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Mixer code cleanup: fixing ESS volume calculation

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This commit is contained in:
Kagamiin~
2024-03-22 01:31:13 -03:00
parent c835a4d156
commit 3e539c630b
1 changed files with 9 additions and 20 deletions
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29
src/sound/snd_ess.c
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@@ -50,7 +50,7 @@
#include <86box/plat_unused.h> #include <86box/plat_unused.h>
// clang-format off
static const double sb_att_4dbstep_3bits[] = { static const double sb_att_4dbstep_3bits[] = {
164.0, 2067.0, 3276.0, 5193.0, 8230.0, 13045.0, 20675.0, 32767.0 164.0, 2067.0, 3276.0, 5193.0, 8230.0, 13045.0, 20675.0, 32767.0
}; };
@@ -64,6 +64,13 @@ static const double sb_att_1p4dbstep_4bits[] = {
10603.0, 12458.0, 14637.0, 17196.0, 20204.0, 23738.0, 27889.0, 32767.0 10603.0, 12458.0, 14637.0, 17196.0, 20204.0, 23738.0, 27889.0, 32767.0
}; };
static const double sb_att_2dbstep_4bits[] = {
164.0, 1304.0, 1641.0, 2067.0, 2602.0, 3276.0, 4125.0, 5192.0,
6537.0, 8230.0, 10362.0, 13044.0, 16422.0, 20674.0, 26027.0, 32767.0
};
// clang-format on
/* SB PRO */ /* SB PRO */
typedef struct ess_mixer_t { typedef struct ess_mixer_t {
double master_l; double master_l;
@@ -118,27 +125,9 @@ typedef struct ess_t {
void (*opl_mix)(void*, double*, double*); void (*opl_mix)(void*, double*, double*);
} ess_t; } ess_t;
static inline uint8_t expand16to32(const uint8_t t) {
/* 4-bit -> 5-bit expansion.
*
* 0 -> 0
* 1 -> 2
* 2 -> 4
* 3 -> 6
* ....
* 7 -> 14
* 8 -> 17
* 9 -> 19
* 10 -> 21
* 11 -> 23
* ....
* 15 -> 31 */
return (t << 1) | (t >> 3);
}
static double ess_mixer_get_vol_4bit(uint8_t vol) static double ess_mixer_get_vol_4bit(uint8_t vol)
{ {
return (48.0 + (20.0 * log((vol & 0xF) / 15.0))) / 48.0; return sb_att_2dbstep_4bits[vol] / 32767.0;
} }
void void