From e550736dbb862d8333a4d7f2ede9804a3d48326c Mon Sep 17 00:00:00 2001 From: David Robillard Date: Mon, 3 Oct 2011 05:22:14 +0000 Subject: Add 'blip', an LV2 port of the LADSPA 'blop' collection. git-svn-id: http://svn.drobilla.net/lad/trunk/plugins/blip.lv2@3525 a436a847-0d15-0410-975c-d299462d15a1 --- src/triangle.c | 307 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 307 insertions(+) create mode 100644 src/triangle.c (limited to 'src/triangle.c') diff --git a/src/triangle.c b/src/triangle.c new file mode 100644 index 0000000..718369a --- /dev/null +++ b/src/triangle.c @@ -0,0 +1,307 @@ +/* + An LV2 plugin to generate a bandlimited slope-variable triangle waveform. + Copyright 2011 David Robillard + Copyright 2002 Mike Rawes + + This is free software: you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This software is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this software. If not, see . +*/ + +#include +#include "lv2/lv2plug.in/ns/lv2core/lv2.h" +#include "wavedata.h" + +#define TRIANGLE_FREQUENCY 0 +#define TRIANGLE_SLOPE 1 +#define TRIANGLE_OUTPUT 2 + +typedef struct { + float* frequency; + float* slope; + float* output; + float phase; + float min_slope; + float max_slope; + Wavedata wdat; +} Triangle; + +static void +connect_port(LV2_Handle instance, + uint32_t port, + void* data) +{ + Triangle* plugin = (Triangle*)instance; + + switch (port) { + case TRIANGLE_FREQUENCY: + plugin->frequency = data; + break; + case TRIANGLE_SLOPE: + plugin->slope = data; + break; + case TRIANGLE_OUTPUT: + plugin->output = data; + break; + } +} + +static LV2_Handle +instantiate(const LV2_Descriptor* descriptor, + double sample_rate, + const char* bundle_path, + const LV2_Feature* const* features) +{ + Triangle* plugin = (Triangle*)malloc(sizeof(Triangle)); + + if (wavedata_load(&plugin->wdat, BLOP_DLSYM_PARABOLA, sample_rate)) { + free(plugin); + return 0; + } + + plugin->min_slope = 2.0f / plugin->wdat.sample_rate; + plugin->max_slope = 1.0f - plugin->min_slope; + + return (LV2_Handle)plugin; +} + +static void +cleanup(LV2_Handle instance) +{ + Triangle* plugin = (Triangle*)instance; + + wavedata_unload(&plugin->wdat); + free(instance); +} + +static void +activate(LV2_Handle instance) +{ + Triangle* plugin = (Triangle*)instance; + + plugin->phase = 0.0f; +} + +static void +runTriangle_fasa_oa(LV2_Handle instance, + uint32_t sample_count) +{ + Triangle* plugin = (Triangle*)instance; + + /* Frequency (array of float of length sample_count) */ + float* frequency = plugin->frequency; + + /* Slope (array of float of length sample_count) */ + float* slope = plugin->slope; + + /* Output (pointer to float value) */ + float* output = plugin->output; + + /* Instance data */ + Wavedata* wdat = &plugin->wdat; + float phase = plugin->phase; + float min_slope = plugin->min_slope; + float max_slope = plugin->max_slope; + + float freq; + float slp; + float phase_shift; + + for (uint32_t s = 0; s < sample_count; ++s) { + freq = frequency[s]; + slp = f_clip(slope[s], min_slope, max_slope); + phase_shift = slp * wdat->sample_rate; + + /* Lookup which table to use from frequency */ + wavedata_get_table(wdat, freq); + + /* Get samples from parabola and phase shifted inverted parabola, + and scale to compensate */ + output[s] = (wavedata_get_sample(wdat, phase) + - wavedata_get_sample(wdat, phase + phase_shift)) + / (8.0f * (slp - (slp * slp))); + + /* Update phase, wrapping if necessary */ + phase += wdat->frequency; + if (phase < 0.0f) { + phase += wdat->sample_rate; + } else if (phase > wdat->sample_rate) { + phase -= wdat->sample_rate; + } + } + plugin->phase = phase; +} + +static void +runTriangle_fasc_oa(LV2_Handle instance, + uint32_t sample_count) +{ + Triangle* plugin = (Triangle*)instance; + + /* Frequency (array of float of length sample_count) */ + float* frequency = plugin->frequency; + + /* Slope (float