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De-macroize render_sample macros

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twinaphex 2014-12-09 21:21:09 +01:00
parent 01ac6359fd
commit 99e6e574d3
1 changed files with 45 additions and 33 deletions
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78
sound.c
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@ -69,34 +69,6 @@ void sound_timer_queue32(u32 channel, u32 value)
sound_timer_queue(8, value >> 24); sound_timer_queue(8, value >> 24);
} }
// Unqueue 1 sample from the base of the DS FIFO and place it on the audio
// buffer for as many samples as necessary. If the DS FIFO is 16 bytes or
// smaller and if DMA is enabled for the sound channel initiate a DMA transfer
// to the DS FIFO.
#define render_sample_null() \
#define render_sample_left() \
sound_buffer[buffer_index] += current_sample + \
fp16_16_to_u32((next_sample - current_sample) * (fifo_fractional >> 8)) \
#define render_sample_right() \
sound_buffer[buffer_index + 1] += current_sample + \
fp16_16_to_u32((next_sample - current_sample) * (fifo_fractional >> 8)) \
#define render_sample_both() \
dest_sample = current_sample + \
fp16_16_to_u32((next_sample - current_sample) * (fifo_fractional >> 8)); \
sound_buffer[buffer_index] += dest_sample; \
sound_buffer[buffer_index + 1] += dest_sample \
#define render_samples(type) \
while(fifo_fractional <= 0xFFFFFF) \
{ \
render_sample_##type(); \
fifo_fractional += frequency_step; \
buffer_index = (buffer_index + 2) % BUFFER_SIZE; \
} \
void sound_timer(fixed8_24 frequency_step, u32 channel) void sound_timer(fixed8_24 frequency_step, u32 channel)
{ {
@ -105,7 +77,7 @@ void sound_timer(fixed8_24 frequency_step, u32 channel)
fixed8_24 fifo_fractional = ds->fifo_fractional; fixed8_24 fifo_fractional = ds->fifo_fractional;
u32 buffer_index = ds->buffer_index; u32 buffer_index = ds->buffer_index;
s16 current_sample, next_sample, dest_sample; s16 current_sample, next_sample;
current_sample = ds->fifo[ds->fifo_base] << 4; current_sample = ds->fifo[ds->fifo_base] << 4;
ds->fifo_base = (ds->fifo_base + 1) % 32; ds->fifo_base = (ds->fifo_base + 1) % 32;
@ -123,22 +95,62 @@ void sound_timer(fixed8_24 frequency_step, u32 channel)
} }
// Unqueue 1 sample from the base of the DS FIFO and place it on the audio
// buffer for as many samples as necessary. If the DS FIFO is 16 bytes or
// smaller and if DMA is enabled for the sound channel initiate a DMA transfer
// to the DS FIFO.
switch(sample_status) switch(sample_status)
{ {
case DIRECT_SOUND_INACTIVE: case DIRECT_SOUND_INACTIVE:
render_samples(null); /* render samples NULL */
while(fifo_fractional <= 0xFFFFFF)
{
fifo_fractional += frequency_step;
buffer_index = (buffer_index + 2) % BUFFER_SIZE;
}
break; break;
case DIRECT_SOUND_RIGHT: case DIRECT_SOUND_RIGHT:
render_samples(right); /* render samples RIGHT */
while(fifo_fractional <= 0xFFFFFF)
{
s16 dest_sample = current_sample +
fp16_16_to_u32((next_sample - current_sample) * (fifo_fractional >> 8));
sound_buffer[buffer_index + 1] += dest_sample;
fifo_fractional += frequency_step;
buffer_index = (buffer_index + 2) % BUFFER_SIZE;
}
break; break;
case DIRECT_SOUND_LEFT: case DIRECT_SOUND_LEFT:
render_samples(left); /* render samples LEFT */
while(fifo_fractional <= 0xFFFFFF)
{
s16 dest_sample = current_sample +
fp16_16_to_u32((next_sample - current_sample) * (fifo_fractional >> 8));
sound_buffer[buffer_index] += dest_sample;
fifo_fractional += frequency_step;
buffer_index = (buffer_index + 2) % BUFFER_SIZE;
}
break; break;
case DIRECT_SOUND_LEFTRIGHT: case DIRECT_SOUND_LEFTRIGHT:
render_samples(both); /* render samples LEFT and RIGHT. */
while(fifo_fractional <= 0xFFFFFF)
{
s16 dest_sample = current_sample +
fp16_16_to_u32((next_sample - current_sample) * (fifo_fractional >> 8));
sound_buffer[buffer_index] += dest_sample;
sound_buffer[buffer_index + 1] += dest_sample;
fifo_fractional += frequency_step;
buffer_index = (buffer_index + 2) % BUFFER_SIZE;
}
break; break;
} }