73 lines
2.0 KiB
C
73 lines
2.0 KiB
C
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/* FluidSynth - A Software Synthesizer
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*
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* Copyright (C) 2003 Peter Hanappe and others.
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Library General Public License
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* as published by the Free Software Foundation; either version 2 of
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* the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Library General Public License for more details.
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*
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* You should have received a copy of the GNU Library General Public
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* License along with this library; if not, write to the Free
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* Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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* 02110-1301, USA
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*/
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#ifndef _FLUID_LFO_H
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#define _FLUID_LFO_H
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#include "fluidsynth_priv.h"
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typedef struct _fluid_lfo_t fluid_lfo_t;
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struct _fluid_lfo_t {
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fluid_real_t val; /* the current value of the LFO */
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unsigned int delay; /* the delay of the lfo in samples */
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fluid_real_t increment; /* the lfo frequency is converted to a per-buffer increment */
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};
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static inline void
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fluid_lfo_reset(fluid_lfo_t* lfo)
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{
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lfo->val = 0.0f;
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}
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// These two cannot be inlined since they're used by event_dispatch
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void fluid_lfo_set_incr(fluid_lfo_t* lfo, fluid_real_t increment);
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void fluid_lfo_set_delay(fluid_lfo_t* lfo, unsigned int delay);
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static inline fluid_real_t
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fluid_lfo_get_val(fluid_lfo_t* lfo)
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{
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return lfo->val;
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}
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static inline void
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fluid_lfo_calc(fluid_lfo_t* lfo, unsigned int cur_delay)
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{
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if (cur_delay < lfo->delay)
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return;
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lfo->val += lfo->increment;
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if (lfo->val > (fluid_real_t) 1.0)
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{
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lfo->increment = -lfo->increment;
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lfo->val = (fluid_real_t) 2.0 - lfo->val;
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}
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else if (lfo->val < (fluid_real_t) -1.0)
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{
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lfo->increment = -lfo->increment;
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lfo->val = (fluid_real_t) -2.0 - lfo->val;
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}
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}
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#endif
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