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cuberite-2a/source/cNoise.cpp
faketruth 386d58b586 MCServer c++ source files
git-svn-id: http://mc-server.googlecode.com/svn/trunk@3 0a769ca7-a7f5-676a-18bf-c427514a06d6
2011-10-03 18:41:19 +00:00

253 lines
11 KiB
C++

#include "cNoise.h"
#include <math.h>
#define FAST_FLOOR( x ) ( (x) < 0 ? ((int)x)-1 : ((int)x) )
cNoise::cNoise( unsigned int a_Seed )
: m_Seed( a_Seed )
{
}
cNoise::~cNoise()
{
}
/****************
* Random value generator
**/
float cNoise::IntNoise( int a_X ) const
{
int x = ((a_X*m_Seed)<<13) ^ a_X;
return ( 1.0f - ( (x * (x * x * 15731 + 789221) + 1376312589) & 0x7fffffff) / 1073741824.0f);
}
float cNoise::IntNoise2D( int a_X, int a_Y ) const
{
int n = a_X + a_Y * 57 + m_Seed*57*57;
n = (n<<13) ^ n;
return ( 1.0f - ( (n * (n * n * 15731 + 789221) + 1376312589) & 0x7fffffff) / 1073741824.0f);
}
float cNoise::IntNoise3D( int a_X, int a_Y, int a_Z ) const
{
int n = a_X + a_Y * 57 + a_Z * 57*57 + m_Seed*57*57*57;
n = (n<<13) ^ n;
return ( 1.0f - ( (n * (n * n * 15731 + 789221) + 1376312589) & 0x7fffffff) / 1073741824.0f);
}
/***************
* Interpolated (and 1 smoothed) noise in 1-dimension
**/
float cNoise::LinearNoise1D( float a_X ) const
{
int BaseX = FAST_FLOOR( a_X );
float FracX = (a_X) - BaseX;
return LinearInterpolate( IntNoise( BaseX ), IntNoise( BaseX+1 ), FracX);
}
float cNoise::CosineNoise1D( float a_X ) const
{
int BaseX = FAST_FLOOR( a_X );
float FracX = (a_X) - BaseX;
return CosineInterpolate( IntNoise( BaseX ), IntNoise( BaseX+1 ), FracX);
}
float cNoise::CubicNoise1D( float a_X ) const
{
int BaseX = FAST_FLOOR( a_X );
float FracX = (a_X) - BaseX;
return CubicInterpolate( IntNoise( BaseX-1 ), IntNoise( BaseX ), IntNoise( BaseX+1 ), IntNoise( BaseX+2 ), FracX);
}
float cNoise::SmoothNoise1D( int a_X ) const
{
return IntNoise(a_X)/2 + IntNoise(a_X-1)/4 + IntNoise(a_X+1)/4;
}
/******************
* Interpolated (and 1 smoothed) noise in 2-dimensions
**/
float cNoise::LinearNoise2D( float a_X, float a_Y ) const
{
const int BaseX = FAST_FLOOR( a_X );
const int BaseY = FAST_FLOOR( a_Y );
const float tl = IntNoise2D( BaseX, BaseY );
const float tr = IntNoise2D( BaseX+1, BaseY );
const float bl = IntNoise2D( BaseX, BaseY+1 );
const float br = IntNoise2D( BaseX+1, BaseY+1 );
const float FracX = (a_X) - BaseX;
const float interp1 = LinearInterpolate( tl, tr, FracX );
const float interp2 = LinearInterpolate( bl, br, FracX );
const float FracY = (a_Y) - BaseY;
return LinearInterpolate( interp1, interp2, FracY );
}
float cNoise::CosineNoise2D( float a_X, float a_Y ) const
{
const int BaseX = FAST_FLOOR( a_X );
const int BaseY = FAST_FLOOR( a_Y );
const float tl = IntNoise2D( BaseX, BaseY );
const float tr = IntNoise2D( BaseX+1, BaseY );
const float bl = IntNoise2D( BaseX, BaseY+1 );
const float br = IntNoise2D( BaseX+1, BaseY+1 );
