src/audio/gen.h


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// This file is part of the 64k demo project.
// It defines the procedural audio generation interface.
// Shared between the offline spectool and the runtime demo.

#pragma once
#include <vector>

struct NoteParams {
  float base_freq;
  float duration_sec;
  float amplitude;
  float attack_sec;
  float decay_sec; // Unused for now
  float vibrato_rate;
  float vibrato_depth;
  int num_harmonics;
  float harmonic_decay;
  float pitch_randomness;
  float amp_randomness;
};

// Generates a single note into a new spectrogram buffer
std::vector<float> generate_note_spectrogram(const NoteParams &params,
                                             int *out_num_frames);

// Pastes a source spectrogram into a destination spectrogram at a given frame
// offset Expands destination if necessary
void paste_spectrogram(std::vector<float> &dest_data, int *dest_num_frames,
                       const std::vector<float> &src_data, int src_num_frames,
                       int frame_offset);

// Post-processing effects
void apply_spectral_noise(std::vector<float> &data, int num_frames,
                          float amount);
void apply_spectral_lowpass(std::vector<float> &data, int num_frames,
                            float cutoff_ratio);
void apply_spectral_comb(std::vector<float> &data, int num_frames,
                         float period_bins, float depth);