/*
An LV2 plugin representing a simple mono amplifier.
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 "math_func.h"
#define AMP_GAIN 0
#define AMP_INPUT 1
#define AMP_OUTPUT 2
typedef struct {
const float* gain;
const float* input;
float* output;
} Amp;
static void
cleanup(LV2_Handle instance)
{
free(instance);
}
static void
connect_port(LV2_Handle instance,
uint32_t port,
void* data)
{
Amp* plugin = (Amp*)instance;
switch (port) {
case AMP_GAIN:
plugin->gain = data;
break;
case AMP_INPUT:
plugin->input = data;
break;
case AMP_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)
{
Amp* plugin = (Amp*)malloc(sizeof(Amp));
return (LV2_Handle)plugin;
}
static void
runAmp_gaia_oa(LV2_Handle instance,
uint32_t sample_count)
{
Amp* plugin = (Amp*)instance;
/* Gain (dB) */
const float* gain = plugin->gain;
/* Input */
const float* input = plugin->input;
/* Output */
float* output = plugin->output;
float gn;
float in;
float scale;
for (uint32_t s = 0; s < sample_count; ++s) {
gn = gain[s];
in = input[s];
scale = (float)EXPF(M_LN10 * gn * 0.05f);
output[s] = scale * in;
}
}
static void
runAmp_gcia_oa(LV2_Handle instance,
uint32_t sample_count)
{
Amp* plugin = (Amp*)instance;
/* Gain (dB) */
const float gain = *(plugin->gain);
/* Input */
const float* input = plugin->input;
/* Output */
float* output = plugin->output;
float in;
float scale = (float)EXPF(M_LN10 * gain * 0.05f);
for (uint32_t s = 0; s < sample_count; s++) {
in = input[s];
output[s] = scale * in;
}
}
static const LV2_Descriptor descriptor = {
"http://drobilla.net/plugins/blip/amp",
instantiate,
connect_port,
NULL,
runAmp_gcia_oa,
NULL,
cleanup,
NULL,
};
LV2_SYMBOL_EXPORT const LV2_Descriptor*
lv2_descriptor(uint32_t index)
{
switch (index) {
case 0: return &descriptor;
default: return NULL;
}
}