/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Copyright 2012-2015 Danny Robson <danny@nerdcruft.net>
 */

#ifndef __UTIL_NOISE_FRACTAL_HMF_HPP
#define __UTIL_NOISE_FRACTAL_HMF_HPP

#include <cstdint>

#include "../../point.hpp"

namespace util { namespace noise { namespace fractal {
    ///////////////////////////////////////////////////////////////////////
    /// Musgrave's "Hybrid MultiFractal"
    template <class B>
    struct hmf : public base<B> {
        using value_t = typename base<B>::value_t;
        using point_t = typename base<B>::point_t;

        // H should be fairly low due to the decreasing weight parameter in eval
        static constexpr unsigned DEFAULT_OCTAVES = 6;
        static constexpr value_t DEFAULT_H = value_t(0.25);
        static constexpr value_t DEFAULT_FREQUENCY = value_t(0.1);
        static constexpr value_t DEFAULT_LACUNARITY = 2;
        static constexpr value_t DEFAULT_AMPLITUDE = 1;
        static constexpr value_t DEFAULT_GAIN = 1 / DEFAULT_LACUNARITY;
        static constexpr value_t DEFAULT_OFFSET = value_t(0.7);

        hmf (seed_t,
             unsigned octaves,
             value_t H,
             value_t frequency,
             value_t lacunarity,
             value_t amplitude,
             value_t gain,
             value_t offset);

        explicit hmf (seed_t = 0);

        value_t operator() (point_t) const;

    private:
        value_t m_offset;
    };
} } }

#include "hmf.ipp"

#endif