const float FracX = (a_X) - BaseX;
const float interp1 = CosineInterpolate( tl, tr, FracX );
const float interp2 = CosineInterpolate( bl, br, FracX );
const float FracY = (a_Y) - BaseY;
return CosineInterpolate( interp1, interp2, FracY );
}
float cNoise::CubicNoise2D( float a_X, float a_Y ) const
{
const int BaseX = FAST_FLOOR( a_X );
const int BaseY = FAST_FLOOR( a_Y );
const float points[4][4] = {
IntNoise2D( BaseX-1, BaseY-1 ), IntNoise2D( BaseX, BaseY-1 ), IntNoise2D( BaseX+1, BaseY-1 ), IntNoise2D( BaseX+2, BaseY-1 ),
IntNoise2D( BaseX-1, BaseY ), IntNoise2D( BaseX, BaseY ), IntNoise2D( BaseX+1, BaseY ), IntNoise2D( BaseX+2, BaseY ),
IntNoise2D( BaseX-1, BaseY+1 ), IntNoise2D( BaseX, BaseY+1 ), IntNoise2D( BaseX+1, BaseY+1 ), IntNoise2D( BaseX+2, BaseY+1 ),
IntNoise2D( BaseX-1, BaseY+2 ), IntNoise2D( BaseX, BaseY+2 ), IntNoise2D( BaseX+1, BaseY+2 ), IntNoise2D( BaseX+2, BaseY+2 ),
};
const float FracX = (a_X) - BaseX;
const float interp1 = CubicInterpolate( points[0][0], points[0][1], points[0][2], points[0][3], FracX );
const float interp2 = CubicInterpolate( points[1][0], points[1][1], points[1][2], points[1][3], FracX );
const float interp3 = CubicInterpolate( points[2][0], points[2][1], points[2][2], points[2][3], FracX );
const float interp4 = CubicInterpolate( points[3][0], points[3][1], points[3][2], points[3][3], FracX );
const float FracY = (a_Y) - BaseY;
return CubicInterpolate( interp1, interp2, interp3, interp4, FracY );
}
/******************
* Interpolated (and 1 smoothed) noise in 3-dimensions
**/
float cNoise::CosineNoise3D( float a_X, float a_Y, float a_Z ) const
{
const int BaseX = FAST_FLOOR( a_X );
const int BaseY = FAST_FLOOR( a_Y );
const int BaseZ = FAST_FLOOR( a_Z );
const float ftl = IntNoise3D( BaseX, BaseY, BaseZ );
const float ftr = IntNoise3D( BaseX+1, BaseY, BaseZ );
const float fbl = IntNoise3D( BaseX, BaseY+1, BaseZ );
const float fbr = IntNoise3D( BaseX+1, BaseY+1, BaseZ );
const float btl = IntNoise3D( BaseX, BaseY, BaseZ+1 );
const float btr = IntNoise3D( BaseX+1, BaseY, BaseZ+1 );
const float bbl = IntNoise3D( BaseX, BaseY+1, BaseZ+1 );
const float bbr = IntNoise3D( BaseX+1, BaseY+1, BaseZ+1 );
const float FracX = (a_X) - BaseX;
const float finterp1 = CosineInterpolate( ftl, ftr, FracX );
const float finterp2 = CosineInterpolate( fbl, fbr, FracX );
const float binterp1 = CosineInterpolate( btl, btr, FracX );
const float binterp2 = CosineInterpolate( bbl, bbr, FracX );
const float FracY = (a_Y) - BaseY;
const float interp1 = CosineInterpolate( finterp1, finterp2, FracY );
const float interp2 = CosineInterpolate( binterp1, binterp2, FracY );
const float FracZ = (a_Z) - BaseZ;
return CosineInterpolate( interp1, interp2, FracZ );
}
float cNoise::CubicNoise3D( float a_X, float a_Y, float a_Z ) const
{
const int BaseX = FAST_FLOOR( a_X );
