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Diffstat (limited to 'plugins/eg-synth.lv2/synth.c')
| -rw-r--r-- | plugins/eg-synth.lv2/synth.c | 171 |
1 files changed, 0 insertions, 171 deletions
diff --git a/plugins/eg-synth.lv2/synth.c b/plugins/eg-synth.lv2/synth.c deleted file mode 100644 index 758989b..0000000 --- a/plugins/eg-synth.lv2/synth.c +++ /dev/null @@ -1,171 +0,0 @@ -/* - 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. - - THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES - WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF - MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR - ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES - WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN - ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF - OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. -*/ - -/** - @file synth.c Implementation of the LV2 Sin Synth example plugin. - - This is a simple LV2 synthesis plugin that demonstrates how to receive MIDI - events and render audio in response to them. -*/ - -#include <math.h> -#include <stdlib.h> -#include <string.h> - -#include "lv2/lv2plug.in/ns/lv2core/lv2.h" - -#define SYNTH_URI "http://lv2plug.in/plugins/eg-synth" - -/** Port indices. */ -typedef enum { - SYNTH_FREQ = 0, - SYNTH_OUTPUT, -} PortIndex; - -/** Plugin instance. */ -typedef struct { - // Sample rate, necessary to generate sin wave in run() - double sample_rate; - - // Current wave phase - float phase; - - // Port buffers - const float* freq; - float* output; -} Synth; - -/** Create a new plugin instance. */ -static LV2_Handle -instantiate(const LV2_Descriptor* descriptor, - double rate, - const char* bundle_path, - const LV2_Feature* const* features) -{ - Synth* self = (Synth*)malloc(sizeof(Synth)); - if (self) { - // Store the sample rate so it is available in run() - self->sample_rate = rate; - } - return (LV2_Handle)self; -} - -/** Connect a port to a buffer (audio thread, must be RT safe). */ -static void -connect_port(LV2_Handle instance, - uint32_t port, - void* data) -{ - Synth* self = (Synth*)instance; - - switch ((PortIndex)port) { - case SYNTH_FREQ: - self->freq = (const float*)data; - break; - case SYNTH_OUTPUT: - self->output = (float*)data; - break; - } -} - -/** Initialise and prepare the plugin instance for running. */ -static void -activate(LV2_Handle instance) -{ - Synth* self = (Synth*)instance; - - // Initialize phase so we start at the beginning of the wave - self->phase = 0.0f; -} - -/** Process a block of audio (audio thread, must be RT safe). */ -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) { - self->phase = 0.0f; - } - } -} - -/** Finish running (counterpart to activate()). */ -static void -deactivate(LV2_Handle instance) -{ - /* Nothing to do here in this trivial mostly stateless plugin. */ -} - -/** Destroy a plugin instance (counterpart to instantiate()). */ -static void -cleanup(LV2_Handle instance) -{ - free(instance); -} - -/** Return extension data provided by the plugin. */ -static const void* -extension_data(const char* uri) -{ - return NULL; /* This plugin has no extension data. */ -} - -/** The LV2_Descriptor for this plugin. */ -static const LV2_Descriptor descriptor = { - SYNTH_URI, - instantiate, - connect_port, - activate, - run, - deactivate, - cleanup, - extension_data -}; - -/** Entry point, the host will call this function to access descriptors. */ -LV2_SYMBOL_EXPORT -const LV2_Descriptor* -lv2_descriptor(uint32_t index) -{ - switch (index) { - case 0: - return &descriptor; - default: - return NULL; - } -} |