diff options
| -rw-r--r-- | plugins/eg-synth.lv2/synth.c | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/plugins/eg-synth.lv2/synth.c b/plugins/eg-synth.lv2/synth.c index c607daa..f64741a 100644 --- a/plugins/eg-synth.lv2/synth.c +++ b/plugins/eg-synth.lv2/synth.c @@ -1,7 +1,7 @@ /* Copyright 2012 Harry van Haaren <harryhaaren@gmail.com> Copyright 2012 David Robillard <d@drobilla.net> - + Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies. @@ -40,7 +40,7 @@ typedef enum { typedef struct { // Sample rate, necessary to generate sin wave in run() double sample_rate; - + // Current wave phase float phase; @@ -58,10 +58,10 @@ instantiate(const LV2_Descriptor* descriptor, const LV2_Feature* const* features) { Synth* self = (Synth*)malloc(sizeof(Synth)); - + // Store the sample rate so it is available in run() self->sample_rate = rate; - + return (LV2_Handle)self; } @@ -98,26 +98,26 @@ static void run(LV2_Handle instance, uint32_t n_samples) { Synth* self = (Synth*)instance; - + const float PI = 3.1415; const float volume = 0.3; const float freq = *(self->freq); float* const output = self->output; - + float samples_per_cycle = self->sample_rate / freq; - + /* Calculate the phase offset per sample. Phase ranges from 0..1, so phase_increment is a floating point number such that we get "freq" number of cycles in "sample_rate" amount of samples. */ float phase_increment = (1.f / samples_per_cycle); - + for (uint32_t pos = 0; pos < n_samples; pos++) { - + /* Calculate the next sample. Phase ranges from 0..1, but sin() expects its input in radians, so we multiply by 2 PI to convert it. We also multiply by volume so it's not extremely loud. */ output[pos] = sin(self->phase * 2 * PI) * volume; - + /* Increment the phase so we generate the next sample */ self->phase += phase_increment; if (self->phase > 1.0f) { |