const int BaseY = FAST_FLOOR( a_Y );
const int BaseZ = FAST_FLOOR( a_Z );
const float points1[4][4] = {
IntNoise3D( BaseX-1, BaseY-1, BaseZ-1 ), IntNoise3D( BaseX, BaseY-1, BaseZ-1 ), IntNoise3D( BaseX+1, BaseY-1, BaseZ-1 ), IntNoise3D( BaseX+2, BaseY-1, BaseZ-1 ),
IntNoise3D( BaseX-1, BaseY, BaseZ-1 ), IntNoise3D( BaseX, BaseY, BaseZ-1 ), IntNoise3D( BaseX+1, BaseY, BaseZ-1 ), IntNoise3D( BaseX+2, BaseY, BaseZ-1 ),
IntNoise3D( BaseX-1, BaseY+1, BaseZ-1 ), IntNoise3D( BaseX, BaseY+1, BaseZ-1 ), IntNoise3D( BaseX+1, BaseY+1, BaseZ-1 ), IntNoise3D( BaseX+2, BaseY+1, BaseZ-1 ),
IntNoise3D( BaseX-1, BaseY+2, BaseZ-1 ), IntNoise3D( BaseX, BaseY+2, BaseZ-1 ), IntNoise3D( BaseX+1, BaseY+2, BaseZ-1 ), IntNoise3D( BaseX+2, BaseY+2, BaseZ-1 ),
};
const float FracX = (a_X) - BaseX;
const float x1interp1 = CubicInterpolate( points1[0][0], points1[0][1], points1[0][2], points1[0][3], FracX );
const float x1interp2 = CubicInterpolate( points1[1][0], points1[1][1], points1[1][2], points1[1][3], FracX );
const float x1interp3 = CubicInterpolate( points1[2][0], points1[2][1], points1[2][2], points1[2][3], FracX );
const float x1interp4 = CubicInterpolate( points1[3][0], points1[3][1], points1[3][2], points1[3][3], FracX );
const float points2[4][4] = {
IntNoise3D( BaseX-1, BaseY-1, BaseZ ), IntNoise3D( BaseX, BaseY-1, BaseZ ), IntNoise3D( BaseX+1, BaseY-1, BaseZ ), IntNoise3D( BaseX+2, BaseY-1, BaseZ ),
IntNoise3D( BaseX-1, BaseY, BaseZ ), IntNoise3D( BaseX, BaseY, BaseZ ), IntNoise3D( BaseX+1, BaseY, BaseZ ), IntNoise3D( BaseX+2, BaseY, BaseZ ),
IntNoise3D( BaseX-1, BaseY+1, BaseZ ), IntNoise3D( BaseX, BaseY+1, BaseZ ), IntNoise3D( BaseX+1, BaseY+1, BaseZ ), IntNoise3D( BaseX+2, BaseY+1, BaseZ ),
IntNoise3D( BaseX-1, BaseY+2, BaseZ ), IntNoise3D( BaseX, BaseY+2, BaseZ ), IntNoise3D( BaseX+1, BaseY+2, BaseZ ), IntNoise3D( BaseX+2, BaseY+2, BaseZ ),
};
const float x2interp1 = CubicInterpolate( points2[0][0], points2[0][1], points2[0][2], points2[0][3], FracX );
const float x2interp2 = CubicInterpolate( points2[1][0], points2[1][1], points2[1][2], points2[1][3], FracX );
const float x2interp3 = CubicInterpolate( points2[2][0], points2[2][1], points2[2][2], points2[2][3], FracX );
const float x2interp4 = CubicInterpolate( points2[3][0], points2[3][1], points2[3][2], points2[3][3], FracX );
const float points3[4][4] = {
IntNoise3D( BaseX-1, BaseY-1, BaseZ+1 ), IntNoise3D( BaseX, BaseY-1, BaseZ+1 ), IntNoise3D( BaseX+1, BaseY-1, BaseZ+1 ), IntNoise3D( BaseX+2, BaseY-1, BaseZ+1 ),
IntNoise3D( BaseX-1, BaseY, BaseZ+1 ), IntNoise3D( BaseX, BaseY, BaseZ+1 ), IntNoise3D( BaseX+1, BaseY, BaseZ+1 ), IntNoise3D( BaseX+2, BaseY, BaseZ+1 ),
IntNoise3D( BaseX-1, BaseY+1, BaseZ+1 ), IntNoise3D( BaseX, BaseY+1, BaseZ+1 ), IntNoise3D( BaseX+1, BaseY+1, BaseZ+1 ), IntNoise3D( BaseX+2, BaseY+1, BaseZ+1 ),
