// Copyright (C) 2015 Rémi Bèges
// This file is part of the "Nazara Engine".
// For conditions of distribution and use, see copyright notice in Config.hpp

#include <Nazara/Core/Error.hpp>
#include <Nazara/Noise/Config.hpp>
#include <Nazara/Noise/FBM2D.hpp>
#include <Nazara/Noise/Perlin2D.hpp>
#include <Nazara/Noise/Simplex2D.hpp>
#include <Nazara/Noise/Debug.hpp>

namespace Nz
{
	FBM2D::FBM2D(NoiseType source, unsigned int seed)
	{
		switch(source)
		{
			case PERLIN:
				m_source = new Perlin2D();
			break;

			default:
				m_source = new Simplex2D();
			break;
		}
		m_source->SetNewSeed(seed);
		m_source->ShufflePermutationTable();
		m_noiseType = source;
	}

	float FBM2D::GetValue(float x, float y, float resolution)
	{
		this->RecomputeExponentArray();

		m_value = 0.0;

		for (int i(0); i < m_octaves; ++i)
		{
			m_value += m_source->GetValue(x,y,resolution) * m_exponent_array[i];
			resolution *= m_lacunarity;
		}
		m_remainder = m_octaves - static_cast<int>(m_octaves);

		if(!NumberEquals(m_remainder, static_cast<float>(0.0)))
		  m_value += m_remainder * m_source->GetValue(x,y,resolution) * m_exponent_array[static_cast<int>(m_octaves-1)];

		return m_value/this->m_sum;
	}

	FBM2D::~FBM2D()
	{
		delete m_source;
	}
}
