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Removed doubles, reorganized code a bit

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This commit is contained in:
Lior Halphon 2016-09-13 16:55:56 +03:00
parent b95860c034
commit ff7b8a6854
3 changed files with 86 additions and 85 deletions
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53
Core/apu.c
View File

@ -18,10 +18,10 @@ _a < _b ? _a : _b; })
#define APU_FREQUENCY 0x80000
static int16_t generate_square(uint64_t phase, uint32_t wave_length, int16_t amplitude, double duty)
static int16_t generate_square(uint64_t phase, uint32_t wave_length, int16_t amplitude, uint8_t duty)
{
if (!wave_length) return 0;
if (phase % wave_length > wave_length * duty) {
if (phase % wave_length > wave_length * duty / 8) {
return amplitude;
}
return 0;
@ -58,16 +58,11 @@ static int16_t step_lfsr(uint16_t lfsr, bool uses_7_bit)
return lfsr;
}
/* General Todo: The APU emulation seems to fail many accuracy tests. It might require a rewrite with
these tests in mind. */
void GB_apu_run_internal(GB_gameboy_t *gb, unsigned int n_cycles, GB_sample_t *samples)
void GB_apu_get_samples_and_update_pcm_regs(GB_gameboy_t *gb, GB_sample_t *samples)
{
while (n_cycles--) {
if (n_cycles == 0) {
samples->left = samples->right = 0;
if (!gb->apu.global_enable) {
continue;
return;
}
gb->io_registers[GB_IO_PCM_12] = 0;
@ -117,6 +112,13 @@ void GB_apu_run_internal(GB_gameboy_t *gb, unsigned int n_cycles, GB_sample_t *s
samples->right *= gb->apu.right_volume;
}
/* General Todo: The APU emulation seems to fail many accuracy tests. It might require a rewrite with
these tests in mind. */
static void GB_apu_run_internal(GB_gameboy_t *gb)
{
for (;gb->apu.apu_cycles >= CPU_FREQUENCY/APU_FREQUENCY; gb->apu.apu_cycles -= CPU_FREQUENCY/APU_FREQUENCY) {
for (uint8_t i = 0; i < 4; i++) {
/* Phase */
gb->apu.wave_channels[i].phase++;
@ -130,19 +132,19 @@ void GB_apu_run_internal(GB_gameboy_t *gb, unsigned int n_cycles, GB_sample_t *s
/* Stop on Length */
if (gb->apu.wave_channels[i].stop_on_length) {
if (gb->apu.wave_channels[i].sound_length > 0) {
gb->apu.wave_channels[i].sound_length -= 1.0 / APU_FREQUENCY;
gb->apu.wave_channels[i].sound_length -= 1;
}
if (gb->apu.wave_channels[i].sound_length <= 0) {
gb->apu.wave_channels[i].amplitude = 0;
gb->apu.wave_channels[i].is_playing = false;
gb->apu.wave_channels[i].sound_length = i == 2? 1 : 0.25;
gb->apu.wave_channels[i].sound_length = i == 2? APU_FREQUENCY : APU_FREQUENCY / 4;
}
}
}
gb->apu.envelope_step_timer += 1.0 / APU_FREQUENCY;
if (gb->apu.envelope_step_timer >= 1.0 / 64) {
gb->apu.envelope_step_timer -= 1.0 / 64;
gb->apu.envelope_step_timer += 1;
if (gb->apu.envelope_step_timer >= APU_FREQUENCY / 64) {
gb->apu.envelope_step_timer -= APU_FREQUENCY / 64;
for (uint8_t i = 0; i < 4; i++) {
if (gb->apu.wave_channels[i].envelope_steps && !--gb->apu.wave_channels[i].cur_envelope_steps) {
gb->apu.wave_channels[i].amplitude = min(max(gb->apu.wave_channels[i].amplitude + gb->apu.wave_channels[i].envelope_direction * CH_STEP, 0), MAX_CH_AMP);
@ -151,9 +153,9 @@ void GB_apu_run_internal(GB_gameboy_t *gb, unsigned int n_cycles, GB_sample_t *s
}
}
gb->apu.sweep_step_timer += 1.0 / APU_FREQUENCY;
if (gb->apu.sweep_step_timer >= 1.0 / 128) {
gb->apu.sweep_step_timer -= 1.0 / 128;
gb->apu.sweep_step_timer += 1;
if (gb->apu.sweep_step_timer >= APU_FREQUENCY / 128) {
gb->apu.sweep_step_timer -= APU_FREQUENCY / 128;
if (gb->apu.wave_channels[0].sweep_steps && !--gb->apu.wave_channels[0].cur_sweep_steps) {
// Convert back to GB format
@ -181,13 +183,8 @@ void GB_apu_run(GB_gameboy_t *gb)
static bool should_log_overflow = true;
while (gb->audio_copy_in_progress);
double ticks_per_sample = (double) CPU_FREQUENCY / gb->sample_rate;
GB_sample_t sample = {0, };
if (gb->apu.apu_cycles >= CPU_FREQUENCY / APU_FREQUENCY) {
GB_apu_run_internal(gb, gb->apu.apu_cycles / (CPU_FREQUENCY / APU_FREQUENCY), &sample);
gb->apu.apu_cycles %= (CPU_FREQUENCY / APU_FREQUENCY);
gb->audio_buffer[gb->audio_position] = sample;
}
GB_apu_run_internal(gb);
if (gb->apu_sample_cycles > ticks_per_sample) {
gb->apu_sample_cycles -= ticks_per_sample;
@ -200,7 +197,7 @@ void GB_apu_run(GB_gameboy_t *gb)
*/
}
else {
gb->audio_position++;
GB_apu_get_samples_and_update_pcm_regs(gb, &gb->audio_buffer[gb->audio_position++]);
should_log_overflow = true;
}
}
@ -231,7 +228,7 @@ void GB_apu_copy_buffer(GB_gameboy_t *gb, GB_sample_t *dest, unsigned int count)
void GB_apu_init(GB_gameboy_t *gb)
{
memset(&gb->apu, 0, sizeof(gb->apu));
gb->apu.wave_channels[0].duty = gb->apu.wave_channels[1].duty = 0.5;
gb->apu.wave_channels[0].duty = gb->apu.wave_channels[1].duty = 4;
gb->apu.lfsr = 0x7FFF;
gb->apu.left_volume = 1.0;
gb->apu.right_volume = 1.0;
@ -281,7 +278,7 @@ uint8_t GB_apu_read(GB_gameboy_t *gb, uint8_t reg)
void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value)
{
static const double duties[] = {0.125, 0.25, 0.5, 0.75};
static const uint8_t duties[] = {1, 2, 4, 6}; /* Values are in 1/8 */
uint8_t channel = 0;
if (!gb->apu.global_enable && reg != GB_IO_NR52) {
@ -326,7 +323,7 @@ void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value)
case GB_IO_NR21:
case GB_IO_NR41:
gb->apu.wave_channels[channel].duty = duties[value >> 6];
gb->apu.wave_channels[channel].sound_length = (64 - (value & 0x3F)) / 256.0;
gb->apu.wave_channels[channel].sound_length = (64 - (value & 0x3F)) * (APU_FREQUENCY / 256);
if (gb->apu.wave_channels[channel].sound_length == 0) {
gb->apu.wave_channels[channel].is_playing = false;
}
@ -374,7 +371,7 @@ void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value)
gb->apu.wave_channels[2].is_playing &= gb->apu.wave_enable;
break;
case GB_IO_NR31:
gb->apu.wave_channels[2].sound_length = (256 - value) / 256.0;
gb->apu.wave_channels[2].sound_length = (256 - value) * (APU_FREQUENCY / 256);
if (gb->apu.wave_channels[2].sound_length == 0) {
gb->apu.wave_channels[2].is_playing = false;
}

