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authorChris Robinson <[email protected]>2013-05-18 00:43:09 -0700
committerChris Robinson <[email protected]>2013-05-18 00:43:09 -0700
commita7ad6080f0d3fc783fd5e1811b961ab9efe79cde (patch)
treecf55c6a36fa94c1074dc2adbd664e08f86c0df34
parent563f16dc2a52de3217c90313ca6bddbbc20f20a0 (diff)
Modulator fixes
Modulator functions return 0..1 instead of -1..+1 Apply high-pass filter before modulation Increase fractional precision to 24 bits from 16 Thanks to Mike Gorchak
-rw-r--r--Alc/alcModulator.c11
1 files changed, 5 insertions, 6 deletions
diff --git a/Alc/alcModulator.c b/Alc/alcModulator.c
index 05b2fb00..f1f8dadd 100644
--- a/Alc/alcModulator.c
+++ b/Alc/alcModulator.c
@@ -49,23 +49,23 @@ typedef struct ALmodulatorState {
ALfloat history[1];
} ALmodulatorState;
-#define WAVEFORM_FRACBITS 16
+#define WAVEFORM_FRACBITS 24
#define WAVEFORM_FRACONE (1<<WAVEFORM_FRACBITS)
#define WAVEFORM_FRACMASK (WAVEFORM_FRACONE-1)
static __inline ALfloat Sin(ALuint index)
{
- return sinf(index * (F_PI*2.0f / WAVEFORM_FRACONE));
+ return sinf(index * (F_PI*2.0f / WAVEFORM_FRACONE) - F_PI)*0.5f + 0.5f;
}
static __inline ALfloat Saw(ALuint index)
{
- return index*(2.0f/WAVEFORM_FRACONE) - 1.0f;
+ return (ALfloat)index / WAVEFORM_FRACONE;
}
static __inline ALfloat Square(ALuint index)
{
- return ((index>>(WAVEFORM_FRACBITS-1))&1)*2.0f - 1.0f;
+ return (ALfloat)((index >> (WAVEFORM_FRACBITS - 1)) & 1);
}
@@ -95,13 +95,12 @@ static void Process##func(ALmodulatorState *state, ALuint SamplesToDo, \
for(i = 0;i < SamplesToDo;i++) \
{ \
samp = SamplesIn[i]; \
+ samp = hpFilter1P(&state->iirFilter, 0, samp); \
\
index += step; \
index &= WAVEFORM_FRACMASK; \
samp *= func(index); \
\
- samp = hpFilter1P(&state->iirFilter, 0, samp); \
- \
for(k = 0;k < MaxChannels;k++) \
SamplesOut[k][i] += state->Gain[k] * samp; \
} \