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#ifdef CONFIG_OSS_VMIX_FLOAT
/*
* Purpose: Application to local playback buffer import routine for vmix (FP)
*/
/*
*
* This file is part of Open Sound System.
*
* Copyright (C) 4Front Technologies 1996-2008.
*
* This this source file is released under GPL v2 license (no other versions).
* See the COPYING file included in the main directory of this source
* distribution for the license terms and conditions.
*
*/
/*
* Mixing function for virtual devices
*/
vmix_mixer_t *mixer = portc->mixer;
vmix_engine_t *eng = &mixer->play_engine;
dmap_t *dmap = audio_engines[portc->audio_dev]->dmap_out;
int frame_size;
int inptr, inmax;
int used_channels;
int i, ch, nch;
double vol;
/*
* Initial setup
*/
frame_size = sizeof (*inp);
inmax = dmap->bytes_in_use / frame_size;
inptr = portc->play_dma_pointer / frame_size;
inp = (BUFFER_TYPE) dmap->dmabuf;
used_channels = portc->channels;
if (used_channels > eng->channels)
used_channels = eng->channels;
/* ignored_channels = portc->channels - used_channels; */
/*
* Handle mono playback by playing the mono stream twice (for left and right ch)
*/
nch=used_channels;
if (nch<2)nch=2;
/*
* Do the mixing
*/
for (ch = 0; ch < nch; ch++)
{
int ip = inptr + (ch%used_channels);
double vu = portc->vu[ch % 2];
float *chbuf = eng->chbufs[ch+portc->play_choffs];
i = portc->volume[ch%2];
vol = vmix_db_table[i / 5];
vu = vu / 255.0;
for (i = 0; i < nsamples; i++)
{
double tmp;
#if 0 && defined(SINE_DEBUG)
if (ch > 1)
tmp = 0.0;
else
tmp = sine_table[sine_phase[ch]];
sine_phase[ch] = (sine_phase[ch] + 1) % SINE_SIZE;
#else
/*
* Convert the sample to right endianess.
*/
tmp = VMIX_BYTESWAP (inp[ip]);
tmp = tmp * range;
#endif
tmp = tmp * vol;
*chbuf++ += tmp;
ip = (ip + portc->channels) % inmax;
/* VU meter */
if (tmp < 0.0)
tmp = -tmp;
if (tmp > vu)
vu = tmp;
}
if (ch < 2)
{ /* Save left/right VU meters */
vu = vu * 255.0;
portc->vu[ch] = (int)vu;
}
}
/*
* Finally save the state variables
*/
portc->play_dma_pointer =
(portc->play_dma_pointer +
nsamples * frame_size * portc->channels) % dmap->bytes_in_use;
#else
#include "playmix_int.inc"
#endif
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