csgo-2018-source/mathlib/ssenoise.cpp
2021-07-24 21:11:47 -07:00

236 lines
10 KiB
C++

//========= Copyright © 1996-2006, Valve Corporation, All rights reserved. ============//
//
// Purpose: Fast low quality noise suitable for real time use
//
//=====================================================================================//
#include <math.h>
#include <float.h> // needed for flt_epsilon
#include "basetypes.h"
#include "tier0/dbg.h"
#include "mathlib/mathlib.h"
#include "mathlib/vector.h"
#include "mathlib/ssemath.h"
// memdbgon must be the last include file in a .cpp file!!!
#include "tier0/memdbgon.h"
#include "noisedata.h"
#define MAGIC_NUMBER (1<<15) // gives 8 bits of fraction
static fltx4 Four_MagicNumbers = { MAGIC_NUMBER, MAGIC_NUMBER, MAGIC_NUMBER, MAGIC_NUMBER };
static ALIGN16 int32 idx_mask[4]= {0xffff, 0xffff, 0xffff, 0xffff};
#define MASK255 (*((fltx4 *)(& idx_mask )))
// returns 0..1
static inline float GetLatticePointValue( int idx_x, int idx_y, int idx_z )
{
int ret_idx = perm_a[idx_x & 0xff];
ret_idx = perm_b[( idx_y + ret_idx ) & 0xff];
ret_idx = perm_c[( idx_z + ret_idx ) & 0xff];
return impulse_xcoords[ret_idx];
}
fltx4 NoiseSIMD( const fltx4 & x, const fltx4 & y, const fltx4 & z )
{
// use magic to convert to integer index
fltx4 x_idx = AndSIMD( MASK255, AddSIMD( x, Four_MagicNumbers ) );
fltx4 y_idx = AndSIMD( MASK255, AddSIMD( y, Four_MagicNumbers ) );
fltx4 z_idx = AndSIMD( MASK255, AddSIMD( z, Four_MagicNumbers ) );
fltx4 lattice000 = Four_Zeros, lattice001 = Four_Zeros, lattice010 = Four_Zeros, lattice011 = Four_Zeros;
fltx4 lattice100 = Four_Zeros, lattice101 = Four_Zeros, lattice110 = Four_Zeros, lattice111 = Four_Zeros;
// FIXME: Converting the input vectors to int indices will cause load-hit-stores (48 bytes)
// Converting the indexed noise values back to vectors will cause more (128 bytes)
// The noise table could store vectors if we chunked it into 2x2x2 blocks.
fltx4 xfrac = Four_Zeros, yfrac = Four_Zeros, zfrac = Four_Zeros;
#define DOPASS(i) \
{ unsigned int xi = SubInt( x_idx, i ); \
unsigned int yi = SubInt( y_idx, i ); \
unsigned int zi = SubInt( z_idx, i ); \
SubFloat( xfrac, i ) = (xi & 0xff)*(1.0/256.0); \
SubFloat( yfrac, i ) = (yi & 0xff)*(1.0/256.0); \
SubFloat( zfrac, i ) = (zi & 0xff)*(1.0/256.0); \
xi>>=8; \
yi>>=8; \
zi>>=8; \
\
SubFloat( lattice000, i ) = GetLatticePointValue( xi,yi,zi ); \
SubFloat( lattice001, i ) = GetLatticePointValue( xi,yi,zi+1 ); \
SubFloat( lattice010, i ) = GetLatticePointValue( xi,yi+1,zi ); \
SubFloat( lattice011, i ) = GetLatticePointValue( xi,yi+1,zi+1 ); \
SubFloat( lattice100, i ) = GetLatticePointValue( xi+1,yi,zi ); \
SubFloat( lattice101, i ) = GetLatticePointValue( xi+1,yi,zi+1 ); \
SubFloat( lattice110, i ) = GetLatticePointValue( xi+1,yi+1,zi ); \
SubFloat( lattice111, i ) = GetLatticePointValue( xi+1,yi+1,zi+1 ); \
}
DOPASS( 0 );
DOPASS( 1 );
DOPASS( 2 );
DOPASS( 3 );
// now, we have 8 lattice values for each of four points as m128s, and interpolant values for
// each axis in m128 form in [xyz]frac. Perfom the trilinear interpolation as SIMD ops
// first, do x interpolation
fltx4 l2d00 = AddSIMD( lattice000, MulSIMD( xfrac, SubSIMD( lattice100, lattice000 ) ) );
fltx4 l2d01 = AddSIMD( lattice001, MulSIMD( xfrac, SubSIMD( lattice101, lattice001 ) ) );
