99 lines
2.5 KiB
C++
99 lines
2.5 KiB
C++
// Copyright (C) 2017 Rémi Bèges
|
|
// This file is part of the "Nazara Engine - Noise module"
|
|
// For conditions of distribution and use, see copyright notice in Config.hpp
|
|
|
|
#include <Nazara/Noise/HybridMultiFractal.hpp>
|
|
#include <Nazara/Noise/Debug.hpp>
|
|
|
|
namespace Nz
|
|
{
|
|
HybridMultiFractal::HybridMultiFractal(const NoiseBase & source) :
|
|
m_source(source)
|
|
{
|
|
}
|
|
|
|
float HybridMultiFractal::Get(float x, float y, float scale) const
|
|
{
|
|
float offset = 1.0f;
|
|
float value = (m_source.Get(x, y, scale) + offset) * m_exponent_array.at(0);
|
|
float weight = value;
|
|
float signal = 0.f;
|
|
|
|
scale *= m_lacunarity;
|
|
|
|
for(int i(1) ; i < m_octaves; ++i)
|
|
{
|
|
if (weight > 1.f)
|
|
weight = 1.f;
|
|
|
|
signal = (m_source.Get(x, y, scale) + offset) * m_exponent_array.at(i);
|
|
value += weight * signal;
|
|
weight *= signal;
|
|
scale *= m_lacunarity;
|
|
}
|
|
|
|
float remainder = m_octaves - static_cast<int>(m_octaves);
|
|
|
|
if (remainder > 0.f)
|
|
value += remainder * m_source.Get(x, y, scale) * m_exponent_array.at(static_cast<int>(m_octaves-1));
|
|
|
|
return value / m_sum - offset;
|
|
}
|
|
|
|
float HybridMultiFractal::Get(float x, float y, float z, float scale) const
|
|
{
|
|
float offset = 1.0f;
|
|
float value = (m_source.Get(x, y, z, scale) + offset) * m_exponent_array.at(0);
|
|
float weight = value;
|
|
float signal = 0.f;
|
|
|
|
scale *= m_lacunarity;
|
|
|
|
for(int i(1) ; i < m_octaves; ++i)
|
|
{
|
|
if (weight > 1.f)
|
|
weight = 1.f;
|
|
|
|
signal = (m_source.Get(x, y, z, scale) + offset) * m_exponent_array.at(i);
|
|
value += weight * signal;
|
|
weight *= signal;
|
|
scale *= m_lacunarity;
|
|
}
|
|
|
|
float remainder = m_octaves - static_cast<int>(m_octaves);
|
|
|
|
if (remainder > 0.f)
|
|
value += remainder * m_source.Get(x, y, z, scale) * m_exponent_array.at(static_cast<int>(m_octaves-1));
|
|
|
|
return value / m_sum - offset;
|
|
}
|
|
|
|
float HybridMultiFractal::Get(float x, float y, float z, float w, float scale) const
|
|
{
|
|
float offset = 1.0f;
|
|
float value = (m_source.Get(x, y, z, w, scale) + offset) * m_exponent_array.at(0);
|
|
float weight = value;
|
|
float signal = 0.f;
|
|
|
|
scale *= m_lacunarity;
|
|
|
|
for(int i(1) ; i < m_octaves; ++i)
|
|
{
|
|
if (weight > 1.f)
|
|
weight = 1.f;
|
|
|
|
signal = (m_source.Get(x, y, z, w, scale) + offset) * m_exponent_array.at(i);
|
|
value += weight * signal;
|
|
weight *= signal;
|
|
scale *= m_lacunarity;
|
|
}
|
|
|
|
float remainder = m_octaves - static_cast<int>(m_octaves);
|
|
|
|
if (remainder > 0.f)
|
|
value += remainder * m_source.Get(x, y, z, w, scale) * m_exponent_array.at(static_cast<int>(m_octaves-1));
|
|
|
|
return value / m_sum - offset;
|
|
}
|
|
}
|