diff options
| -rw-r--r-- | sound/mixer.cpp | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/sound/mixer.cpp b/sound/mixer.cpp index cc24bf3a17..e5677bbde0 100644 --- a/sound/mixer.cpp +++ b/sound/mixer.cpp @@ -261,6 +261,7 @@ static int16 *mix_signed_mono_8(int16 *data, uint * len_ptr, byte **s_ptr, uint3 static int16 *mix_unsigned_mono_8(int16 *data, uint * len_ptr, byte **s_ptr, uint32 *fp_pos_ptr, int fp_speed, const int16 *vol_tab, byte *s_end) { +#if OLD uint32 fp_pos = *fp_pos_ptr; byte *s = *s_ptr; uint len = *len_ptr; @@ -277,6 +278,49 @@ static int16 *mix_unsigned_mono_8(int16 *data, uint * len_ptr, byte **s_ptr, uin *len_ptr = len; return data; +#else + uint32 fp_pos = *fp_pos_ptr; + byte *s = *s_ptr; + uint len = *len_ptr; + int x0, x1, x2, x3; + int a, b, c, d; + int inc = 1, result, t; + x0 = x1 = vol_tab[*s ^ 0x80]; + x2 = vol_tab[*(s+1) ^ 0x80]; + x3 = vol_tab[*(s+2) ^ 0x80]; + do { + a = ((-x0*2)+(x1*5)-(x2*4)+x3); + b = ((x0+x2-(2*x1))*6) << 8; + c = ((-4*x0)+x1+(x2*4)-x3) << 8; + d = (x1*6) << 8; + do { + t = fp_pos >> 8; + result = (a*t + b) >> 8; + result = (result * t + c) >> 8; + result = (result * t + d) >> 8; + result = (result/3 + 1) >> 1; + + *data++ += result; + *data++ += result; + + fp_pos += fp_speed; + inc = fp_pos >> 16; + s += inc; + fp_pos &= 0x0000FFFF; + } while ((--len) && !inc && (s < s_end)); + x0 = x1; + x1 = x2; + x2 = x3; + if (s+2 < s_end) + x3 = vol_tab[*(s+2) ^ 0x80]; + } while (len && (s < s_end)); + + *fp_pos_ptr = fp_pos; + *s_ptr = s; + *len_ptr = len; + + return data; +#endif } static int16 *mix_signed_stereo_8(int16 *data, uint * len_ptr, byte **s_ptr, uint32 *fp_pos_ptr, int fp_speed, const int16 *vol_tab, byte *s_end) |