furnace/src/engine/platform/sound/supervision.c
2024-09-02 11:43:22 +03:00

283 lines
9.9 KiB
C

// THIS IS A MODIFIED VERSION OF POTATOR'S SOUND EMULATION CORE
// MODIFIED BY AART1256 IN 2024
#include "supervision.h"
#include <string.h>
#define SV_SAMPLE_RATE ((svision->UNSCALED_CLOCK)/64)
#define SV_DEC_TICK ((SV_SAMPLE_RATE)/60)
void supervision_sound_set_clock(struct svision_t *svision, uint32 clock) {
svision->UNSCALED_CLOCK = clock;
}
void supervision_memorymap_registers_write(struct svision_t *svision, uint32 Addr, uint8 Value)
{
switch (Addr & 0x1fff) {
case 0x10: case 0x11: case 0x12: case 0x13:
case 0x14: case 0x15: case 0x16: case 0x17:
supervision_sound_wave_write(svision, ((Addr & 0x4) >> 2), Addr & 3, Value);
break;
case 0x18:
case 0x19:
case 0x1a:
case 0x1b:
case 0x1c:
supervision_sound_dma_write(svision, Addr & 0x07, Value);
break;
case 0x28:
case 0x29:
case 0x2a:
supervision_sound_noise_write(svision, Addr & 0x07, Value);
break;
}
}
void supervision_set_mute_mask(struct svision_t *svision, uint8 mask) {
svision->ch_mask = mask;
}
void supervision_sound_set_flags(struct svision_t *svision, uint8 flags_set)
{
svision->flags = flags_set;
}
void supervision_sound_reset(struct svision_t *svision)
{
memset(svision->m_channel, 0, sizeof(svision->m_channel));
memset(&svision->m_noise, 0, sizeof(svision->m_noise) );
memset(&svision->m_dma, 0, sizeof(svision->m_dma) );
memset(svision->ch, 0, sizeof(svision->ch) );
svision->decrement_tick = 0;
svision->ch_mask = 15;
}
void supervision_sound_stream_update(struct svision_t *svision, uint8 *stream, uint32 len)
{
size_t i, j;
SVISION_CHANNEL *channel;
uint8 s = 0;
uint8 *left = stream + 0;
uint8 *right = stream + 1;
uint8 *chout = stream + 2;
for (i = 0; i < len >> 1; i++, left += 2, right += 2) {
*left = *right = 0;
for (channel = svision->m_channel, j = 0; j < 2; j++, channel++) {
chout[j] = 0;
if (svision->ch[j].size != 0) {
if (svision->ch[j].on || channel->count != 0) {
BOOL on = 0;
switch (svision->ch[j].waveform) {
case 0: // 12.5%
on = svision->ch[j].pos < (28 * svision->ch[j].size) >> 5;
break;
case 1: // 25%
on = svision->ch[j].pos < (24 * svision->ch[j].size) >> 5;
break;
case 2: // 50%
on = svision->ch[j].pos < svision->ch[j].size / 2;
break;
case 3: // 75%
on = svision->ch[j].pos < svision->ch[j].size / 4;
// MESS/MAME: <= (9 * svision->ch[j].size) >> 5;
break;
}
s = on ? (svision->ch[j].volume)<<2 : 0;
s = ((svision->ch_mask>>(3-j))&1)?s:0;
if (svision->flags&1) {
if (j == 0)
*right += s;
else
*left += s;
} else {
*left += s;
*right += s;
}
chout[j] = s;
}
svision->ch[j].pos++;
if (svision->ch[j].pos >= svision->ch[j].size) {
svision->ch[j].pos = 0;
// Transition from off to on
if (channel->on) {
memcpy(&svision->ch[j], channel, sizeof(svision->ch[j]));
channel->on = 0;
}
}
}
}
if (svision->m_noise.on && (svision->m_noise.play || svision->m_noise.count != 0)) {
s = (svision->m_noise.value * svision->m_noise.volume) << 2;
s = svision->ch_mask&1?s:0;
chout[3] = 0;
if (svision->m_noise.left) {
*left += s;
chout[3] = s;
}
if (svision->m_noise.right) {
*right += s;
chout[3] = s;
}
svision->m_noise.pos += svision->m_noise.step;
while (svision->m_noise.pos >= 1.0) { // if/while difference - Pacific Battle
// LFSR: x^2 + x + 1
uint16 feedback;
svision->m_noise.value = svision->m_noise.state & 1;
feedback = ((svision->m_noise.state >> 1) ^ svision->m_noise.state) & 0x0001;
feedback <<= svision->m_noise.type;
svision->m_noise.state = (svision->m_noise.state >> 1) | feedback;
svision->m_noise.pos -= 1.0;
}
}
chout[2] = 0;
if (svision->m_dma.on) {
uint8 sample;
uint16 addr = svision->m_dma.start + (uint16)svision->m_dma.pos / 2;