IntNoise3D( BaseX-1, BaseY+2, BaseZ+1 ), IntNoise3D( BaseX, BaseY+2, BaseZ+1 ), IntNoise3D( BaseX+1, BaseY+2, BaseZ+1 ), IntNoise3D( BaseX+2, BaseY+2, BaseZ+1 ),
};
const float x3interp1 = CubicInterpolate( points3[0][0], points3[0][1], points3[0][2], points3[0][3], FracX );
const float x3interp2 = CubicInterpolate( points3[1][0], points3[1][1], points3[1][2], points3[1][3], FracX );
const float x3interp3 = CubicInterpolate( points3[2][0], points3[2][1], points3[2][2], points3[2][3], FracX );
const float x3interp4 = CubicInterpolate( points3[3][0], points3[3][1], points3[3][2], points3[3][3], FracX );
const float points4[4][4] = {
IntNoise3D( BaseX-1, BaseY-1, BaseZ+2 ), IntNoise3D( BaseX, BaseY-1, BaseZ+2 ), IntNoise3D( BaseX+1, BaseY-1, BaseZ+2 ), IntNoise3D( BaseX+2, BaseY-1, BaseZ+2 ),
IntNoise3D( BaseX-1, BaseY, BaseZ+2 ), IntNoise3D( BaseX, BaseY, BaseZ+2 ), IntNoise3D( BaseX+1, BaseY, BaseZ+2 ), IntNoise3D( BaseX+2, BaseY, BaseZ+2 ),
IntNoise3D( BaseX-1, BaseY+1, BaseZ+2 ), IntNoise3D( BaseX, BaseY+1, BaseZ+2 ), IntNoise3D( BaseX+1, BaseY+1, BaseZ+2 ), IntNoise3D( BaseX+2, BaseY+1, BaseZ+2 ),
IntNoise3D( BaseX-1, BaseY+2, BaseZ+2 ), IntNoise3D( BaseX, BaseY+2, BaseZ+2 ), IntNoise3D( BaseX+1, BaseY+2, BaseZ+2 ), IntNoise3D( BaseX+2, BaseY+2, BaseZ+2 ),
};
const float x4interp1 = CubicInterpolate( points4[0][0], points4[0][1], points4[0][2], points4[0][3], FracX );
const float x4interp2 = CubicInterpolate( points4[1][0], points4[1][1], points4[1][2], points4[1][3], FracX );
const float x4interp3 = CubicInterpolate( points4[2][0], points4[2][1], points4[2][2], points4[2][3], FracX );
const float x4interp4 = CubicInterpolate( points4[3][0], points4[3][1], points4[3][2], points4[3][3], FracX );
const float FracY = (a_Y) - BaseY;
const float yinterp1 = CubicInterpolate( x1interp1, x1interp2, x1interp3, x1interp4, FracY );
const float yinterp2 = CubicInterpolate( x2interp1, x2interp2, x2interp3, x2interp4, FracY );
const float yinterp3 = CubicInterpolate( x3interp1, x3interp2, x3interp3, x3interp4, FracY );
const float yinterp4 = CubicInterpolate( x4interp1, x4interp2, x4interp3, x4interp4, FracY );
const float FracZ = (a_Z) - BaseZ;
return CubicInterpolate( yinterp1, yinterp2, yinterp3, yinterp4, FracZ );
}
/******************
* Private
**/
float cNoise::CubicInterpolate( float a_A, float a_B, float a_C, float a_D, float a_Pct ) const
{
float P = (a_D - a_C) - (a_A - a_B);
float Q = (a_A - a_B) - P;
float R = a_C - a_A;
float S = a_B;
return P*(a_Pct*a_Pct*a_Pct) + Q*(a_Pct*a_Pct) + R*a_Pct + S;
}
float cNoise::CosineInterpolate( float a_A, float a_B, float a_Pct ) const
{
const float ft = a_Pct * 3.1415927f;
const float f = (1.f - cosf(ft)) * 0.5f;
return a_A*(1-f) + a_B*f;
}
float cNoise::LinearInterpolate( float a_A, float a_B, float a_Pct ) const
{
return a_A*(1.f-a_Pct) + a_B*a_Pct;
}