So i made a simple demo!
It is very very simple!
The binary demo is http://xeus32.altervista.org/index.php? ... ar&mode=go
the Noise Class is :
Code: Select all
// Class automatically generated by Dev-C++ New Class wizard
#ifndef CPERLINNOISE_H
#define CPERLINNOISE_H
#include <irrlicht.h>
using namespace irr;
/**
* Perlin Noise
*/
class cPerlinNoise
{
public:
// class constructor
cPerlinNoise(core::dimension2d<s32> tDimension,float Frequency,float Persitence, float Octave,video::SColor MaskColor);
// class destructor
~cPerlinNoise();
/// Dimension
core::dimension2d<s32>* Dimension;
char* ImageBuffer;
float* FloatBuffer;
// interpola tra 2 punti
static float Interpolate1d(float x , float y , float a);
/**
* Genera Noise 2d
*/
static float Noise2d(int x, int y);
/**
* get value
**/
static float GetValue (float x , float y);
// Add noise
void Add(cPerlinNoise *in);
// interpolate between
void Interpolate(cPerlinNoise *in1 , cPerlinNoise *in2 ,float a);
};
#endif // CPERLINNOISE_H
Code: Select all
// Class automatically generated by Dev-C++ New Class wizard
#include "cperlinnoise.h" // class's header file
#include <stdlib.h>
// class constructor
cPerlinNoise::cPerlinNoise(core::dimension2d<s32> tDimension,float Frequency,float Persitence, float Octave,video::SColor MaskColor=video::SColor(255,255,255,255))
{
Dimension = new core::dimension2d<s32>(tDimension) ;
ImageBuffer = new char [Dimension->Height*Dimension->Width*4];
float freq = Frequency;
float pers = Persitence;
int random = rand();
for (int i=0; i<Dimension->Height; i++)
for (int j=0; j<Dimension->Width; j++)
{
float Total =0;
float Amplitude =1;
float freq_factor = freq;
for (int k =0 ; k < Octave; k++)
{
Total += GetValue((j+random)*freq_factor,(i+random)*freq_factor)*Amplitude;
Amplitude *= pers;
freq_factor *=2;
}
Total = Total *0.5f + 0.5f;
if (Total <0) Total =0;
if (Total >1) Total =1.0f;
int Offset = (i*Dimension->Width+j)*4;
// format ECF_A8R8G8B8
// ImageBuffer[Offset+3] alpha
// ImageBuffer[Offset+2] red
// ImageBuffer[Offset+1] green
// ImageBuffer[Offset+0] blue
ImageBuffer[Offset+0]= (int) (MaskColor.getBlue() * Total); //blue
ImageBuffer[Offset+1]= (int) (MaskColor.getGreen() * Total); //green
ImageBuffer[Offset+2]= (int) (MaskColor.getRed() * Total); //red
ImageBuffer[Offset+3]= (int) (MaskColor.getAlpha() * Total); //alpha
}
}
// class destructor
cPerlinNoise::~cPerlinNoise()
{
delete ImageBuffer;
}
/*
* Genera Noise 2d
*/
float cPerlinNoise::Noise2d(int x, int y)
{
int n = x +y *57;
n= (n<<13)*n;
float res = (float) (1.0f - ((n*(n*n*15731+789221)+ 1376312589)&0x7FFFFFFF) / 1073741824.0);
return res;
}
/**
* interpola tra 2 punti
**/
float cPerlinNoise::Interpolate1d(float x , float y , float a)
{
float invA = 1-a;
float fac1 = 3* (invA)*(invA)-2*(invA)*(invA)*(invA);
float fac2 = 3* (a)*(a)-2*(a)*(a)*(a);
return fac1* x + fac2* y;
}
// get value
float cPerlinNoise::GetValue (float x , float y)
{
int Xint = (int)x;
int Yint = (int)y;
float Xfrac = x - Xint;
float Yfrac = y - Yint;
float x0y0 = Noise2d(Xint,Yint);
float x1y0 = Noise2d(Xint+1,Yint);
float x0y1 = Noise2d(Xint,Yint+1);
float x1y1 = Noise2d(Xint+1,Yint+1);
float v1 = Interpolate1d(x0y0,x1y0,Xfrac);
float v2 = Interpolate1d(x0y1,x1y1,Xfrac);
float fin = Interpolate1d(v1,v2,Yfrac);
return fin;
}
// Add noise
void cPerlinNoise::Add(cPerlinNoise *in)
{
if ( in->Dimension != Dimension)
return;
for (int i=0; i<Dimension->Height; i++)
for (int j=0; j<Dimension->Width; j++)
{
int Offset = (i*Dimension->Width+j)*4;
int color = in->ImageBuffer[Offset] + ImageBuffer[Offset];
if ( color < 0) color = 0;
if ( color > 255) color = 255;
ImageBuffer[Offset] = color;
color = in->ImageBuffer[Offset+1] + ImageBuffer[Offset+1];
if ( color < 0) color = 0;
if ( color > 255) color = 255;
ImageBuffer[Offset+1] = color;
color = in->ImageBuffer[Offset+2] + ImageBuffer[Offset+2];
if ( color < 0) color = 0;
if ( color > 255) color = 255;
ImageBuffer[Offset+2] = color;
color = in->ImageBuffer[Offset+3] + ImageBuffer[Offset+3];
if ( color < 0) color = 0;
if ( color > 255) color = 255;
ImageBuffer[Offset+3] = color;
}
}
// interpolate between
void cPerlinNoise::Interpolate(cPerlinNoise *in1 , cPerlinNoise *in2 ,float a)
{
if (a>1) a=1;
if (a<0) a=0;
float InvA= 1-a;
for (int i=0; i<Dimension->Height; i++)
for (int j=0; j<Dimension->Width; j++)
{
int Offset = (i*Dimension->Width+j)*4;
int color = in1->ImageBuffer[Offset]*a + in2->ImageBuffer[Offset]*InvA;
if ( color < 0) color = 0;
if ( color > 255) color = 255;
ImageBuffer[Offset] = color;
color = in1->ImageBuffer[Offset+1]*a + in2->ImageBuffer[Offset+1]*InvA;
if ( color < 0) color = 0;
if ( color > 255) color = 255;
ImageBuffer[Offset+1] = color;
color = in1->ImageBuffer[Offset+2]*a + in2->ImageBuffer[Offset+2]*InvA;
if ( color < 0) color = 0;
if ( color > 255) color = 255;
ImageBuffer[Offset+2] = color;
color = in1->ImageBuffer[Offset+3]*a + in2->ImageBuffer[Offset+3]*InvA;
if ( color < 0) color = 0;
if ( color > 255) color = 255;
ImageBuffer[Offset+3] = color;
}
}
