diff options
| -rw-r--r-- | alc/effects/vmorpher.cpp | 37 |
1 files changed, 22 insertions, 15 deletions
diff --git a/alc/effects/vmorpher.cpp b/alc/effects/vmorpher.cpp index c451bedb..d24d41d6 100644 --- a/alc/effects/vmorpher.cpp +++ b/alc/effects/vmorpher.cpp @@ -78,40 +78,47 @@ void Oscillate(ALfloat *RESTRICT dst, ALuint index, const ALuint step, size_t to struct FormantFilter { - ALfloat f0norm{0.0f}; - ALfloat fGain{1.0f}; - ALfloat s1{0.0f}; - ALfloat s2{0.0f}; + ALfloat mCoeff{0.0f}; + ALfloat mGain{1.0f}; + ALfloat mS1{0.0f}; + ALfloat mS2{0.0f}; FormantFilter() = default; - FormantFilter(ALfloat f0norm_, ALfloat gain) : f0norm{f0norm_}, fGain{gain} { } + FormantFilter(ALfloat f0norm, ALfloat gain) + : mCoeff{std::tan(al::MathDefs<float>::Pi() * f0norm)}, mGain{gain} + { } inline void process(const ALfloat *samplesIn, ALfloat *samplesOut, const size_t numInput) { /* A state variable filter from a topology-preserving transform. * Based on a talk given by Ivan Cohen: https://www.youtube.com/watch?v=esjHXGPyrhg */ - const ALfloat g = std::tan(al::MathDefs<float>::Pi() * f0norm); - const ALfloat h = 1.0f / (1 + (g / Q_FACTOR) + (g * g)); + const ALfloat g{mCoeff}; + const ALfloat gain{mGain}; + const ALfloat h{1.0f / (1.0f + (g/Q_FACTOR) + (g*g))}; + ALfloat s1{mS1}; + ALfloat s2{mS2}; for(size_t i{0u};i < numInput;i++) { - const ALfloat H = h * (samplesIn[i] - (1.0f / Q_FACTOR + g) * s1 - s2); - const ALfloat B = g * H + s1; - const ALfloat L = g * B + s2; + const ALfloat H{(samplesIn[i] - (1.0f/Q_FACTOR + g)*s1 - s2)*h}; + const ALfloat B{g*H + s1}; + const ALfloat L{g*B + s2}; - s1 = g * H + B; - s2 = g * B + L; + s1 = g*H + B; + s2 = g*B + L; // Apply peak and accumulate samples. - samplesOut[i] += B * fGain; + samplesOut[i] += B * gain; } + mS1 = s1; + mS2 = s2; } inline void clear() { - s1 = 0.0f; - s2 = 0.0f; + mS1 = 0.0f; + mS2 = 0.0f; } }; |