lilium-voyager/code/renderercommon/tr_noise.c
Zack Middleton c6e5f060fe Port Elite Force iorev2231 patch to latest ioq3
Port Thilo Schulz's Elite Force Holomatch patch to latest ioq3.
Patch for ioq3 svn r2231.

No support for OpenGL2 renderer yet.
2014-10-29 07:15:12 -05:00

100 lines
3 KiB
C

/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.
This file is part of Quake III Arena source code.
Quake III Arena source code 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.
Quake III Arena source code 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 Quake III Arena source code; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
===========================================================================
*/
// tr_noise.c
#include "tr_common.h"
#define NOISE_SIZE FUNCTABLE_SIZE
#define NOISE_MASK ( NOISE_SIZE - 1 )
#define VAL( a ) s_noise_perm[ ( a ) & ( NOISE_MASK )]
#define INDEX( x, y, z, t ) VAL( x + VAL( y + VAL( z + VAL( t ) ) ) )
static float s_noise_table[NOISE_SIZE];
static int s_noise_perm[NOISE_SIZE];
static int s_random[NOISE_SIZE];
static float GetNoiseValue( int x, int y, int z, int t )
{
int index = INDEX( ( int ) x, ( int ) y, ( int ) z, ( int ) t );
return s_noise_table[index];
}
void R_NoiseInit( void )
{
int i;
for ( i = 0; i < NOISE_SIZE; i++ )
{
s_noise_table[i] = ( float ) ( ( ( rand() / ( float ) RAND_MAX ) * 2.0 - 1.0 ) );
s_noise_perm[i] = ( unsigned char ) ( rand() / ( float ) RAND_MAX * 255 );
s_random[i] = rand() & 0x01;
}
}
float R_NoiseGet4f( float x, float y, float z, float t )
{
int i;
int ix, iy, iz, it;
float fx, fy, fz, ft;
float front[4];
float back[4];
float fvalue, bvalue, value[2], finalvalue;
ix = ( int ) floor( x );
fx = x - ix;
iy = ( int ) floor( y );
fy = y - iy;
iz = ( int ) floor( z );
fz = z - iz;
it = ( int ) floor( t );
ft = t - it;
for ( i = 0; i < 2; i++ )
{
front[0] = GetNoiseValue( ix, iy, iz, it + i );
front[1] = GetNoiseValue( ix+1, iy, iz, it + i );
front[2] = GetNoiseValue( ix, iy+1, iz, it + i );
front[3] = GetNoiseValue( ix+1, iy+1, iz, it + i );
back[0] = GetNoiseValue( ix, iy, iz + 1, it + i );
back[1] = GetNoiseValue( ix+1, iy, iz + 1, it + i );
back[2] = GetNoiseValue( ix, iy+1, iz + 1, it + i );
back[3] = GetNoiseValue( ix+1, iy+1, iz + 1, it + i );
fvalue = LERP( LERP( front[0], front[1], fx ), LERP( front[2], front[3], fx ), fy );
bvalue = LERP( LERP( back[0], back[1], fx ), LERP( back[2], back[3], fx ), fy );
value[i] = LERP( fvalue, bvalue, fz );
}
finalvalue = LERP( value[0], value[1], ft );
return finalvalue;
}
// used in the shader functions (GF_RANDOM) to implement a quasi random flickering.
#define VALR( a ) s_random[ ( a ) & ( NOISE_MASK )]
int R_RandomOn(float t)
{
return VALR((unsigned int) floor(t));
}