30 lines
399 B
C++
30 lines
399 B
C++
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#pragma once
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#include <inttypes.h>
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struct Tone {
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uint32_t phase;
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uint16_t frequency;
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uint8_t amplitude;
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inline static int8_t sin_lookup[256];
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static void init();
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inline bool active() const {
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return amplitude > 0;
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}
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inline void update(uint32_t t) {
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phase += t * frequency;
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}
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inline int get() const {
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uint8_t id = phase >> 12;
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return (int)sin_lookup[id] * amplitude;
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}
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};
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