FactoryCraft-Server/FactoryCraft/NoiseInterpolator.cpp

#include "NoiseInterpolator.h"
#include "Text.h"

using namespace Framework;

NoiseInterpolator::NoiseInterpolator( int seed, std::function<Noise* (int)> noiseSupplier, int width, int height )
    : Noise(),
    noiseSize( width, height ),
    cache( 10, []( int k ) {return k; }, CacheCleanupStrategy::LONGEST_NOT_USED ),
    noiseSupplier( noiseSupplier ),
    seed( seed )
{}

double NoiseInterpolator::getRealNoise( double x, double y, double z )
{
    int ix = (int)ceil( x ), iy = (int)ceil( y );
    int xOff = ix % noiseSize.x, yOff = iy % noiseSize.y;
    int xI = ix / noiseSize.x, yI = iy / noiseSize.y;
    if( ix < 0 )
        xI--;
    if( iy < 0 )
        yI--;
    int key = ((xI & 0xFFFF) << 16) | (yI & 0xFFFF);
    if( !cache.has( key ) )
        cache.put( key, RCPointer<Noise>::of( noiseSupplier( key + seed ) ) );
    return cache.get( key )->getNoise( (xOff + 1 - (ix - x)), (yOff + 1 - (iy - y)), z );
}

double NoiseInterpolator::getNoise( double x, double y, double z )
{
    const double weights[ 6 ] = { 0.32, 0.17, 0.09, 0.05, 0.03, 0.02 };
    double sum = 0;
    for( int xi = -5; xi <= 5; xi++ )
    {
        for( int yi = -5; yi <= 5; yi++ )
            sum += getRealNoise( x + xi, y + yi, z ) * weights[ abs( xi ) ] * weights[ abs( yi ) ];
    }
    return sum;
}

int NoiseInterpolator::getSeed() const
{
    return seed;
}