fltx4 l2d10 = AddSIMD( lattice010, MulSIMD( xfrac, SubSIMD( lattice110, lattice010 ) ) );
fltx4 l2d11 = AddSIMD( lattice011, MulSIMD( xfrac, SubSIMD( lattice111, lattice011 ) ) );
// now, do y interpolation
fltx4 l1d0 = AddSIMD( l2d00, MulSIMD( yfrac, SubSIMD( l2d10, l2d00 ) ) );
fltx4 l1d1 = AddSIMD( l2d01, MulSIMD( yfrac, SubSIMD( l2d11, l2d01 ) ) );
// final z interpolation
fltx4 rslt = AddSIMD( l1d0, MulSIMD( zfrac, SubSIMD( l1d1, l1d0 ) ) );
// map to 0..1
return MulSIMD( Four_Twos, SubSIMD( rslt, Four_PointFives ) );
}
static inline void GetVectorLatticePointValue( int idx, fltx4 &x, fltx4 &y, fltx4 &z,
int idx_x, int idx_y, int idx_z )
{
int ret_idx = perm_a[idx_x & 0xff];
ret_idx = perm_b[( idx_y + ret_idx ) & 0xff];
ret_idx = perm_c[( idx_z + ret_idx ) & 0xff];
float const *pData = s_randomGradients + ret_idx * 3;
SubFloat( x, idx ) = pData[0];
SubFloat( y, idx ) = pData[1];
SubFloat( z, idx ) = pData[2];
}
FourVectors DNoiseSIMD( const fltx4 & x, const fltx4 & y, const fltx4 & z )
{
// use magic to convert to integer index
fltx4 x_idx = AndSIMD( MASK255, AddSIMD( x, Four_MagicNumbers ) );
fltx4 y_idx = AndSIMD( MASK255, AddSIMD( y, Four_MagicNumbers ) );
fltx4 z_idx = AndSIMD( MASK255, AddSIMD( z, Four_MagicNumbers ) );
fltx4 xlattice000 = Four_Zeros, xlattice001 = Four_Zeros, xlattice010 = Four_Zeros, xlattice011 = Four_Zeros;
fltx4 xlattice100 = Four_Zeros, xlattice101 = Four_Zeros, xlattice110 = Four_Zeros, xlattice111 = Four_Zeros;
fltx4 ylattice000 = Four_Zeros, ylattice001 = Four_Zeros, ylattice010 = Four_Zeros, ylattice011 = Four_Zeros;
fltx4 ylattice100 = Four_Zeros, ylattice101 = Four_Zeros, ylattice110 = Four_Zeros, ylattice111 = Four_Zeros;
fltx4 zlattice000 = Four_Zeros, zlattice001 = Four_Zeros, zlattice010 = Four_Zeros, zlattice011 = Four_Zeros;
fltx4 zlattice100 = Four_Zeros, zlattice101 = Four_Zeros, zlattice110 = Four_Zeros, zlattice111 = Four_Zeros;
// FIXME: Converting the input vectors to int indices will cause load-hit-stores (48 bytes)
// Converting the indexed noise values back to vectors will cause more (128 bytes)
// The noise table could store vectors if we chunked it into 2x2x2 blocks.
fltx4 xfrac = Four_Zeros, yfrac = Four_Zeros, zfrac = Four_Zeros;
#define DODPASS(i) \
{ unsigned int xi = SubInt( x_idx, i ); \
unsigned int yi = SubInt( y_idx, i ); \
unsigned int zi = SubInt( z_idx, i ); \
SubFloat( xfrac, i ) = (xi & 0xff)*(1.0/256.0); \
SubFloat( yfrac, i ) = (yi & 0xff)*(1.0/256.0); \
SubFloat( zfrac, i ) = (zi & 0xff)*(1.0/256.0); \
xi>>=8; \
yi>>=8; \
zi>>=8; \
\
GetVectorLatticePointValue( i, xlattice000, ylattice000, zlattice000, xi,yi,zi ); \
GetVectorLatticePointValue( i, xlattice001, ylattice001, zlattice001, xi,yi,zi+1 ); \
GetVectorLatticePointValue( i, xlattice010, ylattice010, zlattice010, xi,yi+1,zi ); \
GetVectorLatticePointValue( i, xlattice011, ylattice011, zlattice011, xi,yi+1,zi+1 ); \
GetVectorLatticePointValue( i, xlattice100, ylattice100, zlattice100, xi+1,yi,zi ); \
GetVectorLatticePointValue( i, xlattice101, ylattice101, zlattice101, xi+1,yi,zi+1 ); \
GetVectorLatticePointValue( i, xlattice110, ylattice110, zlattice110, xi+1,yi+1,zi ); \
GetVectorLatticePointValue( i, xlattice111, ylattice111, zlattice111, xi+1,yi+1,zi+1 ); \
