gosset, or rather on the
-// expanded tutorial on the "Digital Audio Resampling Home Page":
-// http://www-ccrma.stanford.edu/~jos/resample/
-//
-// NB! The sample ring buffer requires two's complement integer, and
-// the result of right shifting negative numbers is really implementation
-// dependent in the C++ standard. It is crucial for speed, however.
-// ----------------------------------------------------------------------------
-RESID_INLINE
-int SID::clock_resample(cycle_count& delta_t, short* buf, int n,
- int interleave)
-{
- int s = 0;
-
- for (;;) {
- cycle_count next_sample_offset = sample_offset + cycles_per_sample;
- cycle_count delta_t_sample = next_sample_offset >> 10;
- if (delta_t_sample > delta_t) {
- break;
- }
- if (s >= n) {
- return s;
- }
- for (int i = 0; i < delta_t_sample; i++) {
- clock();
- sample[sample_index++] = output();
- sample_index &= 0x3fff;
- }
- delta_t -= delta_t_sample;
- sample_offset = next_sample_offset & 0x3ff;
-
- int v = 0;
- int filter_offset = sample_offset*fstep_per_cycle >> 10;
- int foffset;
-
- // Convolution with right wing of filter impulse response.
- unsigned int j = (sample_index - sample_delay - 1) & 0x3fff;
- for (foffset = filter_offset;
- foffset <= foffset_max;
- foffset += fstep_per_cycle)
- {
- int findex = foffset >> 10;
- int frmd = foffset & 0x3ff;
- v += sample[j--]*(fir[findex] + (frmd*fir_diff[findex] >> 10));
- j &= 0x3fff;
- }
-
- // Convolution with left wing of filter impulse response.
- j = (sample_index - sample_delay) & 0x3fff;
- for (foffset = fstep_per_cycle - filter_offset;
- foffset <= foffset_max;
- foffset += fstep_per_cycle)
- {
- int findex = foffset >> 10;
- int frmd = foffset & 0x3ff;
- v += sample[j++]*(fir[findex] + (frmd*fir_diff[findex] >> 10));
- j &= 0x3fff;
- }
-
- buf[s++*interleave] = v >> FIR_SHIFT;
- }
-
- for (int i = 0; i < delta_t; i++) {
- clock();
- sample[sample_index++] = output();
- sample_index &= 0x3fff;
- }
- sample_offset -= delta_t << 10;
- delta_t = 0;
- return s;
-}
-
-RESID_NAMESPACE_STOP