effect_position.c
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SDL_mixer: An audio mixer library based on the SDL library
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Copyright (C) 1997-2017 Sam Lantinga <slouken@libsdl.org>
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This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
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Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
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1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
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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. :)
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*/
/* $Id$ */
#include <stdio.h>
#include <stdlib.h>
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#include <string.h>
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#include "SDL.h"
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#include "SDL_endian.h"
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#include "SDL_mixer.h"
#include "mixer.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;
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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++) {
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SDL_free(pos_args_array[i]);
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position_channels = 0;
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SDL_free(pos_args_global);
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pos_args_global = NULL;
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SDL_free(pos_args_array);
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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) {
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SDL_free(pos_args_global);
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pos_args_global = NULL;
}
}
else if (pos_args_array[channel] != NULL) {
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SDL_free(pos_args_array[channel]);
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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 == 180)
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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 */
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* 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++;
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*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 */
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* 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 */
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* 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 */
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* 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 */
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* 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 */
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->center_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* 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 */
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_rear_f) * args->distance_f/2) + 128)
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+ (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_f) * args->distance_f/2) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* 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 */
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_rear_f) * args->distance_f/2) + 128)
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+ (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_rear_f) * args->distance_f/2) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* 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 */
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_rear_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->right_f) * args->distance_f) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_f) * args->distance_f/2) + 128)
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+ (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* args->left_rear_f) * args->distance_f/2) + 128);
ptr++;
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*ptr = (Uint8) ((Sint8) ((((float) (Sint8) (*ptr - 128))
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* 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) {
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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++;
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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++;
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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++;
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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++;
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}
}
}
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++;
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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++;
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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++;
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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++;
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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);
565
if (args->room_angle == 180) {
566
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568
Sint8 *temp = l;
l = r;
r = temp;
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while (len % sizeof (Uint32) != 0) {
573
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*ptr = d[l[*ptr]];
ptr++;
if (args->channels > 1) {
*ptr = d[r[*ptr]];
ptr++;
}
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581
582
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584
len -= args->channels;
}
p = (Uint32 *) ptr;
for (i = 0; i < len; i += sizeof (Uint32)) {
585
#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]] ) ;
596
++p;
597
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603
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605
606
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609
610
611
}
}
/* !!! 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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626
627
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);
}
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631
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635
636
637
638
639
640
}
}
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);
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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);
646
Uint16 swaplr = (Uint16) ((Sint16) (((float) samplr * args->left_rear_f)
647
* args->distance_f) + 32768);
648
Uint16 swaprr = (Uint16) ((Sint16) (((float) samprr * args->right_rear_f)
649
650
* args->distance_f) + 32768);
651
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653
654
655
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661
662
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664
665
666
667
668
669
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671
672
673
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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;
}
677
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679
680
681
682
683
684
685
686
687
688
689
690
691
}
}
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);
697
Uint16 swaplr = (Uint16) ((Sint16) (((float) samplr * args->left_rear_f)
698
* args->distance_f) + 32768);
699
Uint16 swaprr = (Uint16) ((Sint16) (((float) samprr * args->right_rear_f)
700
* args->distance_f) + 32768);
701
Uint16 swapce = (Uint16) ((Sint16) (((float) sampce * args->center_f)
702
* args->distance_f) + 32768);
703
Uint16 swapwf = (Uint16) ((Sint16) (((float) sampwf * args->lfe_f)
704
705
* args->distance_f) + 32768);
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714
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720
721
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724
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729
730
731
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733
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736
737
738
739
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;
}
740
741
742
743
744
745
746
747
748
749
}
}
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;
750
751
#if 0
if (len % (sizeof(Sint16) * 2)) {
752
753
fprintf(stderr,"Not an even number of frames! len=%d\n", len);
return;
754
755
756
}
#endif
757
for (i = 0; i < len; i += sizeof (Sint16) * 2) {
758
Sint16 swapl = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+0))) *
759
args->left_f) * args->distance_f);
760
Sint16 swapr = (Sint16) ((((float) (Sint16) SDL_SwapLE16(*(ptr+1))) *
761
args->right_f) * args->distance_f);
762
763
764
765
766
767
768
769
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);
}
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
}
}
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);
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790
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792
793
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795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
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;
}
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
}
}
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);
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
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;
}
871
872
873
874
875
876
877
878
879
880
881
}
}
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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883
Sint16 sampl = (Sint16) (SDL_SwapBE16(*(ptr+0)) - 32768);
Sint16 sampr = (Sint16) (SDL_SwapBE16(*(ptr+1)) - 32768);
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889
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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892
893
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895
896
897
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);
}
898
899
900
901
902
903
904
905
906
907
908
909
910
911
}
}
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);
913
914
915
916
917
918
919
920
921
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);
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
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;
}
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}
}
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);
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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);
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);
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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;