}
DODPASS( 0 );
DODPASS( 1 );
DODPASS( 2 );
DODPASS( 3 );
// now, we have 8 lattice values for each of four points as m128s, and interpolant values for
// each axis in m128 form in [xyz]frac. Perfom the trilinear interpolation as SIMD ops
// first, do x interpolation
fltx4 xl2d00 = AddSIMD( xlattice000, MulSIMD( xfrac, SubSIMD( xlattice100, xlattice000 ) ) );
fltx4 xl2d01 = AddSIMD( xlattice001, MulSIMD( xfrac, SubSIMD( xlattice101, xlattice001 ) ) );
fltx4 xl2d10 = AddSIMD( xlattice010, MulSIMD( xfrac, SubSIMD( xlattice110, xlattice010 ) ) );
fltx4 xl2d11 = AddSIMD( xlattice011, MulSIMD( xfrac, SubSIMD( xlattice111, xlattice011 ) ) );
// now, do y interpolation
fltx4 xl1d0 = AddSIMD( xl2d00, MulSIMD( yfrac, SubSIMD( xl2d10, xl2d00 ) ) );
fltx4 xl1d1 = AddSIMD( xl2d01, MulSIMD( yfrac, SubSIMD( xl2d11, xl2d01 ) ) );
// final z interpolation
FourVectors rslt;
rslt.x = AddSIMD( xl1d0, MulSIMD( zfrac, SubSIMD( xl1d1, xl1d0 ) ) );
fltx4 yl2d00 = AddSIMD( ylattice000, MulSIMD( xfrac, SubSIMD( ylattice100, ylattice000 ) ) );
fltx4 yl2d01 = AddSIMD( ylattice001, MulSIMD( xfrac, SubSIMD( ylattice101, ylattice001 ) ) );
fltx4 yl2d10 = AddSIMD( ylattice010, MulSIMD( xfrac, SubSIMD( ylattice110, ylattice010 ) ) );
fltx4 yl2d11 = AddSIMD( ylattice011, MulSIMD( xfrac, SubSIMD( ylattice111, ylattice011 ) ) );
// now, do y interpolation
fltx4 yl1d0 = AddSIMD( yl2d00, MulSIMD( yfrac, SubSIMD( yl2d10, yl2d00 ) ) );
fltx4 yl1d1 = AddSIMD( yl2d01, MulSIMD( yfrac, SubSIMD( yl2d11, yl2d01 ) ) );
// final z interpolation
rslt.y = AddSIMD( yl1d0, MulSIMD( zfrac, SubSIMD( yl1d1, yl1d0 ) ) );
fltx4 zl2d00 = AddSIMD( zlattice000, MulSIMD( xfrac, SubSIMD( zlattice100, zlattice000 ) ) );
fltx4 zl2d01 = AddSIMD( zlattice001, MulSIMD( xfrac, SubSIMD( zlattice101, zlattice001 ) ) );
fltx4 zl2d10 = AddSIMD( zlattice010, MulSIMD( xfrac, SubSIMD( zlattice110, zlattice010 ) ) );
fltx4 zl2d11 = AddSIMD( zlattice011, MulSIMD( xfrac, SubSIMD( zlattice111, zlattice011 ) ) );
// now, do y interpolation
fltx4 zl1d0 = AddSIMD( zl2d00, MulSIMD( yfrac, SubSIMD( zl2d10, zl2d00 ) ) );
fltx4 zl1d1 = AddSIMD( zl2d01, MulSIMD( yfrac, SubSIMD( zl2d11, zl2d01 ) ) );
// final z interpolation
rslt.z = AddSIMD( zl1d0, MulSIMD( zfrac, SubSIMD( zl1d1, zl1d0 ) ) );
return rslt;
}
fltx4 NoiseSIMD( FourVectors const &pos )
{
return NoiseSIMD( pos.x, pos.y, pos.z );
}
FourVectors DNoiseSIMD( FourVectors const &pos )
{
return DNoiseSIMD( pos.x, pos.y, pos.z );
}
FourVectors CurlNoiseSIMD( FourVectors const &pos )
{
FourVectors fl4Comp1 = DNoiseSIMD( pos );
FourVectors fl4Pos = pos;
fl4Pos.x = AddSIMD( fl4Pos.x, ReplicateX4( 43.256 ) );
fl4Pos.y = AddSIMD( fl4Pos.y, ReplicateX4( -67.89 ) );
fl4Pos.z = AddSIMD( fl4Pos.z, ReplicateX4( 1338.2 ) );
FourVectors fl4Comp2 = DNoiseSIMD( fl4Pos );
fl4Pos.x = AddSIMD( fl4Pos.x, ReplicateX4( -129.856 ) );
fl4Pos.y = AddSIMD( fl4Pos.y, ReplicateX4( -967.23 ) );
fl4Pos.z = AddSIMD( fl4Pos.z, ReplicateX4( 2338.98 ) );
FourVectors fl4Comp3 = DNoiseSIMD( fl4Pos );
// now we have the 3 derivatives of a vector valued field. return the curl of the field.
FourVectors fl4Ret;
fl4Ret.x = SubSIMD( fl4Comp3.y, fl4Comp2.z );
fl4Ret.y = SubSIMD( fl4Comp1.z, fl4Comp3.x );
fl4Ret.z = SubSIMD( fl4Comp2.x, fl4Comp1.y );
return fl4Ret;
}