effect_position.c
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SDL_mixer: An audio mixer library based on the SDL library
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Copyright (C) 1997-2009 Sam Lantinga
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This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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This file by Ryan C. Gordon (icculus@icculus.org)
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These are some internally supported special effects that use SDL_mixer's
effect callback API. They are meant for speed over quality. :)
*/
/* $Id$ */
#include <stdio.h>
#include <stdlib.h>
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#include <string.h>
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#include "SDL.h"
#include "SDL_mixer.h"
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#include "SDL_endian.h"
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#define __MIX_INTERNAL_EFFECT__
#include "effects_internal.h"
/* profile code:
#include <sys/time.h>
#include <unistd.h>
struct timeval tv1;
struct timeval tv2;
gettimeofday(&tv1, NULL);
... do your thing here ...
gettimeofday(&tv2, NULL);
printf("%ld\n", tv2.tv_usec - tv1.tv_usec);
*/
/*
* Positional effects...panning, distance attenuation, etc.
*/
typedef struct _Eff_positionargs
{
volatile float left_f;
volatile float right_f;
volatile Uint8 left_u8;
volatile Uint8 right_u8;
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volatile float left_rear_f;
volatile float right_rear_f;
volatile float center_f;
volatile float lfe_f;
volatile Uint8 left_rear_u8;
volatile Uint8 right_rear_u8;
volatile Uint8 center_u8;
volatile Uint8 lfe_u8;
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volatile float distance_f;
volatile Uint8 distance_u8;
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volatile Sint16 room_angle;
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volatile int in_use;
volatile int channels;
} position_args;
static position_args **pos_args_array = NULL;
static position_args *pos_args_global = NULL;
static int position_channels = 0;
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void _Eff_PositionDeinit(void)
{
int i;
for (i = 0; i < position_channels; i++) {
free(pos_args_array[i]);
}
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position_channels = 0;
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free(pos_args_global);
pos_args_global = NULL;
free(pos_args_array);
pos_args_array = NULL;
}
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/* This just frees up the callback-specific data. */
static void _Eff_PositionDone(int channel, void *udata)
{
if (channel < 0) {
if (pos_args_global != NULL) {
free(pos_args_global);
pos_args_global = NULL;
}
}
else if (pos_args_array[channel] != NULL) {
free(pos_args_array[channel]);
pos_args_array[channel] = NULL;
}
}
static void _Eff_position_u8(int chan, void *stream, int len, void *udata)
{
volatile position_args *args = (volatile position_args *) udata;
Uint8 *ptr = (Uint8 *) stream;
int i;
/*
* if there's only a mono channnel (the only way we wouldn't have
* a len divisible by 2 here), then left_f and right_f are always
* 1.0, and are therefore throwaways.
*/
if (len % sizeof (Uint16) != 0) {
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*ptr = (Uint8) (((float) *ptr) * args->distance_f);
ptr++;
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len--;
}
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if (args->room_angle == 0)
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for (i = 0; i < len; i += sizeof (Uint8) * 2) {
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/* must adjust the sample so that 0 is the center */
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_f) * args->distance_f) + 128);
ptr++;
}
else for (i = 0; i < len; i += sizeof (Uint8) * 2) {
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/* must adjust the sample so that 0 is the center */
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_f) * args->distance_f) + 128);
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ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_f) * args->distance_f) + 128);
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ptr++;
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static void _Eff_position_u8_c4(int chan, void *stream, int len, void *udata)
{
volatile position_args *args = (volatile position_args *) udata;
Uint8 *ptr = (Uint8 *) stream;
int i;
/*
* if there's only a mono channnel (the only way we wouldn't have
* a len divisible by 2 here), then left_f and right_f are always
* 1.0, and are therefore throwaways.
