libretro/scummvm
1
0
Fork 0
mirror of https://github.com/libretro/scummvm.git synced 2024-12-14 13:50:13 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

cleanup (code easier to read; slightly less rounding errors for the volume; and on BE systems, READ_BE_UINT16 is actually faster ;-)

Browse Source 
svn-id: r8706
This commit is contained in:
Max Horn 2003-07-02 10:50:04 +00:00
parent cd269445f5
commit 01f992db9b
1 changed files with 12 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
sound/mixer.cpp
View File

@ -539,7 +539,7 @@ static int16 *mix_unsigned_stereo_8(int16 *data, uint *len_ptr, byte **s_ptr, ui
do {
do {
if (reverse_stereo == false) {
if (!reverse_stereo) {
*data = clamped_add_16(*data, left.interpolate(fp_pos));
data++;
*data = clamped_add_16(*data, right.interpolate(fp_pos));
@ -577,11 +577,11 @@ static int16 *mix_unsigned_stereo_8(int16 *data, uint *len_ptr, byte **s_ptr, ui
static int16 *mix_signed_mono_16(int16 *data, uint *len_ptr, byte **s_ptr, uint32 *fp_pos_ptr,
int fp_speed, const int16 *vol_tab, byte *s_end, bool reverse_stereo) {
uint32 fp_pos = *fp_pos_ptr;
unsigned char volume = ((int)vol_tab[1]) / 8;
unsigned char volume = ((int)vol_tab[1]);
byte *s = *s_ptr;
uint len = *len_ptr;
do {
int16 sample = (((int16)(*s << 8) | *(s + 1)) * volume) / 32;
int16 sample = ((int16)READ_BE_UINT16(s) * volume) / 256;
fp_pos += fp_speed;
*data = clamped_add_16(*data, sample);
@ -608,21 +608,24 @@ static int16 *mix_unsigned_mono_16(int16 *data, uint *len_ptr, byte **s_ptr, uin
static int16 *mix_signed_stereo_16(int16 *data, uint *len_ptr, byte **s_ptr, uint32 *fp_pos_ptr,
int fp_speed, const int16 *vol_tab, byte *s_end, bool reverse_stereo) {
uint32 fp_pos = *fp_pos_ptr;
unsigned char volume = ((int)vol_tab[1]) / 8;
unsigned char volume = (int)vol_tab[1];
byte *s = *s_ptr;
uint len = *len_ptr;
do {
int16 leftS = ((int16)READ_BE_UINT16(s) * volume) / 256;
int16 rightS = ((int16)READ_BE_UINT16(s+2) * volume) / 256;
fp_pos += fp_speed;
if (reverse_stereo == false) {
*data = clamped_add_16(*data, (((int16)(*(s) << 8) | *(s + 1)) * volume) / 32);
if (!reverse_stereo) {
*data = clamped_add_16(*data, leftS);
data++;
*data = clamped_add_16(*data, (((int16)(*(s + 2) << 8) | *(s + 3)) * volume) / 32);
*data = clamped_add_16(*data, rightS);
data++;
} else {
*data = clamped_add_16(*data, (((int16)(*(s + 2) << 8) | *(s + 3)) * volume) / 32);
*data = clamped_add_16(*data, rightS);
data++;
*data = clamped_add_16(*data, (((int16)(*(s) << 8) | *(s + 1)) * volume) / 32);
*data = clamped_add_16(*data, leftS);
data++;
}
s += (fp_pos >> 16) << 2;