18
Core/apu.h
View File

@ -19,21 +19,22 @@ typedef struct
} GB_sample_t;
/* Not all used on all channels */
/* All lengths are in APU ticks */
typedef struct
{
uint64_t phase;
uint32_t phase;
uint32_t wave_length;
GB_aligned_double duty;
GB_aligned_double sound_length; /* In seconds */
int32_t sound_length;
bool stop_on_length;
uint8_t duty;
int16_t amplitude;
int16_t start_amplitude;
bool stop_on_length;
uint8_t envelope_steps;
uint8_t cur_envelope_steps;
signed int envelope_direction;
int8_t envelope_direction;
uint8_t sweep_steps;
uint8_t cur_sweep_steps;
signed int sweep_direction;
int8_t sweep_direction;
uint8_t sweep_shift;
bool is_playing;
uint16_t NRX3_X4_temp;
@ -45,8 +46,8 @@ typedef struct
{
uint8_t apu_cycles;
bool global_enable;
GB_aligned_double envelope_step_timer; /* In seconds */
GB_aligned_double sweep_step_timer; /* In seconds */
uint32_t envelope_step_timer;
uint32_t sweep_step_timer;
int8_t wave_form[32];
uint8_t wave_shift;
bool wave_enable;
@ -60,6 +61,7 @@ typedef struct
void GB_apu_copy_buffer(GB_gameboy_t *gb, GB_sample_t *dest, unsigned int count);
void GB_apu_write(GB_gameboy_t *gb, uint8_t reg, uint8_t value);
uint8_t GB_apu_read(GB_gameboy_t *gb, uint8_t reg);
void GB_apu_get_samples_and_update_pcm_regs(GB_gameboy_t *gb, GB_sample_t *samples);
void GB_apu_init(GB_gameboy_t *gb);
void GB_apu_run(GB_gameboy_t *gb);

6
Core/memory.c
View File

@ -139,12 +139,14 @@ static uint8_t read_high_memory(GB_gameboy_t *gb, uint16_t addr)
}
return gb->io_registers[GB_IO_DMG_EMULATION_INDICATION] | 0xFE;
case GB_IO_PCM_12:
case GB_IO_PCM_34:
GB_apu_get_samples_and_update_pcm_regs(gb, &gb->audio_buffer[gb->audio_position]);
case GB_IO_HDMA1:
case GB_IO_HDMA2:
case GB_IO_HDMA3:
case GB_IO_HDMA4:
case GB_IO_PCM_12:
case GB_IO_PCM_34:
if (!gb->is_cgb) {
return 0xFF;
}