*/
if (len % sizeof (Uint16) != 0) {
*ptr = (Uint8) (((float) *ptr) * args->distance_f);
ptr++;
len--;
}
if (args->room_angle == 0)
for (i = 0; i < len; i += sizeof (Uint8) * 6) {
/* must adjust the sample so that 0 is the center */
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_rear_f) * args->distance_f) + 128);
ptr++;
}
else if (args->room_angle == 90)
for (i = 0; i < len; i += sizeof (Uint8) * 6) {
/* must adjust the sample so that 0 is the center */
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_rear_f) * args->distance_f) + 128);
ptr++;
}
else if (args->room_angle == 180)
for (i = 0; i < len; i += sizeof (Uint8) * 6) {
/* must adjust the sample so that 0 is the center */
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_f) * args->distance_f) + 128);
ptr++;
}
else if (args->room_angle == 270)
for (i = 0; i < len; i += sizeof (Uint8) * 6) {
/* must adjust the sample so that 0 is the center */
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_f) * args->distance_f) + 128);
ptr++;
}
}
static void _Eff_position_u8_c6(int chan, void *stream, int len, void *udata)
{
volatile position_args *args = (volatile position_args *) udata;
Uint8 *ptr = (Uint8 *) stream;
int i;
/*
* if there's only a mono channnel (the only way we wouldn't have
* a len divisible by 2 here), then left_f and right_f are always
* 1.0, and are therefore throwaways.
*/
if (len % sizeof (Uint16) != 0) {
*ptr = (Uint8) (((float) *ptr) * args->distance_f);
ptr++;
len--;
}
if (args->room_angle == 0)
for (i = 0; i < len; i += sizeof (Uint8) * 6) {
/* must adjust the sample so that 0 is the center */
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->center_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->lfe_f) * args->distance_f) + 128);
ptr++;
}
else if (args->room_angle == 90)
for (i = 0; i < len; i += sizeof (Uint8) * 6) {
/* must adjust the sample so that 0 is the center */
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_rear_f) * args->distance_f/2) + 128)
+ (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_f) * args->distance_f/2) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->lfe_f) * args->distance_f) + 128);
ptr++;
}
else if (args->room_angle == 180)
for (i = 0; i < len; i += sizeof (Uint8) * 6) {
/* must adjust the sample so that 0 is the center */
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_rear_f) * args->distance_f/2) + 128)
+ (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_rear_f) * args->distance_f/2) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->lfe_f) * args->distance_f) + 128);
ptr++;
}
else if (args->room_angle == 270)
for (i = 0; i < len; i += sizeof (Uint8) * 6) {
/* must adjust the sample so that 0 is the center */
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_rear_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->right_f) * args->distance_f) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_f) * args->distance_f/2) + 128)
+ (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->left_rear_f) * args->distance_f/2) + 128);
ptr++;
*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
* args->lfe_f) * args->distance_f) + 128);
ptr++;
}
}
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/*
* This one runs about 10.1 times faster than the non-table version, with
* no loss in quality. It does, however, require 64k of memory for the
* lookup table. Also, this will only update position information once per
* call; the non-table version always checks the arguments for each sample,
* in case the user has called Mix_SetPanning() or whatnot again while this
* callback is running.
*/
static void _Eff_position_table_u8(int chan, void *stream, int len, void *udata)
{
volatile position_args *args = (volatile position_args *) udata;
Uint8 *ptr = (Uint8 *) stream;
Uint32 *p;
int i;
Uint8 *l = ((Uint8 *) _Eff_volume_table) + (256 * args->left_u8);
Uint8 *r = ((Uint8 *) _Eff_volume_table) + (256 * args->right_u8);
Uint8 *d = ((Uint8 *) _Eff_volume_table) + (256 * args->distance_u8);
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if (args->room_angle == 180) {
Uint8 *temp = l;
l = r;
r = temp;
}
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/*
* if there's only a mono channnel, then l[] and r[] are always
* volume 255, and are therefore throwaways. Still, we have to
* be sure not to overrun the audio buffer...