if (addr >= 0x8000 && addr < 0xc000) {
sample = svision->supervision_dma_mem[(addr & 0x3fff) | svision->m_dma.ca14to16];
}
if (((uint16)svision->m_dma.pos) & 1)
s = (sample & 0xf);
else
s = (sample & 0xf0) >> 4;
s <<= 2;
s = ((svision->ch_mask>>1)&1)?s:0;
chout[2] = 0;
if (svision->m_dma.left) {
*left += s;
chout[2] = s;
}
if (svision->m_dma.right) {
*right += s;
chout[2] = s;
}
svision->m_dma.pos += svision->m_dma.step;
if (svision->m_dma.pos >= svision->m_dma.size) {
svision->m_dma.on = 0;
}
}
if (svision->decrement_tick > SV_DEC_TICK) {
svision->decrement_tick = 0;
supervision_sound_decrement(svision);
}
svision->decrement_tick++;
}
}
void supervision_sound_decrement(struct svision_t *svision)
{
if (svision->m_channel[0].count > 0)
svision->m_channel[0].count--;
if (svision->m_channel[1].count > 0)
svision->m_channel[1].count--;
if (svision->m_noise.count > 0)
svision->m_noise.count--;
}
void supervision_sound_wave_write(struct svision_t *svision, int which, int offset, uint8 data)
{
SVISION_CHANNEL *channel = &svision->m_channel[which];
channel->reg[offset] = data;
switch (offset) {
case 0:
case 1: {
uint16 size;
size = channel->reg[0] | ((channel->reg[1] & 7) << 8);
// if size == 0 then channel->size == 0
if (size)
channel->size = (uint16)(((real)SV_SAMPLE_RATE) * ((real)((size + 1) << 5)) / ((real)svision->UNSCALED_CLOCK));
else
channel->size = 0;
channel->pos = 0;
// Popo Team
if (channel->count != 0 || svision->ch[which].size == 0 || channel->size == 0) {
svision->ch[which].size = channel->size;
if (channel->count == 0)
svision->ch[which].pos = 0;
}
}
break;
case 2:
channel->on = data & 0x40;
channel->waveform = (data & 0x30) >> 4;
channel->volume = data & 0x0f;
if (!channel->on || svision->ch[which].size == 0 || channel->size == 0) {
uint16 pos = svision->ch[which].pos;
memcpy(&svision->ch[which], channel, sizeof(svision->ch[which]));
if (channel->count != 0) // Journey to the West
svision->ch[which].pos = pos;
}
break;
case 3:
channel->count = data + 1;
svision->ch[which].size = channel->size; // Sonny Xpress!
break;
}
}
void supervision_sound_dma_write(struct svision_t *svision, int offset, uint8 data)
{
svision->m_dma.reg[offset] = data;
switch (offset) {
case 0:
case 1:
svision->m_dma.start = (svision->m_dma.reg[0] | (svision->m_dma.reg[1] << 8));
break;
case 2:
svision->m_dma.size = (data ? data : 0x100) * 32; // Number of 4-bit samples
break;
case 3:
// Test games: Classic Casino, SSSnake
svision->m_dma.step = ((real)svision->UNSCALED_CLOCK) / ((real)SV_SAMPLE_RATE * (256 << (data & 3)));
// MESS/MAME. Wrong
//svision->m_dma.step = svision->UNSCALED_CLOCK / (256.0 * SV_SAMPLE_RATE * (1 + (data & 3)));
svision->m_dma.right = data & 4;
svision->m_dma.left = data & 8;
svision->m_dma.ca14to16 = ((data & 0x70) >> 4) << 14;
break;
case 4:
svision->m_dma.on = data & 0x80;
if (svision->m_dma.on) {
svision->m_dma.pos = 0.0;
}
break;
}
}
void supervision_sound_noise_write(struct svision_t *svision, int offset, uint8 data)
{
svision->m_noise.reg[offset] = data;
switch (offset) {
case 0: {
uint32 divisor = 8 << (data >> 4);
if (divisor)
svision->m_noise.step = ((real)svision->UNSCALED_CLOCK) / ((real)SV_SAMPLE_RATE * divisor);
else
svision->m_noise.step = 0;
svision->m_noise.step = ((real)svision->UNSCALED_CLOCK) / ((real)SV_SAMPLE_RATE * divisor);
svision->m_noise.volume = data & 0xf;
}
break;
case 1:
svision->m_noise.count = data + 1;
break;
case 2:
svision->m_noise.type = (data & 1) ? 14 : 6;
svision->m_noise.play = data & 2;
svision->m_noise.right = data & 4;
svision->m_noise.left = data & 8;
svision->m_noise.on = data & 0x10; /* honey bee start */
svision->m_noise.state = 1;
break;
}
svision->m_noise.pos = 0.0;
}