mirror of
https://github.com/ZDoom/raze-gles.git
synced 2024-12-25 11:10:47 +00:00
112 lines
2.9 KiB
C
112 lines
2.9 KiB
C
/*
|
|
Copyright (C) 1994-1995 Apogee Software, Ltd.
|
|
|
|
This program is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU General Public License
|
|
as published by the Free Software Foundation; either version 2
|
|
of the License, or (at your option) any later version.
|
|
|
|
This program 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 General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
|
|
*/
|
|
/**********************************************************************
|
|
module: PITCH.C
|
|
|
|
author: James R. Dose
|
|
date: June 14, 1993
|
|
|
|
Routines for pitch scaling.
|
|
|
|
(c) Copyright 1993 James R. Dose. All Rights Reserved.
|
|
**********************************************************************/
|
|
|
|
#include <stdlib.h>
|
|
#include <math.h>
|
|
#include "pitch.h"
|
|
|
|
#define MAXDETUNE 50
|
|
|
|
static uint32_t PitchTable[ 12 ][ MAXDETUNE ];
|
|
static int32_t PITCH_Installed = 0;
|
|
|
|
|
|
/*---------------------------------------------------------------------
|
|
Function: PITCH_Init
|
|
|
|
Initializes pitch table.
|
|
---------------------------------------------------------------------*/
|
|
|
|
|
|
void PITCH_Init(void)
|
|
{
|
|
int32_t note;
|
|
int32_t detune;
|
|
|
|
if (!PITCH_Installed)
|
|
{
|
|
for (note = 0; note < 12; note++)
|
|
{
|
|
for (detune = 0; detune < MAXDETUNE; detune++)
|
|
{
|
|
PitchTable[ note ][ detune ] = 0x10000 *
|
|
pow(2, (note * MAXDETUNE + detune) / (12.0 * MAXDETUNE));
|
|
}
|
|
}
|
|
|
|
PITCH_Installed = 1;
|
|
}
|
|
}
|
|
|
|
|
|
/*---------------------------------------------------------------------
|
|
Function: PITCH_GetScale
|
|
|
|
Returns a fixed-point value to scale number the specified amount.
|
|
---------------------------------------------------------------------*/
|
|
|
|
uint32_t PITCH_GetScale(int32_t pitchoffset)
|
|
{
|
|
uint32_t scale;
|
|
int32_t octaveshift;
|
|
int32_t noteshift;
|
|
int32_t note;
|
|
int32_t detune;
|
|
|
|
if ( !PITCH_Installed )
|
|
PITCH_Init();
|
|
|
|
if (pitchoffset == 0)
|
|
return(PitchTable[ 0 ][ 0 ]);
|
|
|
|
noteshift = pitchoffset % 1200;
|
|
if (noteshift < 0)
|
|
noteshift += 1200;
|
|
|
|
note = noteshift / 100;
|
|
detune = (noteshift % 100) / (100 / MAXDETUNE);
|
|
octaveshift = (pitchoffset - noteshift) / 1200;
|
|
|
|
if (detune < 0)
|
|
{
|
|
detune += (100 / MAXDETUNE);
|
|
note--;
|
|
if (note < 0)
|
|
{
|
|
note += 12;
|
|
octaveshift--;
|
|
}
|
|
}
|
|
|
|
scale = PitchTable[ note ][ detune ];
|
|
|
|
return (octaveshift < 0) ? (scale >> -octaveshift) : (scale <<= octaveshift);
|
|
}
|
|
|