*/
while (len % sizeof (Uint32) != 0) {
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*ptr = d[l[*ptr]];
ptr++;
if (args->channels > 1) {
*ptr = d[r[*ptr]];
ptr++;
}
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len -= args->channels;
}
p = (Uint32 *) ptr;
for (i = 0; i < len; i += sizeof (Uint32)) {
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#if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
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*p = (d[l[(*p & 0xFF000000) >> 24]] << 24) |
(d[r[(*p & 0x00FF0000) >> 16]] << 16) |
(d[l[(*p & 0x0000FF00) >> 8]] << 8) |
(d[r[(*p & 0x000000FF) ]] ) ;
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*p = (d[r[(*p & 0xFF000000) >> 24]] << 24) |
(d[l[(*p & 0x00FF0000) >> 16]] << 16) |
(d[r[(*p & 0x0000FF00) >> 8]] << 8) |
(d[l[(*p & 0x000000FF) ]] ) ;
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++p;
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}
}
static void _Eff_position_s8(int chan, void *stream, int len, void *udata)
{
volatile position_args *args = (volatile position_args *) udata;
Sint8 *ptr = (Sint8 *) stream;
int i;
/*
* if there's only a mono channnel (the only way we wouldn't have
* a len divisible by 2 here), then left_f and right_f are always
* 1.0, and are therefore throwaways.
*/
if (len % sizeof (Sint16) != 0) {
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*ptr = (Sint8) (((float) *ptr) * args->distance_f);
ptr++;
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len--;
}
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if (args->room_angle == 180)
for (i = 0; i < len; i += sizeof (Sint8) * 2) {
*ptr = (Sint8)((((float) *ptr) * args->right_f) * args->distance_f);
ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_f) * args->distance_f);
ptr++;
}
else
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for (i = 0; i < len; i += sizeof (Sint8) * 2) {
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*ptr = (Sint8)((((float) *ptr) * args->left_f) * args->distance_f);
ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_f) * args->distance_f);
ptr++;
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static void _Eff_position_s8_c4(int chan, void *stream, int len, void *udata)
{
volatile position_args *args = (volatile position_args *) udata;
Sint8 *ptr = (Sint8 *) stream;
int i;
/*
* if there's only a mono channnel (the only way we wouldn't have
* a len divisible by 2 here), then left_f and right_f are always
* 1.0, and are therefore throwaways.
*/
if (len % sizeof (Sint16) != 0) {
*ptr = (Sint8) (((float) *ptr) * args->distance_f);
ptr++;
len--;
}
for (i = 0; i < len; i += sizeof (Sint8) * 4) {
switch (args->room_angle) {
case 0:
*ptr = (Sint8)((((float) *ptr) * args->left_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_rear_f) * args->distance_f); ptr++;
break;
case 90:
*ptr = (Sint8)((((float) *ptr) * args->right_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_rear_f) * args->distance_f); ptr++;
break;
case 180:
*ptr = (Sint8)((((float) *ptr) * args->right_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_f) * args->distance_f); ptr++;
break;
case 270:
*ptr = (Sint8)((((float) *ptr) * args->left_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_f) * args->distance_f); ptr++;
break;
}
}
}
static void _Eff_position_s8_c6(int chan, void *stream, int len, void *udata)
{
volatile position_args *args = (volatile position_args *) udata;
Sint8 *ptr = (Sint8 *) stream;
int i;
/*
* if there's only a mono channnel (the only way we wouldn't have
* a len divisible by 2 here), then left_f and right_f are always
* 1.0, and are therefore throwaways.
