Minor free optimization

This commit is contained in:
Lior Halphon 2021-12-29 16:33:04 +02:00
parent b72c2ea225
commit 59c315a5dd
1 changed files with 7 additions and 5 deletions

View File

@ -64,6 +64,13 @@ static uint8_t agb_bias_for_channel(GB_gameboy_t *gb, unsigned index)
static void update_sample(GB_gameboy_t *gb, unsigned index, int8_t value, unsigned cycles_offset)
{
if (gb->model >= GB_MODEL_AGB && index == GB_WAVE) {
/* For some reason, channel 3 is inverted on the AGB */
value ^= 0xF;
}
if (value == 0 && gb->apu.samples[index] == 0) return;
if (gb->model >= GB_MODEL_AGB) {
/* On the AGB, because no analog mixing is done, the behavior of NR51 is a bit different.
A channel that is not connected to a terminal is idenitcal to a connected channel
@ -74,11 +81,6 @@ static void update_sample(GB_gameboy_t *gb, unsigned index, int8_t value, unsign
unsigned right_volume = (gb->io_registers[GB_IO_NR50] & 7) + 1;
unsigned left_volume = ((gb->io_registers[GB_IO_NR50] >> 4) & 7) + 1;
if (index == GB_WAVE) {
/* For some reason, channel 3 is inverted on the AGB */
value ^= 0xF;
}
GB_sample_t output;
uint8_t bias = agb_bias_for_channel(gb, index);