21 lines
484 B
C++
21 lines
484 B
C++
#include <psemek/audio/wave/triangle.hpp>
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#include <psemek/audio/wave/generator.hpp>
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#include <psemek/audio/detail/oscillator.hpp>
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#include <cmath>
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namespace psemek::audio
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{
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stream_ptr triangle_wave(float frequency)
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{
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auto func = [o = oscillator{frequency}]() mutable {
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auto const z = o.next();
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float const t = 0.5f * std::atan2(z.imag(), z.real()) / (math::pi) + 0.5f;
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return 4.f * std::abs(t - std::floor(t + 0.5f)) - 1.f;
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};
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return make_generator(func);
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}
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}
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