*/
if (len % sizeof (Sint16) != 0) {
*ptr = (Sint8) (((float) *ptr) * args->distance_f);
ptr++;
len--;
}
for (i = 0; i < len; i += sizeof (Sint8) * 6) {
switch (args->room_angle) {
case 0:
*ptr = (Sint8)((((float) *ptr) * args->left_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->center_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->lfe_f) * args->distance_f); ptr++;
break;
case 90:
*ptr = (Sint8)((((float) *ptr) * args->right_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_rear_f) * args->distance_f / 2)
+ (Sint8)((((float) *ptr) * args->right_f) * args->distance_f / 2); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->lfe_f) * args->distance_f); ptr++;
break;
case 180:
*ptr = (Sint8)((((float) *ptr) * args->right_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_rear_f) * args->distance_f / 2)
+ (Sint8)((((float) *ptr) * args->left_rear_f) * args->distance_f / 2); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->lfe_f) * args->distance_f); ptr++;
break;
case 270:
*ptr = (Sint8)((((float) *ptr) * args->left_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_rear_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->right_f) * args->distance_f); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->left_f) * args->distance_f / 2)
+ (Sint8)((((float) *ptr) * args->left_rear_f) * args->distance_f / 2); ptr++;
*ptr = (Sint8)((((float) *ptr) * args->lfe_f) * args->distance_f); ptr++;
break;
}
}
}
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/*
* This one runs about 10.1 times faster than the non-table version, with
* no loss in quality. It does, however, require 64k of memory for the
* lookup table. Also, this will only update position information once per
* call; the non-table version always checks the arguments for each sample,
* in case the user has called Mix_SetPanning() or whatnot again while this
* callback is running.
*/
static void _Eff_position_table_s8(int chan, void *stream, int len, void *udata)
{
volatile position_args *args = (volatile position_args *) udata;
Sint8 *ptr = (Sint8 *) stream;
Uint32 *p;
int i;
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Sint8 *l = ((Sint8 *) _Eff_volume_table) + (256 * args->left_u8);
Sint8 *r = ((Sint8 *) _Eff_volume_table) + (256 * args->right_u8);
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Sint8 *d = ((Sint8 *) _Eff_volume_table) + (256 * args->distance_u8);
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if (args->room_angle == 180) {
Sint8 *temp = l;
l = r;
r = temp;
}
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while (len % sizeof (Uint32) != 0) {
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*ptr = d[l[*ptr]];
ptr++;
if (args->channels > 1) {
*ptr = d[r[*ptr]];
ptr++;
}
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len -= args->channels;
}
p = (Uint32 *) ptr;
for (i = 0; i < len; i += sizeof (Uint32)) {
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#if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
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*p = (d[l[((Sint16)(Sint8)((*p & 0xFF000000) >> 24))+128]] << 24) |
(d[r[((Sint16)(Sint8)((*p & 0x00FF0000) >> 16))+128]] << 16) |
(d[l[((Sint16)(Sint8)((*p & 0x0000FF00) >> 8))+128]] << 8) |
(d[r[((Sint16)(Sint8)((*p & 0x000000FF) ))+128]] ) ;
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*p = (d[r[((Sint16)(Sint8)((*p & 0xFF000000) >> 24))+128]] << 24) |
(d[l[((Sint16)(Sint8)((*p & 0x00FF0000) >> 16))+128]] << 16) |
(d[r[((Sint16)(Sint8)((*p & 0x0000FF00) >> 8))+128]] << 8) |
(d[l[((Sint16)(Sint8)((*p & 0x000000FF) ))+128]] ) ;
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++p;
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}
}
/* !!! FIXME : Optimize the code for 16-bit samples? */