value) */ + float slope = *(plugin->slope); + + /* Output (pointer to float value) */ + float* output = plugin->output; + + /* Instance data */ + Wavedata* wdat = &plugin->wdat; + float phase = plugin->phase; + float min_slope = plugin->min_slope; + float max_slope = plugin->max_slope; + + float freq; + float phase_shift; + float scale; + + slope = f_clip(slope, min_slope, max_slope); + scale = 1.0f / (8.0f * (slope - (slope * slope))); + phase_shift = slope * wdat->sample_rate; + + for (uint32_t s = 0; s < sample_count; ++s) { + freq = frequency[s]; + + /* Lookup which table to use from frequency */ + wavedata_get_table(wdat, freq); + + /* Get samples from parabola and phase shifted inverted parabola, + and scale to compensate */ + output[s] = (wavedata_get_sample(wdat, phase) + - wavedata_get_sample(wdat, phase + phase_shift)) * scale; + + /* Update phase, wrapping if necessary */ + phase += wdat->frequency; + if (phase < 0.0f) { + phase += wdat->sample_rate; + } else if (phase > wdat->sample_rate) { + phase -= wdat->sample_rate; + } + } + plugin->phase = phase; +} + +static void +runTriangle_fcsa_oa(LV2_Handle instance, + uint32_t sample_count) +{ + Triangle* plugin = (Triangle*)instance; + + /* Frequency (float value) */ + float frequency = *(plugin->frequency); + + /* Slope (array of float of length sample_count) */ + float* slope = plugin->slope; + + /* Output (pointer to float value) */ + float* output = plugin->output; + + /* Instance data */ + Wavedata* wdat = &plugin->wdat; + float phase = plugin->phase; + float min_slope = plugin->min_slope; + float max_slope = plugin->max_slope; + + float slp; + float phase_shift; + + wavedata_get_table(wdat, frequency); + + for (uint32_t s = 0; s < sample_count; ++s) { + slp = f_clip(slope[s], min_slope, max_slope); + phase_shift = slp * wdat->sample_rate; + + /* Get samples from parabola and phase shifted inverted parabola, + and scale to compensate */ + output[s] = (wavedata_get_sample(wdat, phase) + - wavedata_get_sample(wdat, phase + phase_shift)) + / (8.0f * (slp - (slp * slp))); + + /* Update phase, wrapping if necessary */ + phase += wdat->frequency; + if (phase < 0.0f) { + phase += wdat->sample_rate; + } else if (phase > wdat->sample_rate) { + phase -= wdat->sample_rate; + } + } + plugin->phase = phase; +} + +static void +runTriangle_fcsc_oa(LV2_Handle instance, + uint32_t sample_count) +{ + Triangle* plugin = (Triangle*)instance; + + /* Frequency (float value) */ + float frequency = *(plugin->frequency); + + /* Slope (float value) */ + float slope = *(plugin->slope); + + /* Output (pointer to float value) */ + float* output = plugin->output; + + /* Instance data */ + Wavedata* wdat = &plugin->wdat; + float phase = plugin->phase; + float min_slope = plugin->min_slope; + float max_slope = plugin->max_slope; + + float scale; + float phase_shift; + + slope = f_clip(slope, min_slope, max_slope); + scale = 1.0f / (8.0f * (slope - (slope * slope))); + phase_shift = slope * wdat->sample_rate; + + wavedata_get_table(wdat, frequency); + + for (uint32_t s = 0; s < sample_count; ++s) { + /* Get samples from parabola and phase shifted inverted parabola, + and scale to compensate */ + output[s] = (wavedata_get_sample(wdat, phase) + - wavedata_get_sample(wdat, phase + phase_shift)) * scale; + + /* Update phase, wrapping if necessary */ + phase += wdat->frequency; + if (phase < 0.0f) { + phase += wdat->sample_rate; + } else if (phase > wdat->sample_rate) { + phase -= wdat->sample_rate; + } + } + plugin->phase = phase; +} + +static const LV2_Descriptor descriptor = { + "http://drobilla.net/plugins/blip/triangle", + instantiate, + connect_port, + activate, + runTriangle_fcsc_oa, + NULL, + cleanup, + NULL, +}; + +LV2_SYMBOL_EXPORT const LV2_Descriptor* +lv2_descriptor(uint32_t index) +{ + switch (index) { + case 0: return &descriptor; + default: return NULL; + } +} -- cgit v1.2.1