mirror of
https://github.com/KolibriOS/kolibrios.git
synced 2024-12-15 19:33:59 +03:00
127b85086b
- Added sound! - Added Linux makefile - Added _KOLIBRI definition - Removed not working parameters from --help in KolibriOS git-svn-id: svn://kolibrios.org@8645 a494cfbc-eb01-0410-851d-a64ba20cac60
125 lines
3.3 KiB
C
125 lines
3.3 KiB
C
/*
|
|
SDL_mixer: An audio mixer library based on the SDL library
|
|
Copyright (C) 1997-2012 Sam Lantinga <slouken@libsdl.org>
|
|
|
|
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.
|
|
|
|
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:
|
|
|
|
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.
|
|
|
|
This file by Ryan C. Gordon (icculus@icculus.org)
|
|
|
|
These are some helper functions for the internal mixer special effects.
|
|
*/
|
|
|
|
/* $Id$ */
|
|
|
|
|
|
/* ------ These are used internally only. Don't touch. ------ */
|
|
|
|
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include "SDL_mixer.h"
|
|
|
|
#define __MIX_INTERNAL_EFFECT__
|
|
#include "effects_internal.h"
|
|
|
|
/* Should we favor speed over memory usage and/or quality of output? */
|
|
int _Mix_effects_max_speed = 0;
|
|
|
|
|
|
void _Mix_InitEffects(void)
|
|
{
|
|
_Mix_effects_max_speed = (SDL_getenv(MIX_EFFECTSMAXSPEED) != NULL);
|
|
}
|
|
|
|
void _Mix_DeinitEffects(void)
|
|
{
|
|
_Eff_PositionDeinit();
|
|
}
|
|
|
|
|
|
void *_Eff_volume_table = NULL;
|
|
|
|
|
|
/* Build the volume table for Uint8-format samples.
|
|
*
|
|
* Each column of the table is a possible sample, while each row of the
|
|
* table is a volume. Volume is a Uint8, where 0 is silence and 255 is full
|
|
* volume. So _Eff_volume_table[128][mysample] would be the value of
|
|
* mysample, at half volume.
|
|
*/
|
|
void *_Eff_build_volume_table_u8(void)
|
|
{
|
|
int volume;
|
|
int sample;
|
|
Uint8 *rc;
|
|
|
|
if (!_Mix_effects_max_speed) {
|
|
return(NULL);
|
|
}
|
|
|
|
if (!_Eff_volume_table) {
|
|
rc = SDL_malloc(256 * 256);
|
|
if (rc) {
|
|
_Eff_volume_table = (void *) rc;
|
|
for (volume = 0; volume < 256; volume++) {
|
|
for (sample = -128; sample < 128; sample ++) {
|
|
*rc = (Uint8)(((float) sample) * ((float) volume / 255.0))
|
|
+ 128;
|
|
rc++;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return(_Eff_volume_table);
|
|
}
|
|
|
|
|
|
/* Build the volume table for Sint8-format samples.
|
|
*
|
|
* Each column of the table is a possible sample, while each row of the
|
|
* table is a volume. Volume is a Uint8, where 0 is silence and 255 is full
|
|
* volume. So _Eff_volume_table[128][mysample+128] would be the value of
|
|
* mysample, at half volume.
|
|
*/
|
|
void *_Eff_build_volume_table_s8(void)
|
|
{
|
|
int volume;
|
|
int sample;
|
|
Sint8 *rc;
|
|
|
|
if (!_Eff_volume_table) {
|
|
rc = SDL_malloc(256 * 256);
|
|
if (rc) {
|
|
_Eff_volume_table = (void *) rc;
|
|
for (volume = 0; volume < 256; volume++) {
|
|
for (sample = -128; sample < 128; sample ++) {
|
|
*rc = (Sint8)(((float) sample) * ((float) volume / 255.0));
|
|
rc++;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return(_Eff_volume_table);
|
|
}
|
|
|
|
|
|
/* end of effects.c ... */
|
|
|