static void _Eff_position_u16lsb(int chan, void *stream, int len, void *udata)
{
volatile position_args *args = (volatile position_args *) udata;
Uint16 *ptr = (Uint16 *) stream;
int i;
for (i = 0; i < len; i += sizeof (Uint16) * 2) {
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Sint16 sampl = (Sint16) (SDL_SwapLE16(*(ptr+0)) - 32768);
Sint16 sampr = (Sint16) (SDL_SwapLE16(*(ptr+1)) - 32768);
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Uint16 swapl = (Uint16) ((Sint16) (((float) sampl * args->left_f)
* args->distance_f) + 32768);
Uint16 swapr = (Uint16) ((Sint16) (((float) sampr * args->right_f)
* args->distance_f) + 32768);
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if (args->room_angle == 180) {
*(ptr++) = (Uint16) SDL_SwapLE16(swapr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapl);
}
else {
*(ptr++) = (Uint16) SDL_SwapLE16(swapl);
*(ptr++) = (Uint16) SDL_SwapLE16(swapr);
}
}
}
static void _Eff_position_u16lsb_c4(int chan, void *stream, int len, void *udata)
{
volatile position_args *args = (volatile position_args *) udata;
Uint16 *ptr = (Uint16 *) stream;
int i;
for (i = 0; i < len; i += sizeof (Uint16) * 4) {
Sint16 sampl = (Sint16) (SDL_SwapLE16(*(ptr+0)) - 32768);
Sint16 sampr = (Sint16) (SDL_SwapLE16(*(ptr+1)) - 32768);
Sint16 samplr = (Sint16) (SDL_SwapLE16(*(ptr+2)) - 32768);
Sint16 samprr = (Sint16) (SDL_SwapLE16(*(ptr+3)) - 32768);
Uint16 swapl = (Uint16) ((Sint16) (((float) sampl * args->left_f)
* args->distance_f) + 32768);
Uint16 swapr = (Uint16) ((Sint16) (((float) sampr * args->right_f)
* args->distance_f) + 32768);
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Uint16 swaplr = (Uint16) ((Sint16) (((float) samplr * args->left_rear_f)
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* args->distance_f) + 32768);
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Uint16 swaprr = (Uint16) ((Sint16) (((float) samprr * args->right_rear_f)
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* args->distance_f) + 32768);
switch (args->room_angle) {
case 0:
*(ptr++) = (Uint16) SDL_SwapLE16(swapl);
*(ptr++) = (Uint16) SDL_SwapLE16(swapr);
*(ptr++) = (Uint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapLE16(swaprr);
break;
case 90:
*(ptr++) = (Uint16) SDL_SwapLE16(swapr);
*(ptr++) = (Uint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapl);
*(ptr++) = (Uint16) SDL_SwapLE16(swaplr);
break;
case 180:
*(ptr++) = (Uint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapl);
break;
case 270:
*(ptr++) = (Uint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapl);
*(ptr++) = (Uint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapr);
break;
}
}
}
static void _Eff_position_u16lsb_c6(int chan, void *stream, int len, void *udata)
{
volatile position_args *args = (volatile position_args *) udata;
Uint16 *ptr = (Uint16 *) stream;
int i;
for (i = 0; i < len; i += sizeof (Uint16) * 6) {
Sint16 sampl = (Sint16) (SDL_SwapLE16(*(ptr+0)) - 32768);
Sint16 sampr = (Sint16) (SDL_SwapLE16(*(ptr+1)) - 32768);
Sint16 samplr = (Sint16) (SDL_SwapLE16(*(ptr+2)) - 32768);
Sint16 samprr = (Sint16) (SDL_SwapLE16(*(ptr+3)) - 32768);
Sint16 sampce = (Sint16) (SDL_SwapLE16(*(ptr+4)) - 32768);
Sint16 sampwf = (Sint16) (SDL_SwapLE16(*(ptr+5)) - 32768);
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Uint16 swapl = (Uint16) ((Sint16) (((float) sampl * args->left_f)
* args->distance_f) + 32768);
Uint16 swapr = (Uint16) ((Sint16) (((float) sampr * args->right_f)
* args->distance_f) + 32768);
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Uint16 swaplr = (Uint16) ((Sint16) (((float) samplr * args->left_rear_f)
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* args->distance_f) + 32768);
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Uint16 swaprr = (Uint16) ((Sint16) (((float) samprr * args->right_rear_f)
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* args->distance_f) + 32768);
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Uint16 swapce = (Uint16) ((Sint16) (((float) sampce * args->center_f)
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* args->distance_f) + 32768);
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Uint16 swapwf = (Uint16) ((Sint16) (((float) sampwf * args->lfe_f)
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* args->distance_f) + 32768);
switch (args->room_angle) {
case 0:
*(ptr++) = (Uint16) SDL_SwapLE16(swapl);
*(ptr++) = (Uint16) SDL_SwapLE16(swapr);
*(ptr++) = (Uint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapce);
*(ptr++) = (Uint16) SDL_SwapLE16(swapwf);
break;
case 90:
*(ptr++) = (Uint16) SDL_SwapLE16(swapr);
*(ptr++) = (Uint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapl);
*(ptr++) = (Uint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapr)/2 + (Uint16) SDL_SwapLE16(swaprr)/2;
*(ptr++) = (Uint16) SDL_SwapLE16(swapwf);
break;
case 180:
*(ptr++) = (Uint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapl);
*(ptr++) = (Uint16) SDL_SwapLE16(swaprr)/2 + (Uint16) SDL_SwapLE16(swaplr)/2;
*(ptr++) = (Uint16) SDL_SwapLE16(swapwf);
break;
case 270:
*(ptr++) = (Uint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapl);
*(ptr++) = (Uint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapr);
*(ptr++) = (Uint16) SDL_SwapLE16(swapl)/2 + (Uint16) SDL_SwapLE16(swaplr)/2;
*(ptr++) = (Uint16) SDL_SwapLE16(swapwf);
break;
}
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}
}
static void _Eff_position_s16lsb(int chan, void *stream, int len, void *udata)
{
/* 16 signed bits (lsb) * 2 channels. */
volatile position_args *args = (volatile position_args *) udata;
Sint16 *ptr = (Sint16 *) stream;
int i;
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#if 0
if (len % (sizeof(Sint16) * 2)) {
fprintf(stderr,"Not an even number of frames! len=%d\n", len);
return;
}
#endif
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for (i = 0; i < len; i += sizeof (Sint16) * 2) {
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Sint16 swapl = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+0))) *
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args->left_f) * args->distance_f);
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Sint16 swapr = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+1))) *
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args->right_f) * args->distance_f);
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if (args->room_angle == 180) {
*(ptr++) = (Sint16) SDL_SwapLE16(swapr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapl);
}
else {
*(ptr++) = (Sint16) SDL_SwapLE16(swapl);
*(ptr++) = (Sint16) SDL_SwapLE16(swapr);
}
}
}
static void _Eff_position_s16lsb_c4(int chan, void *stream, int len, void *udata)
{
/* 16 signed bits (lsb) * 4 channels. */
volatile position_args *args = (volatile position_args *) udata;
Sint16 *ptr = (Sint16 *) stream;
int i;
for (i = 0; i < len; i += sizeof (Sint16) * 4) {
Sint16 swapl = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+0))) *
args->left_f) * args->distance_f);
Sint16 swapr = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+1))) *
args->right_f) * args->distance_f);
Sint16 swaplr = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+1))) *
args->left_rear_f) * args->distance_f);
Sint16 swaprr = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+2))) *
args->right_rear_f) * args->distance_f);
switch (args->room_angle) {
case 0:
*(ptr++) = (Sint16) SDL_SwapLE16(swapl);
*(ptr++) = (Sint16) SDL_SwapLE16(swapr);
*(ptr++) = (Sint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Sint16) SDL_SwapLE16(swaprr);
break;
case 90:
*(ptr++) = (Sint16) SDL_SwapLE16(swapr);
*(ptr++) = (Sint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapl);
*(ptr++) = (Sint16) SDL_SwapLE16(swaplr);
break;
case 180:
*(ptr++) = (Sint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Sint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapl);
break;
case 270:
*(ptr++) = (Sint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapl);
*(ptr++) = (Sint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapr);
break;
}
}
}
static void _Eff_position_s16lsb_c6(int chan, void *stream, int len, void *udata)
{
/* 16 signed bits (lsb) * 6 channels. */
volatile position_args *args = (volatile position_args *) udata;
Sint16 *ptr = (Sint16 *) stream;
int i;
for (i = 0; i < len; i += sizeof (Sint16) * 6) {
Sint16 swapl = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+0))) *
args->left_f) * args->distance_f);
Sint16 swapr = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+1))) *
args->right_f) * args->distance_f);
Sint16 swaplr = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+2))) *
args->left_rear_f) * args->distance_f);
Sint16 swaprr = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+3))) *
args->right_rear_f) * args->distance_f);
Sint16 swapce = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+4))) *
args->center_f) * args->distance_f);
Sint16 swapwf = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+5))) *
args->lfe_f) * args->distance_f);
switch (args->room_angle) {
case 0:
*(ptr++) = (Sint16) SDL_SwapLE16(swapl);
*(ptr++) = (Sint16) SDL_SwapLE16(swapr);
*(ptr++) = (Sint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Sint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapce);
*(ptr++) = (Sint16) SDL_SwapLE16(swapwf);
break;
case 90:
*(ptr++) = (Sint16) SDL_SwapLE16(swapr);
*(ptr++) = (Sint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapl);
*(ptr++) = (Sint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapr)/2 + (Sint16) SDL_SwapLE16(swaprr)/2;
*(ptr++) = (Sint16) SDL_SwapLE16(swapwf);
break;
case 180:
*(ptr++) = (Sint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Sint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapl);
*(ptr++) = (Sint16) SDL_SwapLE16(swaprr)/2 + (Sint16) SDL_SwapLE16(swaplr)/2;
*(ptr++) = (Sint16) SDL_SwapLE16(swapwf);
break;
case 270:
*(ptr++) = (Sint16) SDL_SwapLE16(swaplr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapl);
*(ptr++) = (Sint16) SDL_SwapLE16(swaprr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapr);
*(ptr++) = (Sint16) SDL_SwapLE16(swapl)/2 + (Sint16) SDL_SwapLE16(swaplr)/2;
*(ptr++) = (Sint16) SDL_SwapLE16(swapwf);
break;
}
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}
}
static void _Eff_position_u16msb(int chan, void *stream, int len, void *udata)
{
/* 16 signed bits (lsb) * 2 channels. */
volatile position_args *args = (volatile position_args *) udata;
Uint16 *ptr = (Uint16 *) stream;
int i;
for (i = 0; i < len; i += sizeof (Sint16) * 2) {
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Sint16 sampl = (Sint16) (SDL_SwapBE16(*(ptr+0)) - 32768);
Sint16 sampr = (Sint16) (SDL_SwapBE16(*(ptr+1)) - 32768);
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Uint16 swapl = (Uint16) ((Sint16) (((float) sampl * args->left_f)
* args->distance_f) + 32768);
Uint16 swapr = (Uint16) ((Sint16) (((float) sampr * args->right_f)
* args->distance_f) + 32768);
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if (args->room_angle == 180) {
*(ptr++) = (Uint16) SDL_SwapBE16(swapr);
*(ptr++) = (Uint16) SDL_SwapBE16(swapl);
}
else {
*(ptr++) = (Uint16) SDL_SwapBE16(swapl);
*(ptr++) = (Uint16) SDL_SwapBE16(swapr);
}
}
}
static void _Eff_position_u16msb_c4(int chan, void *stream, int len, void *udata)
{
/* 16 signed bits (lsb) * 4 channels. */
volatile position_args *args = (volatile position_args *) udata;
Uint16 *ptr = (Uint16 *) stream;
int i;
for (i = 0; i < len; i += sizeof (Sint16) * 4) {
Sint16 sampl = (Sint16) (SDL_SwapBE16(*(ptr+0)) - 32768);
Sint16 sampr = (Sint16) (SDL_SwapBE16(*(ptr+1)) - 32768);
Sint16 samplr = (Sint16) (SDL_SwapBE16(*(ptr+2)) - 32768);
Sint16 samprr = (Sint16) (SDL_SwapBE16(*(ptr+3)) - 32768);
Uint16 swapl = (Uint16) ((Sint16) (((float) sampl * args->left_f)
* args->distance_f) + 32768);
Uint16 swapr = (Uint16) ((Sint16) (((float) sampr * args->right_f)
* args->distance_f) + 32768);
Uint16 swaplr = (Uint16) ((Sint16) (((float) samplr * args->left_rear_f)
* args->distance_f) + 32768);
Uint16 swaprr = (Uint16) ((Sint16) (((float) samprr * args->right_rear_f)
* args->distance_f) + 32768);
switch (args->room_angle) {
case 0:
*(ptr++) = (Uint16) SDL_SwapBE16(swapl);
*(ptr++) = (Uint16) SDL_SwapBE16(swapr);
*(ptr++) = (Uint16) SDL_SwapBE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapBE16(swaprr);
break;
case 90:
*(ptr++) = (Uint16) SDL_SwapBE16(swapr);
*(ptr++) = (Uint16) SDL_SwapBE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapBE16(swapl);
*(ptr++) = (Uint16) SDL_SwapBE16(swaplr);
break;
case 180:
*(ptr++) = (Uint16) SDL_SwapBE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapBE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapBE16(swapr);
*(ptr++) = (Uint16) SDL_SwapBE16(swapl);
break;
case 270:
*(ptr++) = (Uint16) SDL_SwapBE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapBE16(swapl);
*(ptr++) = (Uint16) SDL_SwapBE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapBE16(swapr);
break;
}
}
}
static void _Eff_position_u16msb_c6(int chan, void *stream, int len, void *udata)
{
/* 16 signed bits (lsb) * 6 channels. */
volatile position_args *args = (volatile position_args *) udata;
Uint16 *ptr = (Uint16 *) stream;
int i;
for (i = 0; i < len; i += sizeof (Sint16) * 6) {
Sint16 sampl = (Sint16) (SDL_SwapBE16(*(ptr+0)) - 32768);
Sint16 sampr = (Sint16) (SDL_SwapBE16(*(ptr+1)) - 32768);
Sint16 samplr = (Sint16) (SDL_SwapBE16(*(ptr+2)) - 32768);
Sint16 samprr = (Sint16) (SDL_SwapBE16(*(ptr+3)) - 32768);
Sint16 sampce = (Sint16) (SDL_SwapBE16(*(ptr+4)) - 32768);
Sint16 sampwf = (Sint16) (SDL_SwapBE16(*(ptr+5)) - 32768);
Uint16 swapl = (Uint16) ((Sint16) (((float) sampl * args->left_f)
* args->distance_f) + 32768);
Uint16 swapr = (Uint16) ((Sint16) (((float) sampr * args->right_f)
* args->distance_f) + 32768);
Uint16 swaplr = (Uint16) ((Sint16) (((float) samplr * args->left_rear_f)
* args->distance_f) + 32768);
Uint16 swaprr = (Uint16) ((Sint16) (((float) samprr * args->right_rear_f)
* args->distance_f) + 32768);
Uint16 swapce = (Uint16) ((Sint16) (((float) sampce * args->center_f)
* args->distance_f) + 32768);
Uint16 swapwf = (Uint16) ((Sint16) (((float) sampwf * args->lfe_f)
* args->distance_f) + 32768);
switch (args->room_angle) {
case 0:
*(ptr++) = (Uint16) SDL_SwapBE16(swapl);
*(ptr++) = (Uint16) SDL_SwapBE16(swapr);
*(ptr++) = (Uint16) SDL_SwapBE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapBE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapBE16(swapce);
*(ptr++) = (Uint16) SDL_SwapBE16(swapwf);
break;
case 90:
*(ptr++) = (Uint16) SDL_SwapBE16(swapr);
*(ptr++) = (Uint16) SDL_SwapBE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapBE16(swapl);
*(ptr++) = (Uint16) SDL_SwapBE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapBE16(swapr)/2 + (Uint16) SDL_SwapBE16(swaprr)/2;
*(ptr++) = (Uint16) SDL_SwapBE16(swapwf);
break;
case 180:
*(ptr++) = (Uint16) SDL_SwapBE16(swaprr);
*(ptr++) = (Uint16) SDL_SwapBE16(swaplr);
*(ptr++) = (Uint16) SDL_SwapBE16(swapr);
*(ptr++) = (Uint16) SDL_SwapBE16(swapl);
*(ptr++) = (Uint16) SDL_SwapBE16(swaprr)/2 + (Uint16) SDL_SwapBE16(swaplr)/2;
*(ptr++) = (Uint16) SDL_SwapBE16(swapwf);
break;
case 270: